Obstetrics Flashcards

(141 cards)

1
Q

What is the most common site for ectopic pregnancies?

A

Ampulla of the fallopian tube

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2
Q

What are risk factors for ectopic pregnancy?

A

Previous ectopic pregnancy
Previous pelvic inflammatory disease
Previous surgery to fallopian tubes
IUD
Older age (>35)
Smoking
IVF
Being under 18 at first sexual intercourse
Black race

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3
Q

What are classic presenting features of an ectopic pregnancy?

A

Presents at 6-8 weeks
Missed period
Constant pain in right or left iliac fossa
Vaginal bleeding
Lower abdominal or pelvic tenderness
Cervical motion tenderness
Dizziness/syncope (blood loss)
Shoulder tip pain (peritonitis)

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4
Q

What is the management for ectopic pregnancy?

A

No pain, no visible heartbeat, unruptured, <35mm, HCG < 1500 IU/l = Expectant management

HCG<5000IU/l + combined absense of intrauterine pregnancy = methotrexate

Pain, >35mm, visible heartbeat, HCG > 5000IU/l = surgery –> laparoscopic salpingectomy/salpingotomy

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5
Q

What is the investigation of choice for diagnosing a miscarriage?

A

Transvaginal US

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6
Q

What is the management of miscarriage?

A

Less than 6 weeks = Expectant if no pain or signs of ectopic
More than 6 weeks:
Referral to early pregnancy unit
Expectant
Medical –> Misoprostol (softens the cervix and stimulates uterine contractions)
Surgical –> Vacuum aspiration

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7
Q

What is a threatened miscarriage?

A

Patient presents with vaginal bleeding but the pregnancy is still viable
Cervical os is closed

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8
Q

What is a missed miscarriage?

A

A gestational sac before 20 weeks that contains a non-viable fetus, without the symptoms of expulsion
May have light vaginal bleeding but no flooding or pain
Cervical os close

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9
Q

What is an inevitable miscarriage?

A

Heavy vaginal bleed with an open cervical os
Nothing can be done to prevent miscarriage

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10
Q

What is an incomplete miscarriage?

A

Not all products of conception have been expelled
Pain and bleeding
Open cervical os

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11
Q

What is a complete miscarriage?

A

Full miscarriage with no remaining products of conception

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12
Q

What is the cause of hyperemesis gravidarum?

A

In pregnancy, the placenta produces human chorionic gonadotrophin (HCG), which is responsible for nausea and vomiting
Higher levels of HCG (molar pregnancies, multiple pregnancies) lead to more severe symptoms

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13
Q

What is the medical management of hyperemesis gravidarum?

A

1st line = prochlorperazine
2nd line = cyclizine
3rd line = ondansetron
4th line = metoclopramide

Ranitidine/omeprazole if acid reflux is a problem

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14
Q

What is a hydatidiform mole/molar pregnancy?

A

A tumour that grows like a pregnancy inside the uterus.
Complete mole = two sperm cells fertilise an empty ovum, and start to divide but do not form any foetal material
Partial mole = two sperm cells fertilise a normal ovum at the same time, now having 3 sets of chromosomes, and divides, may form some foetal material

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15
Q

What factors indicate molar pregnancy instead of normal pregnancy?

A

More severe morning sickness
Vaginal bleeding
Increased uterine enlargement
Abnormally high HCG
Thyrotoxicosis

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16
Q

What is the management of a molar pregnancy?

A

Evacuation of the uterus
Send products for histological examination
Follow up and check for metastases

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17
Q

What is the classic triad of pre-eclampsia features?

A

Hypertension (pregnancy-induced)
Proteinuria
Oedema

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18
Q

What are the risk factors for pre-eclampsia?

A

High risk:
Pre-existing hypertension
Previous hypertension in pregnancy
Existing autoimmune condition eg. SLE
Diabetes
Chronic kidney disease

Moderate risk:
Older than 40
BMI>35
More than 10 years since last pregnancy
First pregnancy
Multiple pregnancy
Family history of pre-eclampsia

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19
Q

What are the symptoms of pre-eclampsia?

