Obstetrics Flashcards
(101 cards)
1
Q
What is Naegele’s Rule?
A
First day of LMP + 1 year - 3 months + 7 days= Due date
2
Q
What is fertilisation?
A
Fusion of the sperm nucleus with the ovum nucleus
3
Q
What is the acrosome reaction?
A
The zona pellucida cell surface glycoproteins interact with the capacitated sperm cell. Calcium enters the sperm to increase intracellular cAMP. The sperm head swells and causes enzymes to be released around the sperm head. The enzymes allow the sperm to penetrate the zona pellucida.
4
Q
Give 4 risk factors for placenta praevia
A
Previous C section High parity Previous placenta praevia Endometrial curettage after TOP/miscarriage Maternal age >40 years Multiple pregnancy Hx of uterine infection
5
Q
What is the pathophysiology of placenta praevia?
A
Placenta is attached to the lower uterine segment
Minor= low placenta but does not cover cervical os
Major= placenta lies over cervical os
The low lying placenta is more susceptible to haemorrhage and may be damaged when the fetus tries to prepare for labour.
6
Q
Describe how placenta praevia presents?
A
Painless vaginal bleeding which may increase in severity and intensity over several weeks
7
Q
How is placenta praevia diagnosed?
A
Diagnosed via US scan at 20 weeks
A low lying placenta in early pregnancy does not always become placenta praevia as when the uterus grows it can bring the placenta up
8
Q
If a patient is actively bleeding with placenta praevia what investigations should be done?
A
FBC Clotting Group and Save Crossmatch U+Es LFTs CTG
9
Q
If minor placenta praevia is found on the 20 week USS what is the management?
A
Repeat scan at 36 weeks
10
Q
If major placenta praevia is found on the 20 week USS, what is the management?
A
Repeat scan at 32 weeks
11
Q
If a patient is actively bleeding with placenta praevia, how should they be managed?
A
A-E approach
Admit
Anti-D given to Rh neg patients
Steroids if >34 weeks
12
Q
How is a woman with confirmed placenta praevia managed?
A
Elective C-section at 39 weeks
High risk of intraoperative or postpartum haemorrhage
13
Q
What is placenta accreta?
A
Placenta attaches too deeply into the uterine wall but does not extend into the myometrium
14
Q
What is placenta increta?
A
Placenta attached deep into the uterine wall and stretches into the myometrium
15
Q
What is placenta percreta?
A
Placenta penetrates through the entire wall and attaches to another organ eg. bladder
16
Q
Give 2 risk factors for placenta accreta
A
Placenta praevia
Previous C-section
17
Q
Give 3 clinical features of placenta accreta
A
Bleeding in T3
Premature delivery
Placenta doesn’t detach fully after birth leading to PPH
18
Q
How is placenta accreta managed?
A
Elective C-section +/- hysterectomy
19
Q
Give 5 predisposing factors for placental abruption
A
Placental abruption in previous pregnancy Pre-eclampsia Transverse lie of fetus Polyhydramnios Abdominal trauma Smoking Bleeding in T1 Thrombophilias Multiple pregnancy IUGR
20
Q
What is the pathophysiology of a placental abruption?
A
Part or all of the placenta separates from the uterine wall prematurely. The vessels in the basal layer of the endometrium rupture. Blood accumulates and splits the placental attachment from the basal layer. The detached placenta can no longer function.
21
Q
What is the difference between a revealed and a concealed placental abruption?
A
Revealed= bleeding tracks downwards and drains via cervix so presents with bleeding
Concealed= bleeding remains in uterus and forms a clot. No PV bleed but symptoms of shock
22
Q
Give 5 clinical features of placental abruption
A
Painful PV bleed Constant pain Dark blood Tender, hard uterus Signs of shock: tachycardia, hypotension Abnormal/absent fetal heart sounds
23
Q
What investigations can be done for a patient with placental abruption?
A
CTG FBC Clotting G+S Cross match U+Es LFTs
24
Q
How is an unstable placental abruption managed?
A
A-E assessment Admit Steroids if <34 weeks Analgesia (opiates) Anti-D to Rhesus neg Fluids
25
How is a stable placental abruption managed?
Steroids if <34 weeks
US to monitor growth
Plan delivery:
- Fetal distress= urgent C-section
- No fetal distress= IOL via amniotomy at 37 weeks
- Stillborn= Give blood, induce labour
26
Give 4 risk factors for vasa praevia
```
Placenta praevia
Multiple pregnancy
Abnormal placenta shape
IVF pregnancy
Hx of uterine surgery
Previous C-section
```
27
What is vasa praevia?
