Antenatal care | Flashcards
(228 cards)
1
Q
What is the definition of gestation age?
A
Duration of pregnancy dated from the first day of the last menstrual period (LMP)
2
Q
How many weeks gestation is the baby considered an:
- Embryo
- Fetus
A
- Embryo = fertilisation to 10 weeks gestation
2. Fetus = 10 weeks gestation to birth
3
Q
Currently what is the median age of women giving birth in developed countries?
A
30 years
4
Q
Why are the rates of pregnancy in the over 35 and 40 age group continue to rise (4)?
A
- Assess to assisted reproductive technologies has increased
- Social factors e.g. work
- Economic factors
- Education factors
5
Q
What are the dates for the 3 trimesters of pregnancy?
A
Trimester 1 = week 0-13
Trimester 2 = week 14-27
Trimester 3 = week 28 onwards
6
Q
How many weeks are:
- Full term
- Preterm
- Viability
A
- Full term = 37 weeks
- Preterm = <36 weeks
- Viability = >24 weeks
7
Q
At how many weeks do women usually deliver?
A
38-42 weeks
8
Q
What needs to be asked about concerning past obstetric history (10)?
A
- Gravidity - no. times a woman has been pregnant irrespective of outcome of pregnancy
- Any spontaneous miscarriages and induced abortions
- Complications during previous pregnancies
- Details of induction of labour
- Gestation at delivery
- Presentation and method of birth, assisted?
- Complications in the puerperium e.g. postpartum haemorrhage
- Birthweight of the baby, neonatal complications (need for special care baby unit) and long-term outcome
- Maternal physical and mental health during and after each pregnancy
- Breastfeeding history
9
Q
Once a pregnancy has been confirmed, what should the doctor ask about in the history regarding complications or possible poor outcome of current pregnancy (8)?
A
.1. Whether pregnancy is wanted
- Symptoms of pregnancy or problems e.g. N+V/bleeding/pain
- Maternal and family history of hypertension, diabetes, mental health disorders and congenital and familial disorders
- Pre-pregnancy body weight, recent and past history of weight loss/gain and eating behaviour
- Cigarette smoking, caffeine intake, alcohol and other prescribed/social drug use
- Current and past history of physical and sexual abuse
- Family and community support
- Whether the woman has any concerns or worries about pregnancy.
10
Q
Define gravidity
A
No. times a woman has been pregnant, irrespective of the outcome of the pregnancy e.g. termination/miscarriage, ectopic pregnancy
11
Q
- What is primigravida?
2. What is multigravida?
A
- Pregnant for the first time
2. Pregnant on 2 or more occasions
12
Q
What is parity?
A
Describes number of live-born children and stillbirths a woman has delivered after 24 weeks or with a birthweight of 500g
13
Q
What are the 2 ways of calculating gestational age and pregnancy due date?
A
- Using LMP
2. Using ultrasound
14
Q
How do you calculate the pregnancy due date using LMP?
A
- Ask the woman if the length of her menstrual cycle falls into the normal range (22-35 days)
- Add 1 year and 10 days to the first day of her LMP, then subtract 3 months
15
Q
If a woman’s LMP began on 14th November 2010, what is her due date?
A
24th August 2011 (+/- 14 days)
16
Q
How do you calculate gestational age?
A
Calculated from the first day of the mothers LMP
17
Q
What 4 areas should be addressed regarding preconceptual care?
A
- Immunisation
- Dietary and vitamin supplementation
- Medications
- Advice on diet and exercise
18
Q
In preconceptual care, what are women assessed for regarding immunisations?
A
The need for rubella, varicella and pertussis immunisation
19
Q
What cautions need to be taken when giving immunisations to a woman who wants to get pregnant?
A
Vaccines for rubella, varicella and pertussis are live attenuated viral vaccines so the woman should defer contraception for 28 days after administration
20
Q
What dietary and vitamin supplementation should a woman take preconceptually (3)?
A
- Folic acid supplement (400ug daily) for at least 1 month prior to conception and first 3 months of pregnancy
- Certain risk groups should take a higher dose (5mg daily) such as those on anti-epileptic agents, obese women, diabetic women or women with a past history of neural tube defects
- Iodine supplements is also recommended in countries where there is a dietary deficiency to aid in the development of the fetal brain
21
Q
What is done regarding medications during preconceptual care?
A
It is reviewed and optimised
22
Q
What should be considered when enquiring about family history in a woman who wants to get or is pregnant (2)?
A
- Most women will be aware of any significant family history of the common genetically based diseases
- They can be offered pre-natal diagnosis testing for women who would consider a termination of affected pregnancy when they are known to be a carrier of a recessively inherited genetic disorder and the father of the baby is known to be a carrier of the same disorder, or carrier status of the father is unknown and cannot be established
23
Q
How do dominantly-inherited disorders translate clinically i.e. how likely is a child going to get the disease?
A
Only one parent needs to carry the mutation for the condition to be passed onto the child (50% chance)
24
Q
What are 4 examples of genetic diseases that show a dominant-inheritance?
(nice to know)
A
- Neurofibromatosis - mutation in NF1 gene causing benign tumours to grow along nerves
- Tuberous sclerosis - mutation in TSC1 or 2 genes leading to benign tumours to grow in various parts of the body
- Huntington’s disease - mutation in HTT gene, causing progressive brain disorder with uncontrolled movements, emotional problems and loss of cognitive abilities
- Adult polycystic disease - Mutation in PKD1 or 2, causes cysts to develop in kidneys, affecting its function
25
How do recessively-inherited disorders translate clinically i.e. how likely is a child going to get the disease?
Condition is passed on if both parents have a copy of the faulty gene I.e. are carriers of the condition. If the child inherits one copy of the faulty gene, they are a carrier of the condition but won't have it.
26
What are 2 common recessively-inherited disorders?
1. Cystic fibrosis
| 2. Haemoglobinopathies e.g. sickle cell anaemia
27
What is the pathophysiology of CF? (2)
1. Caused by mutation in CFTR gene which usually codes for Cl- channels. Cl- controls movement of water in tissues, necessary for the production of thin, freely-flowing mucus.
2. Mutations lead to thick and sticky mucus that damages respiratory and digestive systems
28
What are the clinical features of CF? (6)
1. Chronic coughing
2. Wheezing
3. Inflammation
4. Mucus build up, leading to infection, which result in permanent lung damage and scarring
5. Poor growth or weight gain
6. Frequent greasy, bulky stools or difficulty with bowel movements
29
What is the pathophysiology of sickle cell anaemia?
Patients have inherited the abnormal gene Hb S which forms an abnormal beta-globin chain that causes it to polymerize when deoxygenated, which distorts the erythrocyte into a sickle shape.
30
How do X-linked disorders translate clinically i.e. how likely is a child going to get the disease?
Mutation on the X chromosome. Don't affect females to a significant degree as they have 2 X chromosomes. Males can't inherit X-linked mutations from their fathers because they receive a Y chromosome from them, so only gets the condition if he inherits from his mother. He cannot compensate as he only has 1 X chromosome
31
What are 3 examples of X-linked disorders?
| nice to know
1. Duchenne's muscular dystrophy - mutation of the dystrophin gene at Xp21, causing worsening muscle weakness from the age of 4
2. Fragile X syndrome - mutations in FMR1 gene causing developmental problems
3. Haemophilia A and B - Reduced levels of factor VIII and IX respectively, causing abnormal clotting, leading to prolonged bleeding
32
Why is it difficult to assess the effects of substance use in pregnancy?