A

Headache
Visual disturbance
Nausea and vomiting
Upper abdominal or epigastric pain
Oedema
Reduced urine output
Brisk reflexes

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20
Q

What is the management of pre-eclampsia?

A

Prophylactic aspirin from 12 weeks until birth if 1 high-risk factor or more than 1 moderate-risk factors
Monitoring –> BP, symptoms, urine dipstick
Aim for BP below 135/85
Labetolol (first line medication)
Nifedipine (second line)
Methyldopa (third line)

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21
Q

What is eclampsia?

A

Seizures associated with pre-eclampsia

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22
Q

What is the management of eclampsia?

A

IV magnesium sulphate

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23
Q

What does HELLP stand for?

A

Haemolysis
Elevated Liver enzymes
Low Platelets

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24
Q

What is HELLP syndrome?

A

A combination of features that occur as a complication of pre-eclampsia and eclampsia

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25
What are the risk factors for gestational diabetes?
Previous gestational diabetes Previous macrosomic baby (>4.5kg) BMI>30 Black Caribbean, Middle Eastern or South Asian ethnicity Family history of diabetes (first degree relative)
26
What presenting features suggest gestational diabetes?
Large-for-date foetus Polyhydramnios Glucose on urine dipstick
27
What is the initial investigation of choice for gestational diabetes?
Oral glucose tolerance test (OGTT) Performed in the morning after fasting Patient then drinks 75g of glucose in solution Normal glucose before = <5.6mmol/l Normal glucose after 2 hours = <7.8mmol/l (5-6-7-8)
28
What is the management of gestational diabetes?
Fasting glucose <7mmol/l = diet and exercise for 1-2 weeks, then metformin, then insulin Fasting glucose >7mmol/l OR >6mmol/l with macrosomia = Start insulin +/- metformin
29
What is the cause of anaemia in pregnancy?
In pregnancy, the total blood volume increases This means that the Hb concentration is decreased
30
What is the management of anaemia in pregnancy?
Iron replacement B12 replacement --> IM hydroxocobalamin/oral cyanocobalamin Folic acid
31
What are the risk factors for VTE in pregnancy?
Smoking Parity >=3 Age>35 BMI>30 Reduced mobility Multiple pregnancy Pre-eclampsia Immobility Family history IVF pregnancy
32
What VTE prophylaxis is given in pregnancy?
Low molecular weight heparin --> asap in very-high risk (4 or more risk factors), at 28 weeks in high risk (3 risk factors)
33
What is the presentation of VTE in pregnancy?
Unilateral calf or leg swelling Dilated superficial veins Tenderness to the calf Oedema Colour changes to the leg Signs of PE --> SoB, chest pain, cough etc
34
Why is VTE risk increased in pregnancy?
Hyper-coagulable state
35
What is placenta praevia?
When the placenta lies over the internal cervical os
36
What is the definition of low-lying placenta?
When the placenta is within 20mm of the internal cervical os
37
What are the grades of placenta praevia?
Grade 1 (minor) = Placenta is in the lower uterus but not reaching the internal cervical os Grade 2 (marginal) = Placenta is reaching, but not covering, the internal os Grade 3 (partial) = Placenta is partially covering the internal os Grade 4 (complete) = Placenta is completely covering the internal os
38
What are the risk factors for placenta praevia?
Previous C section Previous placenta praevia Older maternal age Maternal smoking Structural uterine abnormality (eg. fibroids) IVF
39
How is a diagnosis of placenta praevia made?
20 week anomaly scan identifies the position of the placenta Many women are asymptomatic May present with antepartum haemorrhage
40
What is the management of placenta praevia?
Transvaginal US for monitoring Corticosteroids given between 34 and 35+6 weeks to promote fetal lung maturation Planned C section at 36-37 weeks Emergency C-section if labour is premature or any bleeding
41
What is placenta accreta?
When the placenta implants deeper, through and past the endometrium, making it difficult to separate the placenta after delivery
42
What are the risk factors for placenta accreta?
Previous placenta accreta Previous miscarriage Previous C section Multigravida Increased maternal age Low-lying placenta or placenta praevia
43
What is the management of placenta accreva?