Umbilical cord attached to membranes of placenta rather than directly into it. This weakens the cord.
28
Give 2 symptoms of vasa praevia
Painless vaginal bleeding in T2/3
| Severe fetal distress- can result in organ failure and death
29
How is vasa praevia diagnosed?
Can be seen on 20 week Doppler Ultrasound
30
How is vasa praevia managed?
Elective C-section at 39 weeks
| Increased monitoring throughout pregnancy
31
What weeks are covered by Trimester 1?
0-13
32
What weeks are covered by Trimester 2?
13-27
33
What weeks are covered by Trimester 3?
27-42
34
At what age is the age of gestational viability?
24 weeks
35
Give 4 symptoms of early pregnancy
```
Missed period
Nausea and vomiting
Fatigue
Sore breasts
Polyuria
Altered taste and smell
```
36
What symptoms can be felt in early T2?
```
Thin white vaginal discharge
Backache
5-7kg weight gain
Small bump visible
Breast enlargement
```
37
When should fetal movements be felt?
18-20 weeks
38
What symptoms may be felt in late T2?
Swollen hands, face and feet
Backache
Urinary stress incontinence
39
What symptoms may be experienced in T3 of pregnancy?
```
Weight gain
Large bump
Heartburn
Swollen ankles
Short of breath
Braxton-Hicks contractions
```
40
What supplements can be started pre-conceptually to aid pregnancy?
```
Folic acid- 0.4mg/day
Vitamin D- 10 micrograms per day
Iron
Vitamin C
Calcium
```
41
What screening are diabetic mothers offered preconceptually?
Diabetic retinopathy screening
42
When does the booking visit occur?
10 weeks
43
Give 10 things discussed/done at the 10 week booking visit
Sickle cell and thalassaemia screen
Height and weight- for BMI and personalised fetal growth chart
Urine sample- check for infection/protein
Blood pressure
Bloods- FBC, U+Es
Screening for HIV, syphilis and Hepatitis B
Screening for rubella
Blood group and rhesus status
Diabetes screen
Lifestyle advice- stop smoking, good diet, gentle exercise, folate, vit D, no alcohol, antenatal classes, ask about domestic violence, leaflet about pregnancy
44
Give 5 factors which make a woman more likely to develop diabetes in pregnancy
```
High BMI (>30)
Previous gestational diabetes
Previous baby >4.5kg
Close family history of diabetes
Asian, Black or Middle Eastern
```
45
What measurement is used to date a pregnancy?
Crown-rump length
46
At how many weeks is the dating scan done?
12 weeks
47
When can a multiple pregnancy first be picked up?
12 week scan
48
What is the nuchal transleucency and what does it suggest?
Nuchal transleucency is the sonographic appearance of fluid under the skin behind the fetal neck.
The NT thickness will be increased in fetal anomalies
49
What are the 3 components of the Combined Test and what does it test for?
Nuchal translucency
PAPP-A
free beta-hCG
Calculates the risk of the baby having Down's syndrome (T21), Edward's (T18) or Patau's (T13)
50
What does a low risk combined test score mean?
< 1 in 150 chance that the baby will have having Down's syndrome (T21), Edward's (T18) or Patau's (T13)
51
What does a high risk combined test score mean?
>1 in 150 chance that the fetus will have Down's syndrome (T21), Edward's (T18) or Patau's (T13)
52
When is a quadruple test done instead of the combined test?
>14 weeks into pregnancy
| NT too hard to visualise on ultrasound
53
What 4 elements are part of the quadruple test?
AFP
hCG
Estriol
Inhibin-A
54
What does the quadruple test look for?
Down's syndrome (T21)
55
If a high risk score is given on the combined or quadruple test, what further investigations can be done to confirm the diagnosis?
Chorionic villus sampling- small sample of cells taken from the placenta using a transabdominal needle or transcervical forceps. 1% chance of miscarriage
Amniocentesis- sample of cells from amniotic fluid taken via transabdominal US guided needle. 1% risk of miscarriage.
56
When is the fetal anomaly scan carried out?
20 weeks
57
Give 5 examples of things that are looked for on the fetal anomaly scan
```
Anencephaly
Open spina bifida
Cleft lip
Serious cardiac issues
Lethal skeletal dysplasia
Patau's (T13)
Edward's (T18)
Diaphragmatic hernia
Gastroschisis
Exomphalos
Bilateral renal agenesis
Physical abnormalities- bones, heart, brain, spinal cord, face, kidneys, abdomen
```
58
What routine tests are done at every antenatal appointment?