Illicit substance use is associated with drinking, and malnutrition as well
33
What are the 4 most common illicit substances taken during pregnancy?
1. Heroin
2. Cocaine
3. Amphetamines
4. Marijuana
34
What are the dangers of heroin use during pregnancy (4)?
Associated with increased risk of:
1. IUGR
2. Perinatal death
3. Preterm labour
4. 50% of infants will also suffer from neonatal withdrawal.
35
What are the dangers of amphetamine use during pregnancy (6)?
Associated with increased risk of:
1. Miscarriage
2. Preterm birth
3. Growth restriction
4. Placental abruption
5. Fetal death in utero
6. Developmental anomalies
36
What are the dangers of marijuana use during pregnancy?
No apparent adverse effect
37
What are the dangers of cocaine use during pregnancy?
1. Mother (6)
2. Fetus (4)
Mother:
1. Can induce cardiac arrhythmias in mother
2. Can induce CNS damage in mothers
3. Uterine rupture
4. Hypertension
5. Seizures
6. Death
Fetus:
1. Placental abruption
2. IUGR
3. Preterm labour
4. Congenital abnormalities
38
What are the dangers of alcohol intake during pregnancy (5)?
Fetal alcohol syndrome - leads to:
1. Facial abnormalities
2. CNS dysfunction (microcephaly, mental retardation)
3. Growth retardation
4. Cardiac defects
5. Multiple joint anomalies
39
What are the dangers of smoking during pregnancy (5)?
1. Decreased fertility
2. Increased spontaneous abortion
3. Preterm birth
4. Perinatal mortality
5. Low birth weight infants
40
What are the dangers of neonatal exposure to cigarette smoke (4)?
Associated with:
1. Sudden infant death syndrome
2. Asthma
3. Respiratory infections
4. Attention deficit disorder
41
What are the risks of drug treatment in pregnancy?
What are the changes in pregnancy that alters the way drug absorption occurs?
(4)
1. Volume of distribution changes in pregnancy - plasma volume rises and total body water increases. This would be expected to decrease drug levels, but albumin concentrations decline so protein binding of many drugs is lower in pregnancy leading to an increase in circulating free/active drug levels
2. Metabolism and elimination are also altered in pregnancy. High steroid hormone levels affect hepatic metabolism and prolong the half-life of some drugs. Glomerular filtration rates rise, increasing the renal clearance of some drugs.
3. Teratogenicity of some drugs.
4. Drug absorption is altered in pregnancy. Gastric emptying and gastric acid secretion are reduced.
42
What affects the rate of drug transfer across the placenta from the mother to the fetus?
Governed by the solubility of the ionised molecules in fat and the thickness of the trophoblast.
43
What drugs cross the placenta to the fetus?
What drugs don't?
With the exception of large molecules (I.e. heparin), all drugs given to the mother cross the placenta to some degree.
44
How does the rate of drug transfer passing from mother to fetus change in 2nd half of pregnancy?
The trophoblast becomes thinner, whereas the placental area increases in size; drugs therefore pass through more rapidly.
45
During which period of time is the biggest risk of teratogenicity of a drug to the fetus?
During organogenesis i.e. 17-70 days post-conception
After this, the risk of major birth defects is almost negligible
46
What are 5 drug prescribing principles for pregnant women?
1. Only use medications if absolutely indicated
2. If possible, avoid initiating therapy during the first trimester
3. Use lowest effective dose
4. Single-agent therapy is preferable
5. Select safe medication
47
How many routine antenatal appointments do non-complicated parous women have vs non-complicated multiparous women?
Parous = 10
Multiparous = 7
48
At how many weeks do pregnant women have their antenatal screening appointments throughout their pregnancy and briefly mention what that appointment is for?
*the extra appointments only for parous women
By 10 weeks = booking appointment
16 weeks = Standard screen
18-20 weeks = Anomaly scan if she chooses. (Another one can be offered at 32 weeks if placenta extends across the internal cervical os)
*25 weeks = Standard screen
28 weeks = Standard screen - Offer 2nd screening for anaemia and atypical red-cell alloantibodies
- Offer anti‑D prophylaxis to rhesus‑negative women
- Investigate a haemoglobin level below 10.5 g/100 ml and consider iron supplementation, if indicated
* 31 weeks = Standard screen
- Review and discuss results of screening tests from previous appointment
34 weeks = Standard screen
- Discuss preparation for labour and birth, including information about coping with pain in labour and the birth plan. Discuss recognition of active labour
- Offer a 2nd dose of anti-D to Rhesus-negative women
- Review, discuss and record the results of screening tests undertaken at 28 weeks
36 weeks = Standard screen
- Check lie and presentation of baby (Offer ECV if breech)
- Discuss with the mother:
1. Breast feeding technique and good management practises
2. Care of the new baby
3. Vit K prophylaxis and new born screening tests
4. Postnatal self-care
5. Awareness of "baby blues" and post-natal depression
38 weeks = Standard screen
-Give info on options for management of prolonged pregnancy, with opportunity to discuss issues and ask qs
* 40 weeks = Standard screen
- Give info on options for management of prolonged pregnancy, with opportunity to discuss issues and ask qs
41 weeks = Standard screen
- A membrane sweep should be offered
- Induction of labour should be offered
49
What 3 standard screening tests are done at every antenatal visit?
1. Blood pressure
2. Urine dip for proteinuria
3. Symphysis-fundal height
50
What are the general points that should be considered at each antenatal routine screening appointment? (4)
1. Healthcare providers should remain alert to risk factors, signs or symptoms of conditions that may affect the health of the mother and baby, such as domestic violence, pre-eclampsia and diabetes
2. Give information, with an opportunity to discuss issues and ask questions at every appointment
3. Ask if mother has been feeling fetal movements
4. Once the fundus of the uterus can be palpated abdominally, the fetal heart can be detected with a hand held Doppler at each visit
51
At the booking appointments by 10 weeks, what topics needs to be discussed (9)?
1. How the baby develops during pregnancy
2. Nutrition and diet, including vitamin D supplementation
3. Exercise, including pelvic floor exercises
4. Antenatal screening, including risks and benefits of the screening tests
5. Pregnancy care pathway
6. Place of birth
7. Breastfeeding, including workshops
8. Participant‑led antenatal classes
9. Maternity benefits
52
At the booking appointments by 10 weeks, what screening is done? (5)
1. Weight and height -> BMI
2. Hx to ask about physical or mental illnesses incase further assessment or care is necessary
3. USS offered between 10 weeks-13 weeks 6 days to determine gestational age and screen for Down's syndrome.
4. Blood tests
- Checking blood group, rhesus D status and screening for haemoglobinopathies, anaemia, red‑cell alloantibodies, hepatitis B virus, HIV, rubella susceptibility and syphilis
5. Urine tests
- proteinuria and screen for asymptomatic bacteriuria
53
What do blood tests that done at the booking appointment check for (9)?
1. Blood group
2. Rhesus D status
3. Screening for haemoglobinopathies
4. Anaemia
5. Red‑cell alloantibodies
6. Hepatitis B virus
7. HIV
8. Rubella susceptibility
9. Syphilis
54
What do urine tests done at the booking appointment check for (2)?
1. Proteinuria
| 2. Asymptomatic bacteriuria
55
What are some indications for USS in pregnancy?