Planned delivery between 35 and 36+6 weeks Recommended hysterectomy Uterine preserving surgery Expectant management --> risks of bleeding and infection
44
What is vasa praevia?
Where fetal vessels (two umbilical arteries and one umbilical vein) are in the fetal membranes and travel across the internal cervical os, outside the protection of the placenta or umbilical cord
45
What are the risk factors for vasa praevia?
Low lying placenta IVF Multiple pregnancy
46
What is the management of vasa praevia?
Corticosteroids to mature the fetal lungs Planned C-section at 34-36 weeks Emergency C-section if antepartum haemorrhage occurs
47
What is placental abruption?
When the placenta comes away from the uterine wall during pregnancy
48
What are the risk factors for placental abruption?
Previous placental abruption Pre-eclampsia Trauma Multiple pregnancy Multigravida Increased maternal age Smoking Cocaine/amphetamine use
49
What is the presentation of placental abruption?
Sudden onset, continuous, severe abdominal pain Vaginal bleeding Shock (hypotension and tachycardia) Abnormalities on CTG showing fetal distress Woody abdomen on palpation
50
What is the management for placental abruption?
Obstetric emergency Steroids to mature fetal lungs Emergency C-section if mother is unstable or fetus is distressed
51
What is the definition of a stillbirth?
The birth of a dead fetus after 24 weeks gestation
52
What is cord prolapse?
When the umbilical cord descends below the presenting part of the fetus into the vagina after rupture of the fetal membranes Significant risk of compression causing fetal hypoxia
53
What is the management of a prolapsed cord?
Move patient onto all fours whilst preparing for emergency C-section Push presenting part back into the uterus to prevent compression Fill bladder to elevate presenting part Emergency C-section
54
What are the degrees of perineal tears?
First degree = Superficial damage with no muscle involvement Second degree = Injury to perineal muscle but not involving anal sphincter Third degree = Injury to perineum involving the anal sphincter Fourth degree = Injury to perineum involving the anal sphincter and rectal mucosa
55
What is the management of perineal tears?
First degree = Does not require repair Second degree = Suturing on the ward Third or fourth degree = Repair in theatre
56
What are the risk factors for perineal tears?
Primigravida Large babies Precipitant labour Shoulder dystocia Forceps delivery
57
What is the timeframe of a primary vs secondary postpartum haemorrhage?
Primary = within 24 hours Secondary = 24 hours to 12 weeks
58
What volume of blood loss indicates postpartum haemorrhage?
>500ml
59
What are the causes of postpartum haemorrhage?
Tone --> uterine atony (majority of cases) Trauma --> eg perineal tear Tissue --> retained placenta Thrombin --> bleeding disorder
60
What are the risk factors for primary postpartum haemorrhage?
Previous PPH Prolonged labour Pre-eclampsia Increased maternal age Polyhydramnios Emergency C-section Placenta praevia/accreta Macrosomia
61
What is the management of a postpartum haemorrhage?
Mechanical --> Rub the uterus to stimulate contractions, catheterisation Medical --> IV oxytocin, IV or IM ergometrine, IM carboprost (unless asthmatic), misoprostol Surgical --> Intrauterine balloon tamponade, ligation of uterine arteries etc
62
What are the most likely causes of secondary postpartum haemorrhage?
Retained products of conception Infection
63
What is the management of chickenpox in a pregnant mother who is unsure if they have has chickenpox before?
Aciclovir
64
What screening tests are done for Down's syndrome?
Combined test done 11-13+6 weeks: Nuchal translucency --> Thickened in Down's Serum B-HCG --> Increased in Down's PAPP-A --> Decreased in Down's Triple test done at 14-20 weeks: Beta-HCG --> Increased in Down's Alpha-fetoprotein (AFP) --> Lower in Down's Serum oestriol --> Lower in Down's Quadruple test done at 14-20 weeks: Same as triple test Also includes Inhibin-A --> Increased in Down's
65
What is the first stage of labour?
From the onset of labour until the cervix is fully dilated at 10cm Involves cervical dilation and effacement Mucus plug falls out
66
What are the three phases of the first stage of labour?
Latent phase = 0-3cm dilation at 0.5cm per hour with irregular contractions Active phase = 3-7cm dilation at 1cm per hour with regular contractions Transition phase = 7-10cm dilation at 1cm per hour with strong, regular contractions