BP and urine dip
Symphysis-fundal height done at 24 weeks
After 36 weeks assess fetal presentation + US if unsure
59
Give 6 risk factors for preeclampsia
```
Nulliparity
Maternal age >40
Maternal BMI >35
Pregnancy interval >10 years
FHx of preeclampsia
Multiple pregnancy
Chronic hypertension
Preeclampsia or HTN in previous pregnancy
Chronic kidney disease
Diabetes mellitus
Autoimmune diseases eg. SLE
```
60
What is the suggested pathophysiology of preeclampsia?
Poor placental perfusion
Remodelling of the spiral arteries is incomplete so the uteroplacental circulation is high resistance and low flow. This causes an increase in BP and oxidative stress which results in a systemic inflammatory response and endothelial cell dysfunction in the kidney resulting in proteinuria.
61
What are the 3 diagnostic criteria for preeclampsia?
Hypertension >140/90
>20 weeks gestation
++ proteinuria
62
Give 4 symptoms of preeclampsia
```
Headache
Visual disturbance
Vomiting
Epigastric pain/tenderness
Hyperreflexia
Ankle oedema
```
63
What is the BP range in mild preeclampsia?
140/90 to 149/99
64
What is the BP range for moderate preeclampsia?
150/100 to 159/109
65
What is the BP range for severe preeclampsia?
160/110 or higher
Or BP >140/90 + symptoms
66
Give 5 potential complications from preeclampsia
```
Cerebrovascular event
IUGR
Prematurity
Placental abruption
Fetal death
Eclampsia
Adult Respiratory Distress Syndrome
Pulmonary oedema
Renal failure (AKI)
Increased risk of DIC
Maternal death
HELLP syndrome
```
67
What is HELLP syndrome?
Syndrome seen in patients with preeclampsia
Haemolysis
Elevated Liver enzymes
Low platelets
68
How is HELLP syndrome treated?
Blood transfusion for anaemia
Continuous fetal monitoring
Reduce BP
Magnesium sulphate to reduce seizures
69
Apart from BP and urine dip what other investigations can be done in preeclampsia?
FBC- anaemia
U+Es- AKI
LFTs- increased ALT and AST
70
How is mild preeclampsia monitored?
BP and urine dip every week
| US every 2-4 weeks
71
When should a patient be admitted with preeclampsia?
```
Symptoms present
BP >160/110
Proteinuria >0.3g/24hr on 24hr collection
IUGR
Abnormal CTG
```
72
How is preeclampsia managed?
Anti-hypertensives:
- Labetalol
- Nifedipine
- Methyldopa
VTE prophylaxis- LMWH
Plan delivery- deliver by 36 weeks, will need maternal steroid course. Continuous CTG monitoring in vaginal birth. C-section if IUGR or abnormal CTG
Managed 3rd stage of labour- Oxytocin
73
Give 3 side effects of Labetalol and when it might be contraindicated?
S/E= leg oedema, SOB, bradycardia, chest pain, N+V, fatigue
CI= asthma, cardiac failure, heart block
74
Give 3 side effects of Nifedipine and when it might be contraindicated?
S/E= dizziness, GI disturbance, oedema, headache
CI= angina, Hx of MI, aortic stenosis, diabets
75
Give 3 side effects of Methyldopa and when it might be contraindicated?
S/E= fatigue, drowsiness, weakness, N+V
CI= heart failure, angina, kidney disease
Need to stop within 2 days of giving birth
76
What is Rhesus D red cell isoimmunisation?
Rh+ Fetal RBCs enter the mother's circulation via a 'sensitising event' or during delivery and if the mother is Rh-, maternal antibodies are formed against the fetal erythrocytes.
In subsequent pregnancies the maternal anti-D antibodies can cross the placenta and attack the fetal RBCs which results in fetal haemolytic anaemia.
77
How is red cell isoimmunisation prevented in pregnancy?
Women have maternal blood group typing and antibody screen performed at booking (10 weeks)
Repeated at 28 weeks
If mother is Rh-, fetus genotype can be assessed via father's blood or free fetal DNA in mother's blood.
If a mother is Rh- and a sensitising event occurs, she is offered Anti-D immunoglobulin. This binds to any RhD+ cells in the maternal circulation so no immune response is stimulated.