0-10 weeks: Scan if doubt about gestational age
11-13 weeks: Scan for nuchal fold thickness for trisomy 21, 13 and 18
18-20 weeks: Fetal anomaly scan
21-30 weeks: Detection of multiple pregnancy, fetal death, antepartum, haemorrhage, clinical polyhydramnios
31-40 weeks: Assessing fetal growth, maternal disorders e.g pre-eclampsia, antepartum haemorrhage etc
56
What are the 3 limitations of using USS in pregnancy?
Degree of success is influenced by:
1. Maternal habitus
2. The skill of the operator
3. The size of the anomaly
57
What are the 5 techniques for fetal monitoring?
1. Cardiotocography (CTG)
2. Fetal movements
3. Biophysical profile
4. Serial US examinations
5. Fetal blood flow velocity
58
What are the goals of fetal monitoring (2)?
1. Early identification of a fetus at risk for preventable morbidity or mortality due specifically to uteroplacental insufficiency
2. Detection of progressive fetal asphyxia which can lead to fetal death or handicap
59
What does CTG measure?
Fetal heart rate pattern with time
60
What is the mneumonic for reading a CTG?
```
DR. = determined risk e.g. preterm labour/decreased fetal movement?
C. = contractions/Braxton Hicks
BR = base rate. Normal is 110-160 beats/min
V = variability. Normal is >5 bpm (jagged line).
A = acceleration. Normal is >15 beats in 15 secs
D = deceleration, drops in heart rate from baseline
O = Overall
```
61
What is the normal heart rate for a fetus?
110-160 beats/min
62
When does a mother usually start to feel fetal movements?
2nd half of pregnancy
63
At term, how often does a fetus move on average?
31 times per hour with a range of 16-45 with the longest interval between movements 50-75 mins
64
How long is it ok for fetal movements to be absent during sleep cycles?
20-40 mins, rarely exceeding 90 mins
65
What would you advise a woman who does not feel her fetus moving?
She should lie on her left side and contact her maternity care giver immediately if they do not feel 10 contractions in the next 2 hours.
66
What is the biophysical profile of a fetus?
What variables is it made up of? (5)
Sonographic scoring system designed to assess fetal well-being.
Five variables:
1. CTG
2. Fetal movement
3. Fetal tone
4. Amniotic fluid volume
5. Fetal breathing.
67
How is the biophysical profile of a fetus scored?
2 points awarded if variable is present or normal, 0 if absent or abnormal
A normal score is 8-10, lower than a score of 6, suspect asphyxia.
68
What are disadvantages of a biophysical profile of a fetus?
Time-consuming, and no evidence to suggest it is better than CTG and Doppler blood-flow testing
69
At what intervals can a fetus be monitored with serial USS at?
3 weekly intervals
70
What 3 parameters are measured in serial US examinations of the fetus?
1. Abdominal circumference
2. Head circumference
3. Femur length
Plotted on a centile chart
71
How does fetal blood flow velocity work? (3)
1. Umbilical artery Doppler velocimetry measurements reflect resistance to blood flow from the fetus to the placenta
2. Absent or reversed diastolic flow is associated with poor perinatal outcome in the setting of IUGR and urgent delivery should be considered.
3. Abnormal flow in the middle cerebral artery and ductus venosis can help in the timing of delivery of IUGR fetuses.
72
In antenatal screening for genetic abnormalities, which 3 syndromes are they screening for?
Trisomy 21, 13 and 18
73
What are the 3 antenatal screening regimens offered for detection of genetic abnormalities?
1. Measurement of pregnancy-associated plasma protein A and free beta-human chorionic gonadotrophin (beta-hCG) levels at 9-13 weeks gestation. In Down's, PAPP-A may be low and beta-hCG may be raised.
2. Nuchal thickness of the fetus between 10 weeks and 13 weeks 6 days on USS is compared with maternal age. Increased thickness can indicate oedema due to heart failure, suggesting Down syndrome.
3. Combines levels of beta-hCG, alpha-fetoprotein (AFP), free unconjugated oestriol and inhibin A (in some centres), measured between 15-20 weeks. Oestriol and AFP levels are lower in Down's and beta-hCG are raised.
74
If there is a higher risk of Down's syndrome (>1/200 to 1/250), what 2 diagnostic tests can be done to confirm it and at what gestation?
1. Chorionic villus sampling (CVS) at gestation 11-14 weeks
| 2. Amniocentesis from 15 weeks gestation
75
How does CVS work?
A sample of chorionic tissue is removed from the placental edge by aspiration via a needle transabdominally with US guidance.
A karyotype is then made within 24-48 hours.
76
How does amniocentesis work?
The needle is pushed through the abdominal wall and into the amniotic sac, guided by US, and a sample of amniotic fluid is removed. The fetal cells obtained are cultured and harvested, and a karyotype is made of the chromosomes in 2 weeks.
77
What is the advantage of CVS over amniocentesis and a limitation?
CVS is quicker than amniocentesis but less accurate
78
When does screening for open neural tube defects occur antenatally?
During screening for Downs and the use of 2nd trimester USS
79
How does Rhesus disease occur? What antibodies are involved?
| 3
1. Occurs when a Rh-negative woman is exposed to Rh-positive blood from their fetus, producing an antibody response
2. The initial immune response is IgM, which does not cross the placenta so the index pregnancy is not affected.
3. Following sensitisation after birth, subsequent pregnancies will trigger an IgG response which will cross the placenta and cause haemolysis
80
What is given to prevent Rhesus disease?
Passive immunisation 72 hours before exposure with anti-D IgG can destroy fetal erythrocytes in maternal circulation before it evokes a maternal immune response.
81
What is important with regards to the timing of passive immunisation to prevent Rhesus disease? (5)
It needs to be given at the right time:
1. Threatened/spontaneous miscarriage
2. Invasive procedures
3. Routinely antenatally at 28 and 34 weeks gestation
4. Routinely at delivery if infant is Rh D positive
5. It should be administered as close to the sensitising event as possible and within 72 hours.
82
What is important with regards to the amount of passive immunisation to prevent Rhesus disease?
It must be sufficient to remove all fetal cells from the maternal circulation
83
What test can be done to check if enough passive immunisation has been given to prevent Rhesus disease?
The Kleihauer-Betke test identifies fetal cells in maternal blood, so can be used to determine the volume of FMH and to assess whether additional doses of anti-D are required.
84
What is the WHO definition of an antepartum haemorrhage?
A significant bleed from the birth canal occurring after the 24th week of pregnancy
85
What are 3 causes of antepartum haemorrhage from the vagina?
1. Haemorrhage from the placental site and uterus:
- Placenta praevia
- Placenta accreta
- Placenta abruption
2. Lesions of the lower tract
- heavy show/onset of labour
- cervical ectropion/carcinoma
- polyps
- vulval varices
- trauma
- infection
3. Bleeding from fetal vessels including vasa praevia
86
What is the mechanism of placenta praevia and how does it cause bleeding? (2)
1. The placenta is implanted either partially or wholly in the lower uterine segment and lies below (praevia) the fetal presenting part.
2. The bleeding occurs when the lower uterine segment increases in length and shearing forces between the trophoblast and maternal blood sinuses occur.
87
At what gestation does the first episode of bleeding occur with placenta praevia?
Usually occurs after the 36th gestational week
88
What are risk factors for placental praevia (3)?
Risk increases with:
1. Multiparity
2. With each C-section
3. Multiple pregnancy
89
What are the features of bleeding due to placenta praevia (4)?
What are 2 other common clinical features?
Bleeding is:
1. Painless
2. Causeless
3. Recurrent
4. Unpredictable - usually first bleed is mild but can vary to being massive and life-endangering
Malpresentation of fetus
Normal uterine tone
90
How is placenta praevia diagnosed?
By USS
- at 18 weeks a low-lying placenta may be identified. Vaginal delivery may still be possible as the lower uterine segment does not develop fully until late in 3rd trimester
- Repeat USS at 32nd week or earlier if bleeding occurs
91
What is the management of mild-moderate bleeding due to placenta praevia (5)?
1. On first episode of bleeding, bleeding is usually mild-moderate, but admit to hospital. Do not VE
2. Check patients vital signs, amount of blood loss
3. Cross-match blood in case transfusion needed
4. USS to confirm diagnosis
5. CTG to determine fetal status
92
What is the management of severe bleeding due to placenta praevia?
1. Urgent delivery (C-section) of the baby and placenta is required, irrespective of the gestational age of the fetus
2. Cross-match blood in case transfusion needed
93
What is the management of moderate bleeding due to placenta praevia where the fetus is <36 weeks?
Expectant treatment where the patient stays in hospital until fetal maturity is adequate and transfusion ready for when necessary.
94
In general, how do grade 1+2 and 3+4 placenta praevia require delivery?
Grade 1+2 = Normal vaginal delivery
Grade 3+4 = C-section
Blood cross-matched and ready during delivery
95
What are 2 complications of placenta praevia?
1. During episodes of heavy bleeding, the fetus can die from hypoxia.
2. Following birth, post-partum haemorrhage may occur if the trophoblast has invaded the poorly supported veins of the lower uterine segment. Oxytocics are given.
96
What are 4 grades of placenta praevia?
Grade 1: Placenta encroaches on lower segment but not on internal os
Grade 2: Placenta reaches internal os
Grade 3: Placenta covers internal os with some placental tissue in upper segment
Grade 4: All the placenta is in lower segment with central portion close to cervical os
97
Why should a VE not be performed in suspected placenta praevia?
It can disrupt the placenta and cause excessive bleeding
98
What is placenta accreta?
Morbid adherence of the placenta
99
What is the most common cause of placenta accreta?
Previous C-section
If the placenta implants over a uterine scar from a previous C-section, the trophoblast can penetrate through the scarred decidua and myometrium, becoming morbidly adherent.
100
What is the management of placenta accreta?
Unless the area of adherence is small, the woman will need an immediate Caesarean hysterectomy to preserve her life
101
What is a placental abruption?
Haemorrhage resulting from premature separation of the placenta
102
What are risk factors for placental abruption (7)?
1. Social deprivation
2. Dietary deficiencies especially folate deficiency
3. Smoking
4. Hypertensive disease
5. Maternal thrombophilia
6. Fetal growth restriction
7. Male fetus
103
What is the main fetal affect of placental abruption?
High perinatal mortality rate
104
What are the 3 types of abruption?
1. Revealed - bleeding appears in vagina
2. Concealed - bleeding is retained behind placenta
3. Mixed
105
Why is the classification of abruption as revealed/concealed/mixed unhelpful?
Classification is made after delivery when concealed clot is discovered
106
What are 4 clinical features of placental abruption?
1. Pain
2. Vaginal bleeding of variable amounts
3. Increased uterine activity
4. Uterus may be tense and hard
107
What factors do the prognosis of the fetus depend on in placental abruption?
1. Extent of placental separation
| 2. Inversely proportional to the interval between onset of the abruption and delivery of the baby
108
How is the diagnosis of abruption made?
History and examination
1. History of vaginal bleeding
2. Abdominal pain
3. Increased uterine tonus
4. Commonly, presence of a longitudinal lie of a fetus
109
What is the general management of placental abruption? (that is not acute)
(7)
1. Admit patient to hospital
2. Diagnosis made on history and exam
3. USS to assess fetal growth and wellbeing
4. Manage conditions associated with abruption e.g. hypertension
5. IV infusion of saline/transfusion
6. Cross -match blood
7. Urinary catheter essential to monitor urinary output
110
What is the immediate management if the haemorrhage is severe in placental abruption? (2)
1. Resuscitation of mother is first prerequisite
| 2. After, address fetal condition
111
If the fetus is preterm in an abruption, how do you manage this if the mother and fetus are clinically stable?
Aim to monitor in hospital and prolong the pregnancy until fetus is mature enough
112
In the management of an abruption, if the fetus is alive without features of compromise, close to term, or the fetus is dead, what is done?
Surgical induction of labour performed as soon as possible and where necessary, uterine activity stimulated with a syntocinon infusion
113
If in an abruption, the fetus becomes compromised, what should be done?
Fetal heart monitored and C-section done
114
What pain relief is used in abruption? What is not used?
Opiates
Epidural anaethesia should not be used until a clotting screen is available
115
What are the 4 complications of placental abruption?
1. Afibrinogenaemia
2. Hypovolaemia from blood loss
3. PPH
4. Renal tubular or cortical necrosis
116
What is afibrinogenaemia?
When a clot from a severe abruption causes the release of thromboplastin into the maternal circulation. This can lead to a disseminated intravascular coagulation, where there is consumption of coagulation facturs including platelets, with the development of hypo and afibrogenaemia
117
What is the cause of renal tubular or cortical necrosis in placental abruption?
Complication of undertreated hypovolaemia and DIC
118
What is the aetiology of gestational diabetes? (2)
1. During pregnancy, the placenta secretes substances that have an anti-insulin action, including human placental lactogen (hPL), progesterone, human chorionic gonadotrophin (hCG), cortisol, glucagon and cytokines.
2. If the mother's pancreas is unable to produce the additional insulin required to counteract this effect, the woman will develop hyperglycaemia (gestational diabetes)
119
What are 4 main risk factors of gestastional diabetes that NICE recommends should be used in screening?
1. Previous large infant (above 95th centile for gesational age)
2. Previous gestational diabetes
3. First-degree relative with diabetes
4. Obesity (BMI >30)
120
When one or more risk factor for gestational diabetes is indicated, what investigation should be done?
75g OGTT at 28 weeks
or if very high risk:
Early 2nd trimester and then repeated at 28 weeks
121
How is an OGTT done? (3)
1. Fasting glucose measured
2. 75g loading dose of glucose given
3. Glucose level taken at 2 hours post-sugar load
122
What are the normal values for an OGTT?
1. Fasting
2. 2 hour value
1. Fasting = <7.0mmol/L
| 2. 2 hour value = <7.8mmol/L
123
What is the effect of gestational diabetes on the fetus (7)?
1. Increased risk of polyhydramnios
2. Increased risk of macrosomia
3. Increased risk of stillbirth
4. In vaginal birth, increased of shoulder dystocia and instrumental birth
5. More likely to need admission to neonatal unit
6. Increased risk of neonatal hypoglycaemia
7. Increased risk of obesity and diabetes in later childhood
124
What is the pathophysiology of macrosomia and neonatal glycaemia?
Maternal glucose, but not insulin, can readily cross the placenta to the fetus, causing the fetal pancreas to secrete extra insulin
125
What are the effects of gestational diabetes on the mother (5)?
1. Increased risk of recurrent infections
2. Increased risk of pre-eclampsia
3. Extended perineal tears more common
4. More likely to need a C-section
5. May unmask T2DM
126
What pre-pregnancy advice would be given to a woman with a hx of gestational diabetes or are known diabetics (4)?