78
Give examples of 5 potential sensitising events
```
Invasive obstructive testing
Antepartum haemorrhage
Ectopic pregnancy
Fall/abdo trauma
Intrauterine death
Miscarriage
TOP
Delivery- any kind
```
79
What is the Kleihauer/FMH test?
Assesses how much fetal blood has entered the maternal circulation after a sensitising event. This can be done to work out the dose of anti-D needed.
Only done at >20 weeks
80
At <12 weeks what is the required dose of anti-D after a sensitising event?
250 IU within 72 hours
81
At 12-20 weeks what is the required dose of anti-D after a sensitising event?
250 IU within 72 hours
82
At >20 weeks what is the required dose of anti-D after a sensitising event?
500 IU within 72 hours and increase higher if the Kleihauer test suggests.
83
If a woman is Rh negative, when will she be given anti-D?
Any sensitising event in the pregnancy
28 weeks (500 IU)
34 weeks (500 IU)
Post-nataly (if baby confirmed as Rh+) (500 IU)
84
How is fetal haemolytic anaemia investigated prenatally?
Doppler US of the peak velocity of the fetal middle cerebral artery
Fetal blood sampling under US guidance
Severe anaemia= fetal hydrops, excessive fetal fluid
85
How is fetal haemolytic anaemia treated prenatally?
Intrauterine blood transfusion to fetus
86
What is the most common virus transmitted to the fetus in pregnancy?
Cytomegalovirus (CMV)
87
Give 4 effects of Cytomegalovirus (CMV) on the fetus?
```
IUGR
Hepatosplenomegaly
Thrombocytopenic purpura
Jaundice
Microcephaly
Pneumonia
Sensorineural hearing loss
Visual impairment
Risk of DIC
```
88
How is Cytomegalovirus (CMV) diagnosed in pregnancy?
Mother: Viral serology for CMV specific IgM and IgG
Fetus: US scan at 20 weeks, amniocentesis >21 weeks to confirm
89
How is Cytomegalovirus (CMV) in pregnancy managed?
Offer TOP
| Serial US scanning to look for abnormalities
90
How does rubella in pregnancy present in the mother, neonate and older child?
Mother= asymptomatic, fine maculopapular rash, coryza, malaise, lymphadenopathy, headache
Neonate= sensorineural deafness, PDA, pulmonary stenosis, VSD, retinopathy, cataracts, microcephaly
Infant= diabetes, GH abnormalities, thyroiditis, behavioural disorders, learning difficulties
91
How is a rubella infection in pregnancy managed?
Gestational age at exposure to rubella infection:
<12 weeks= TOP
12-20 weeks= amniocentesis diagnosis, TOP or US surveillance
>20 weeks= no action required
92
What are the maternal symptoms of Varicella Zoster infection in pregnancy?
Pruritic maculopapular rash
Fever
Malaise
93
What are the symptoms of Varicella Zoster infection in a fetus <20 weeks old?
Dermatomal skin scarring
Eye defects= optic atrophy, cataracts
Hypoplasia of limbs
Neurological abnormalities= microcephaly, seizures, Horner's, spinal cord atrophy
94
How is a Varicella Zoster infection in pregnancy managed?
Varicella zoster immunoglobulin within 10 days of potential infection if not already immune
If suffering from chickenpox= Aciclovir
95
What are the effects to the fetus in maternal Parvovirus B19 in pregnancy?
Fetal hydrops= virus replicates in liver and bone marrow causing severe anaemia which results in cardiac failure and portal hypertension and hypoprolactinaemia
96
How is Parvovirus in pregnancy treated?
Serial US and dopplers every 1-2 weeks until 30 weeks. In a tertiary center an intrauterine erythrocyte transfusion can be done
97
Give 4 risk factors for Group B strep infection in neonates
```
Prematurity <37 weeks
GBS in previous baby
Rupture of membranes >24hrs before delivery
Pyrexia during labour
Positive GBS in mother
```
98
What 3 infections does Group B Streptococcus cause in the mother?
UTI
Chorioamnionitis
Endometritis
99
How does a Group B Streptococcus infection present in a neonate?
Sepsis
| Pyrexial, cyanosis, floppy, poor breathing, poor feeding
100
How is Group B Streptococcus diagnosed in pregnancy?
High vaginal swab
Anal awab
Urine testing if UTI symptoms
Not routinely screened for in the UK
101
How is Group B Streptococcus colonisation managed in pregnancy?
If any risk factors are present, maternal high dose penicillins given throughout vaginal labour.