1. Consultant led care to explain to the women the reasons for meticulously maintaining her blood glucose at levels before conception.
2. Encourage her to take folic acid to reduce risk of neural tube defects
3. Assessment of diabetic complications such as retinopathy and nephropathy
4 .Women taking oral hypoglycaemic agents should be switched to insulin therapy
127
What is the management of gestational diabetes during pregnancy? (2)
1. Many women with gestational diabetes can control glucose levels by diet and exercise alone, but up to 60% may need therapy: metformin and glibenclamide are increasingly used/insulin therapy
2. Serial growth scans advised to alert to fetal macrosomia or malformations
128
During pregnancy, what are the ideal fasting and 2-hour post-prandial glucose levels in a woman with gestational diabetes?
Fasting: between 4.0-6.0 mmol/L
2-hour post-prandial: between 6.0-8.0 mmol/L
129
What precautions need to be taken regarding delivery of a fetus where the mother has gestational diabetes? (5)
1. Delivery at term to reduce risk of still birth
2. If metabolic control has been inadequate and polyhydramnios or fetal macrosomia is present, delivery at 38 weeks is indicated
3. During labour, blood glucose should be regularly measured and hyperglycaemia treated to reduce risk of neonatal hypoglycaemia
4. The risk of shoulder dystocia is increased with bigger babies, so C-sections are recommended if there is significant macrosomia.
5. As the mothers insulin requirements quickly return to pre-pregnancy levels after delivery, monitoring of blood glucose levels is important
130
When can diabetic therapy be discontinued in a woman with gestational diabetes?
With the delivery of the placenta
131
Following delivery of a baby of a gestational diabetic mother, what precautions need to be taken regarding the newborn? (3)
1. Following delivery, the baby needs to be assessed by the neonatologist. They may need early feeding with oral glucose to prevent hypoglycaemia. The blood glucose levels should be monitored before each feed for the next 2 days.
2. Babies of diabetic mothers who had difficulty controlling their blood glucose during pregnancy are likely to have poor temperature control, to feed slowly and be jaundiced, hypocalcaemia and hypomagnesaemic.
3. If born before term, they are more likely to have RDS because of delayed resorption of lung fluid, causing transient tachypnoea in the newborn baby.
132
What advice should be given to women with gestational diabetes after delivery? (3)
1. Advised that they may develop overt diabetes, so regular testing should be done at least every 2 years if the OGTT is normal
2. They should be encouraged to make lifestyle changes, I.e. diet, avoid being overweight, exercising, avoid smoking and be checked annually for hypertension.
3. Women have a 50% chance of developing gestational diabetes in future pregnancies. If they are planning to get pregnant again, they should test for hyperglycaemia before conception or early pregnancy.
133
What is the definition of hypertension in pregnancy?
Systolic bp of over 140mmHg
or
Diastolic bp of over 90mmHg on two or more occasions
134
At what Korotkoff sound is the diastolic pressure measured at in pregnancy?
5th
135
What is the definition of proteinuria?
Presence of urinary protein in concs greater than 0.3g/L in a 24 hour collection
or
In concs greater than 1g/L on a random sample on 2 or more occasions at least 6 hours apart
136
What are the various types of hypertension in pregnancy (6)?
1. Gestational hypertension
2. Pre-eclampsia
3. Eclampsia
4. Chronic hypertension
- Essential hypertension
- Secondary hypertension
5. Superimposed pre-eclampsia or eclampsia
6. Unclassified hypertension
137
What is gestational hypertension?
Hypertension that arises after 20 weeks gestation without features of pre-eclampsia, and resolves within 3 months of delivery
138
What is the management of gestation hypertension? (3)
1. Bp needs to be carefully monitored to exclude development of pre-eclampsia
2. Conservative measures started i.e. rest + lifestyle changes
3. If bp exceeds 140/90 (or 150/100) then anti-hypertensive therapy is started, with the objective of sbp between 110-140 mmHg and dbp between 80-90 mmHg
139
What is the prognosis of gestation hypertension?
Good prognosis - 25% go on to develop pre-eclampsia
140
What are the 2 types of chronic hypertension?
1. Essential hypertension
- Sbp>/=140mmHg and/or dbp>/=90 prior to conception or in first half of pregnancy without an apparent underlying cause
2. Secondary hypertension
- Hypertension associated with renal, renovascular and endocrine disorders and aortic coarctation e.g. renal artery stenosis and pheochromocytoma
141
What is the definition of essential hypertension during pregnancy?
A bp >/= 140/90 mmHg in the absence of a secondary cause, present before pregnancy or detected before the 20th week of gestation.
142
What needs to be taken into consideration when measuring bp during pregnancy (2)?
1. In the first half of pregnancy, the small physiological fall in bp in the first half of pregnancy may be exaggerated in women with chronic hypertension, causing cases to be missed.
2. Diastolic pressure is taken at the 5th Korotkoff sound.
143
What is the management of essential hypertension during pregnancy? (3)
1. Resting - to maintain a good blood supply to uterus
2. Control bp
- Anti-hypertensives
3. Terminate pregnancy if patients condition deteriorates markedly or if fetus fails to grow adequately in last quarter of pregnancy
144
What anti-hypertensives are safe in pregnancy? (5)
1. Methyldopa
2. Hydralazine (oral)
3. combined alpha and b-blockers labetalol
4. a-blocker i.e. prazosin (oral)
5. CCB e.g. nifedipine
145
What anti-hypertensives are not safe in pregnancy and why? (2)
1. Diuretics - reduce plasma volume and uteroplacental blood flow
2. ACEI - teratogenic
146
What is the definition of pre-eclampsia? (6)
Hypertension, detected after 20 weeks gestation, followed by one or more of:
1. Proteinuria
2. Renal insufficiency - serum/plasma creatinine or oligouria
3. Liver disease – raised serum transaminases
4. Neurological problems – convulsions (eclampsia), hyperreflexia with clonus, severe headaches with hyperreflexia, persistent visual disturbances
5. Haematological disturbances – thrombocytopenia, DIC, haemolysis
6. Uteroplacental dysfunction – Fetal growth restriction
147
What is the general pathophysiology of pre-eclampsia? (2)
1. Arteriorlar vasoconstriction, particularly in the vascular bed of the uterus, placenta and kidneys
- the secondary invasion of maternal spiral arteries by trophoblasts are impaired, so they remain high resistance vessels, which leads to hypoxia and damage to the placenta and its function
2. DIC
- There is an increase in fibrin deposition and in circulating fibrin degradation products as a result of increased fibrin production and impaired fibrinolysis
148
What are the placental infarcts that occur more extensively in pre-eclampsia? (5)
1. Increased syncytial knots or sprouts
2. Increased loss of syncytium
3. Proliferation of cytotrophoblast
4. Thickening of the trophoblastic basement membrane
5. Villous necrosis
149
What are the symptoms of pre-eclampsia? (5)
```
1. Usually asymptomatic
However the following symptoms should not be overlooked:
2. Frontal headache
3. Blurring of vision
4. Sudden onset vomiting
5. Right epigastric pain
```
150
In the management of gestational hypertension and pre-eclampsia, how is monitored at each antenatal visit? (2)
1. BP measured in constant position at each antenatal visit
- if elevated, it should be repeated after short period of rest. If it remains high, continuing close observation is essential
2. Urine is also measured at every visit
- Development of more than 1+ proteinuria or a spot urinary/creatinine ratio of more than 30mg/mmol is an absolute indication of hospital admission
151
If hypertension in pregnancy persists or worsens, and the mother is at or close to term, what should be done?
Fetus should be delivered
152
At what blood pressure in pre-eclampsia warrants anti-hypertensive treatment?
150/100
153
What is given to a woman who is less than 34 weeks gestation and her hypertensive disease is severe enough that early delivery is contemplated?
Steroids - betamethazone 11.4mg IM, 2 doses 12-24 hours apart to minimise RDS< intraventricular haemorrhage and necrotising neterocolitis
154
What maternal observations need to be done for a woman with pre-eclampsia? (3)
1. 4-hourly measurement of bp until it has returned to normal
2. Regular urine checks for proteinuria
3. Maternal serum screenng for pre-eclampsia
155
What fetoplacental investigations need to be done for pre-eclampsia? (3)
1. Serial ultrasounds
- Measurements of fetal growth every 2 weeks
- Measurements of liquor volume to to twice weekly
2. Doppler flow studies up to twice weekly
3. Antenatal CTG
156
What does a Doppler flow study measure? (4)
Serial Doppler waveform measurements in the fetal umbilical artery and maternal uterine artery
1. Assesses increasing vascular resistance indicative of uteroplacental blood flow typical of pre-eclampsia
2. Assesses for poor diastolic flow in uterine artery waveform in 2nd trimester - warns of increased risk of pre-eclampsia and IUGR
3. Assesses an increase in systolic/diastolic flow ratio in the fetal umbilical artery due to a progressive diminution of flow in diastole warning of worsening placental vascular disease in 3rd trimester
4. Absent or reverse flow in diastole indicates severe vessel disease, probably fetal compromise and delivery of fetus should be considered if CTG abnormal
157
On a CTG, what are indications of fetal wellbeing? (2)
1. Fetal heart rate in relation to uterine contractivity is useful indication
2. Presence of fetal deceleration and loss of baseline variability may indicate fetal hypoxia
158
What are the complications of pre-eclampsia relating to:
1. Fetus
2. Mother
3. Placenta
1. Fetus
- IUGR
- Hypoxia
- Death
2. Mother
- Associated with fall in blood flow to various organs leading to: renal failure, hepatic failure, intrahepatic haemorrhage, seizures, DIC, ARDS, cerebral infarction, heart failure
3. Placenta
- Infarction
- Abruption
159
What is HELLP syndrome?
What does it stand for?
A severe manifestation of pre-eclampsia occuring in a variant known
H - haemolysis
EL - elevated liver enzymes
LP - low platelet count
160
What is the pathophysiology of HELLP syndrome?
Extension of DIC causing haemolysis and low platelets, and the endothelial dysfunction/hypoxia in liver resulting in release of liver transaminases especially ALT
161
What are complications of HELLP syndrome?
Thrombocytopenia is often rapidly progressive and if left to become severe may result in haemorrhage into the brain and liver
162
What is the management of HELLP syndrome?
It demands intervention and termination of pregnancy as soon as any acute manifestations like hypertension are controlled
163
In a pregnancy complicated by hypertensive disease, what reasons would a warrant a termination of pregnancy?
1. Maternal (6)
2. Fetal/placental (4)
Maternal:
1. Gestation >37 weeks
2. Uncontrollable bp
3. HELLP syndrome
- rising liver dysfunction
- falling platelets
- falling haemoglobin due to haemolysis
4. Deteriorating renal function
5. Eclampsia
6. Acute pulmonary oedema
Fetal/placental
1. Fetal compromise on CTG tracing
2. Absent or reversal of end diastole flow in the umbilical artery
3. No fetal growth over more than 2 weeks
4. Placental abruption
164
What is given for the prevention of pre-eclampsia? (3)
1. Prophylactic low dose aspirin therapy started if feasible before 16 weeks
2. Calcium supplements
3. Vitamin B2, C or E has not been shown to be effective for prevention of pre-eclampsia
165
In which patients does eclampsia usually occur? (2)
1. Those with severe pre-eclampsia or imminent eclampsia
| 2. Those with gestational proteinura has been superimposed on chronic hypertension
166
What is the pathophysiology of eclampsia? (2)
1. Pathophysiology of severe pre-eclampsia that is more marked
2. Vasospasm is intense, with tissue hypoxia, GFR is further reduced and urinary output falls. Intracellular water retention impedes cellular metabolism and cerebral oedema may occur, blood viscosity increases, platelet levels fall and coagulation defects arise.
167
What are the signs and symptoms of eclampsia? (5)
1. The convulsion is preceded by a disorientation stage during which the woman becomes restless, twitches and develops spasmodic respiration.
2. Within a minute, she enters the tonic stage of the convulsion: back arches, hands clench, grimaces, breathing ceases leading to cyanosis, and tongue-biting may occur.
3. Then she passes into the clonic stage of the convulsion where the body jerks uncontrollably, frothy saliva may fill her mouth and breathing is stertorous.
4. Finally she becomes comatose which may last for an hour or more, or recurrent convulsions may occur.
5. The convulsions can occur in pregnancy or a few hours after birth.
168
What are the 3 aims of management of eclampsia?
1. To control the fits by relieving the generalised vascular spasm and decreasing sensitivity of the brain to stimuli
2. Reduce the bp to prevent cerebral haemorrhage
3. To deliver the fetus
169
What is the immediate management of eclampsia? (7)
1. Admission to ITU
2. Protect the airway - seizures are usually self-limiting
3. Magnesium sulphate iv or im for control of fits thereafter, reduces risk of recurrent seizures
4. Furosemide iv in cases of heart failure
5. Control of bp: hydralazine iv is useful in acute settings, or iv labetalol
6. Epidural analgesia relieves the pain of labour and helps to control bp by causing vasodilatation in the lower extremities
7. Termination of pregnancy
170
Once good control of bp and convulsions has been obtained in eclampsia, what needs to be done?
Pregnancy should be terminated
-depending on gestation/health/presentation of fetus, delivery is C-section or induction of labour (prostaglandins or amniotomy)
171
What needs to be given to the mother after birth of the baby in eclampsia and why?
IV syntocinon as PPH may occur after birth
172
What are the complications of eclampsia?
1. Fetus (1)
2. Mother (2)
Fetus:
1. Intrauterine death
Mother:
1. Death from cerebral haemorrhage
2. Renal and hepatic failure
173
What needs to be monitored in a woman with eclampsia? (4)
1. Constant monitoring of airway
2. BP
3. Fluid balance strictly monitored
4. Urine output
174
For how long do the risks of eclampsia continue after delivery?
7 days
175
If fitting occurs for the first time 48 hours after delivery of the fetus in a woman with eclampsia, what must be considered? (2)
An alternative diagnoses such as:
1. Epilepsy
2. Intracranial pathology such as cortical vein thrombosis
176
What is the management of a woman with eclampsia after delivery? (4)
1. Maintain the patient in a quiet environment under constant observation
2. Maintain appropriate levels of sedation. Continue magnesium sulphate infusion for 24 hours after last fit
3. Continue anti-hypertensive therapy until blood pressure is normal. Usually involves transferring to oral medication
4. Strict fluid balance charts kept, bp and urine output observed on an hourly basis
177
How long can hypertension persist in a patient with eclampsia after delivery?
6 weeks
178
What is the prognosis of pre-eclampsia or eclampsia?
Most will completely recover and return to normal, they need to have review of hypertension or proteinura as it may indicate underlying renal disease
179
How do dizygotic twins arise?
When 2 separate ova are fertilised by 2 different sperm
| Each have their own placenta, amnion and chorion
180
How can you differentiate between a monochorionic diamniotic twin or dichorionic diamniotic twin?
The presence of lambda (chorion in between membranes) or T (absence of chorion in between membranes)
181
What are risk factors for DZ twins (6)?
1. Older mother
2. Increasing parity
3. Maternal family history of twins
4. African origin, less common in Asian races
5. IVF
6. Drugs that induce ovulation e.g. gonadotrophin therapy
182
How do monozygotic twins arise?
A single fertilised ovum divides to form 2 embryos
183
What are the 2 forms of DZ pregnancies?
1. Dichorionic diamniotic with separate placentas
| 2. Dichorionic diamniotic with fused placenta
184
What are the 4 forms of MZ pregnancies? Which is most common*?
1. Dichorionic diamniotic with separate placentas
2. Dichorionic diamniotic with fused placenta
3. Monochorionic diamniotic*
- single placenta and chorion
- two amnions
4. Monochorionic monoamniotic
- single placenta and chorion
- single amnion
185
How is multiple pregnancy diagnosed and when? (2)
Diagnosed by 18-20 weeks on USS
or if not, other signs are:
1. An abdominal girth and uterine size larger than that expected from the period of amenorrhoea
2. Palpation shows an excess of fetal parts and two fetal heads detected
186
What are complications of multiple pregnancy unrelated to the zygosity?
1. Mother (4)
2. Fetus (3)
Mother
1. Early onset and/or increased nausea and vomiting
2. Anaemia - metabolic demands in multiple pregnancy higher
3. Antepartum haemorrhage due to increased risk of abruption and placenta praevia
4. Increased incidence of gestational hypertension, pre-eclampsia and eclampsia
Fetus
1. Miscarriage - resorption of a fetus between 6-10 weeks occurs in over 15% of twin pregnancies (vanishing twin syndrome). Incidence of threatened and actual miscarriage higher in twins
2. IUGR especially in one twin
3. Preterm labour - most important complication. Onset of labour occurs before 37 weeks in over 40% of twin pregnancies.
187
What are the complications of multiple pregnancy related to the zygosity? (3)
1. Twin-to-twin transfusion syndrome (TTTS)
2. Twin reversed arterial perfusion syndrome (TRAP or acardiac twin) - rare
3. Monamniotic and conjoined twinning
188
What is TTTS?
Arises in 10-15% of monochorionic diamniotic twin pregnancies.
Arises from vascular communications in the placenta connecting the two fetal circulations. There is a net flow of blood from one twin (donor) to the other (recipient) with consequent oliguria/polyuria causing polyhydramnios in the recipient and oligohydramnios in the donor. As the condition advances the haemodynamic status is affected resulting in a high rate of fetal loss.
189
What is twin reversed arterial perfusion syndrome (TRAP or acardiac twin)?
A severe variant of TTTS, where the twins blood systems are connected. One twin called the acardiac twin is severely malformed, where the heart is missing, as are other parts of its body. The other twin is usually normal in appearance, and is responsible for driving blood through both fetuses.
190
What is the management of multiple pregnancy? (4)
More complications in multiple pregnancy so mother needs extra antenatal care
1. The woman should be offered an USS at 10-13 weeks gestation to assess viability, chorionicity, to exclude major congenital malformation and to measure nuchal translucency
2. If monochorionicity is detected, then the mother should be referred for specialist care because of possible complications
3. Otherwise, the mother should be seen at 2 weekly intervals from the time of diagnosis
4. The fetal growth should be monitored by USS every 2-3 weeks from the 30th week. If growth ceases and/or Doppler blood flow indices are abnormal, delivery should be expedited
191
What is the management of multiple pregnancies in labour? (2)
1. Check position of the fetuses on admission
2. Decision about method of delivery
-Delivery by C-section is indicated for the same reasons that exist for singleton pregnancies but threshold is lower
or
-vaginal delivery when labour is allowed to proceed normally
192
What are some indications for C-section in multiple pregnancy (3)?
1. Additional complications e.g. previous C-section scar severe pre-eclampsia etc
2. Preterm labour between 28-34 weeks
3. Malpresentation of 1st twin
193
What must be monitored/done in the vaginal delivery of multiple pregnancies? (5)
1. Make sure iv access is established early on
2. First twin can be monitored with a scalp electrode or by abdominal US, important to monitor both fetuses
3. After 1st twin is delivered, the lie and presentation of the 2nd twin must be immediately checked and fetal heart rate recorded
4. Membrane should be left intact until presenting part is well into pelvis and cord prolapse excluded
5. If fetal heart rate anomalies occur, then delivery should be expedited by forceps or breech extraction
194
What is important to give to a woman after vaginal delivery of twins and why?
Oxytocin as there is increased risk of postpartum haemorrhage
195
What are some complications of labour of multiple pregnancy (2)?
1. Abnormal lie leading to obstruction - indication for C-section
2. Occasionally, after the delivery of the first twin, the placenta separate and attempt to delivery before 2nd baby - C-section must be urgently performed
196
What are the different positions of the fetuses in twins and what %?
Both cephalic - 45%
Cephalic and breech - 25%
Breech and cephalic - 10%
Both breech - 10%
197
How does the incidence of breech presentation change with gestation?
At 30th week, 15% present as breech, but by term, only 3% present as breech. Most babies spontaneously turn and become cephalic.
198
What are the 3 types of breech presentation?
1. Breech with extended legs (frank)
2. Breech with flexed legs (complete)
3. Footling
199
Describe frank breech presentation
1. The legs lie extended along the fetal trunk and are flexed at the hips and extended at the knees
2. Buttocks present at pelvic inlet
200
Describe flexed breech presentation
Legs are flexed at the hips and the knees with fetus sitting on legs so both feet present to pelvic inlet
201
Describe footling breech presentation
One or both of the lower limbs are flexed and breech of the baby is above the maternal pelvis so the feet descends through the cervix into the vagina
202
What part of the fetus is used to define the position of the breech?
Fetal sacrum as denominator
203
What are the 4 risks of breech presentation?
1. Increased risk of cord compression and cord prolapse because of irregular nature of presenting part
2. Entrapment of the head behind cervix especially in preterm infants as trunk may deliver through an incompletely dilated cervix, resulting in entrapment of the larger head
3. The fetal skull does not have time to mould during delivery, so there is increased risk of intracranial haemorrhage
4. Trauma to viscera may occur during delivery, with rupture of spleen/gut if obstetrician handles the fetal abdomen
204
At what gestation does fetal presentation become of clinical importance?
32nd-35th week
205
How is breech presentation diagnosed? (4)
1. Palpation
- Lower pole of uterus is occupied by a soft, irregular mass
- Fundal area, there is a firm, smooth, rounded mass
2. Auscultation
- The fetal heart beat is loudest above the umbilicus
3. VE can be done
4. USS if there is any doubt
206
What is the management of breech presentation? (3)
1. External cephalic version (ECV) - indicated if breech after 36 weeks
If unsuccessful:
2. Elective C-section
or
3. Vaginal breech birth
207
Is it safer to deliver breech babies by C-section or vaginally?
The Term Breech Trial reported that in developed countries, delivery by C-section was the safest option, so now, fewer breech babies are being delivered vaginally. However the trial also found that at 2 years of age, there was no difference in the development between those delivered by C-section or vaginally.
Now, more specialist units are offering a vaginal birth where there are no other maternal contraindications and the birthweight of the fetus has been estimated to be in normal range.
208
What are indications for C-section delivery of a breech fetus (5)?
1. Birthweight <1.5kg or >4kg
2. Footling presentations
3. Where head is deflexed on US
4. No obstetrician available with vaginal breech delivery
5. Additional complications present such as severe pre-eclampsia, placental abruption or previous C-section
209
What is the sequence of events for an uncomplicated vaginal breech delivery (6)?
1. Buttocks enters pelvis in the transverse diameter of the pelvic brim. With full dilatation of the cervix, the buttocks descend deeply into the pelvis.
2. The buttocks rotate internally, the truck flexes laterally, and shoulders rotate so it can enter pelvis.
3. The buttocks advance, and if fetus has extended legs, the doctor may have to slip a hand along the anterior leg of the fetus and deliver it by flexion and abduction.
4. The shoulders enter the pelvis in its transverse diameter, causing external rotation of the buttocks so the fetal back is uppermost.
5. Fetal shoulders rotate internally, simultaneously, the buttocks rotate anteriorly through 90 degrees.
6. Descent of the fetal head occurs with flexion of it
210
In assisted vaginal breech delivery, what is the MSV manoevre? (2)
1. Baby is laid face down along doctor's arm. The 2nd and 3rd fingers are on the babies face, either side of the nose, and under its eyes to pull the face down to maintain flexion.
2. The 1st and 2nd finger of the other hand are placed on either side of the babies head across shoulders to enable downward traction. 3. Once hairline is visible, the baby is rotated upwards until mouth and nose are free.
211
In assisted vaginal breech delivery, what is the Lovset's manoevre? (3)
1. If arms do not deliver spontaneously, the doctor places their thumbs on either side of buttocks and fingers on iliac crests and gently rotates the body until the scapular is visible under the pubic arch.
2. The arm is released by sweeping the fingers along the arm and across the chest is the elbow is kept flexed.
3. Once arm is released, the baby can be rotated and the other arm released in the same way
212
What is the definition of prolonged pregnancy?
Any pregnancy that exceeds 294 days from the first days of the last menstural period in a woman with a regular 28 day cycle
213
What are the complications of prolonged pregnancy? (4)
1. Increased perinatal mortality, unexpected stillbirth
2. Intrapartum fetal distress
3. Increased operative delivery rate
4. Meconium aspiration
214
How is the management of prolonged pregnancy decided? (6)
1. Studies show increase in perinatal mortality after 39 weeks so close appraisal of every pregnancy at term to ensure continuation of pregnancy beyond 40 weeks is safe for fetus is needed
2. There is a postdate service where women present between 40-41 weeks for a CTG and amniotic fluid index (AFI) assessment
3. Those with low AFI are at increased risk of fetal morbidity so are offered induction are counselling
4. Those with normal liquor and CTG, studies have shown whether a woman is induced at 41-42 weeks or if labour is allowed to start spontaneously, the C-section rates are the same
5. Many units offer induction to all women by 41+5 weeks
6. Fetal monitoring with frequent CTG and liquor volume is needed
215
What is a problem that occurs with inducing labour in prolonged pregnancies? What is done?
The cervix is often unfavourable with a Bishop's score of less than 3
- Cervix should be prepared with prostaglandins or mechanical methods
- If this fails, delivery by C-section
Careful observation during labour is mandatory as there are high-risk pregnancies
216
What is the definition of preterm birth?
Delivery from 24 completed weeks up to 36 weeks and 6 days
217
What are 10 risk factors for preterm birth?
1. Previous preterm birth*
2. Socio-economic deprivation
3. Urogenital infections including chlamydia, bacterial vaginosis, gonorrhea and trichomoniasis (may cause PROM or promote myometrial activity
4. Smoking and passive smoking
5. Illicit drug use
6. Age <20 and >35
7. Low maternal weight and eating disorders
8. Uterine abnormalities and cervical incompetence
9. Multiple pregnancy
10. Pregnancy complications including antepartum haemorrhage
218
What are 4 immediate complications of preterm birth and 2 long-term complications?
Immediate:
1. RDS
2. Jaundice
3. Hypoglycaemia
4. Hypothermia
Long term:
1. Pulmonary dysplasia
2. Neurodevelopmental delay
219
What are 4 causes of death in very-low birth weight infants?
1. Infection
2. RDS
3. Necrotizing enterocolitis
4. Periventricular haemorrhage
220
What steps can be done to prevent a pre-term labour? (5)
1. Smoking and drinking cessation
2. Antibiotic therapy to eradicate infections
3. Progesterone as a depot im injection or pessaries reduces recurrence of preterm birth
4. Cervical cerclage increases the duration of pregnancy in women who have an incompetent cervix.
5. Increased contact with health professionals
221
What is the definition of preterm labour? (4)
1. Gestational period <36 completed weeks
2. Uterine contractions, occurring for at least 30 seconds and persisting for at least 60 mins
3. Cervix is >2.5cm dilated and >75% effaced (or progressive effacement and dilatation)
4. Confirmatory test = measure fetal fibronectin by a swab from cervix, which is released into cervical and vaginal secretion in preterm labour.
222
How accurate is the fetal fibronectin test in the confirmation of preterm labour? (3)
1. Negative test means it is unlikely that the woman will deliver within 7 days.
2. False positives can be due to coitus, vaginal infection and examination.
3. Its main benefit is to reduce the need to transfer women in possible preterm labour to tertiary units and/or to commence tocolytic therapy.
223
What is the management of preterm labour? (2)
1. Woman transferred to facility with NICU. If not, she should be given tocolytics to suppress uterine activity to allow her to be transferred to a facility with one.
2. After, there is a choice of suppressing uterine activity or permit labour to proceed.
224
In a woman with preterm labour, what factors would indicate that labour and delivery should proceed (3)?
1. >34 weeks
2. Bleeding in mother
3. Infection
225
What is the management of preterm labour of <34 complete weeks? (3)
1. Corticosteroids given to mother to prevent RDS in infant
2. Drug therapy (tocolytics) to prevent labour given to allow the steroid-induced lung maturation to occur
3. In this time, mother should be transferred to a hospital with NICU facilities
226
What factors would warrant a delay in labour? (4)
1. Pregnancy is <34 weeks and confirmation of preterm labour
2. Cervix is <5cm dilated
3. No evidence of abruptio placentae/chorioamnionitis
4. Fetus is alive and no potentially lethal malformations have been detected by US.
227
What tocolytics are available to delay delivery (3)?
1. b-adrenergic agonists
- Act on b2-adrenergic receptor sites on membranes of myometrial cells, inhibiting uterine activity
- Ritodrine, salbutamol and terbutaline
2. Prostaglandin synthetase inhibitors
- Inhibit prostaglandin production and thus uterine activity
- Indocid
3. Ca antagonists
- Ca channel blockers, which inhibit uterine activity
- Nifedipine
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What other drugs are used alongside tocolytics in preterm labour? (2)
1. Corticosteroids
- Enhance production of surfactant, thus enabling rapid expansion of the alveoli at the time of delivery and the establishment of normal respiratory function. Reduce incidence of RDS, periventricular haemorrhage and necrotizing enterocolitis.
- 2 im injections of betamethasone or dexamethasone
2. Magnesium sulphate
- Poor tocolytic effect but seems to have a neuroprotective effect