67
What is the second stage of labour?
From 10cm dilation to delivery of the baby
68
What is the third stage of labour?
From delivery of the baby to delivery of the placenta
69
What factors affect the success of the second stage of labour?
Power --> Strength of uterine contractions Passenger --> Size (size of head at largest point), Attitude (posture eg. how the back is rounded), Lie (position of fetus relative to the mother), Presentation (part of fetus closest to cervix) Passage --> Size and shape of the passageway, particularly the pelvis
70
What are the seven cardinal movements of labour?
Engagement Descent Flexion Internal rotation Extension Restitution and external rotation Expulsion
71
What gestation is classed as premature?
Before 37 weeks
72
What can be given prophylactically to prevent preterm labour?
Vaginal progesterone --> Decreases activity of myometrium and prevents cervical remodelling
73
What is the management of preterm prelabour rupture of membranes?
Prophylactic antibiotics (erythromycin) for 10 days or until labour is established Induction of labour may be offered
74
What is the management of preterm labour with intact membranes?
Fetal monitoring Tocolysis (medication to stop uterine contractions) with nifedipine (a CCB that suppresses labour) Corticosteroids (promotes fetal lung maturation) IV magnesium sulphate (protects baby's brain)
75
What are the indications for induction of labour?
When patients go over due date Prelabour rupture of membranes Pre-eclampsia Obstetric cholestasis Existing diabetes Intrauterine fetal death
76
What is the Bishop score?
Scoring system to determine whether or not to induce labour Scored on a scale of 0-13 Score of 8 or more indicates a successful induction of labour Score of less than 8 suggests cervical ripening is required Five factors assessed: Fetal station (0-3) Cervical position (0-2) Cervical dilation (0-3) Cervical effacement (0-3) Cervical consistency (0-2)
77
What are possible methods of induction of labour?
Membrane sweep Vaginal prostaglandins Cervical ripening balloon --> inserted into cervix and gently inflates, dilating the cervix Artificial rupture of membranes with oxytocin (only if vaginal prostaglandins are contraindicated or have failed) Oral mifepristone + misoprostol --> if intrauterine fetal death
78
What is a complication of induction of labour with vaginal prostaglandins?
Uterine hyperstimulation
79
What is the management of uterine hyperstimulation?
Removing the vaginal prostaglandins or stopping oxytocin infusion Tocolysis with terbutaline
80
What does cardiotocography measure?
Fetal heart rate --> sensor placed above fetal heart Contractions of the uterus --> sensor placed near the fundus of the uterus
81
What are the indications for continuous CTG monitoring?
Sepsis Maternal tachycardia Significant meconium Pre-eclampsia Fresh antepartum haemorrhage Delay in labour Use of oxytocin Disproportionate maternal pain
82
What are the 5 features to look for on a CTG?
Contractions = Number per 10 minutes Baseline fetal heart rate Variability = How the fetal heart rate varies about the baseline Accelerations of fetal HR --> generally good sign Decelerations of fetal HR --> more concerning if after uterine contractions or for prolonged time
83
What is the rule of 3s for fetal bradycardia?
3 minutes = call for help 6 minutes = move to theatre 9 minutes = prepare for delivery 12 minutes = deliver the baby (by 15 minutes)
84
What is oxytocin used for in labour?
Induction Progression Improve frequency and strength of contractions Prevent of treat PPH
85
What is ergometrine used for in labour?
Stimulates smooth muscle contraction Used for delivery of placenta Reduce PPH Only used postpartum
86
What are prostaglandins used for in pregnancy?
Have hormonal effects locally Prostaglandin E2 used in induction of labour
87
What is recorded on a partogram?
Cervical dilation Descent of fetal head Maternal pulse, BP, temp and urine output Fetal HR Frequency of contractions Membrane status Any drugs or fluids being given
88
What pain relief is used in labour?
Simple analgesia --> Paracetamol, codeine. NSAIDs are avoided Gas and Air (Entonox) IM pethidine or diamorphine Epidural
89
What is shoulder dystocia?
When the anterior shoulder of the baby becomes stuck behind the pubic symphysis
90
What is the presentation of shoulder dystocia?
Difficulty delivering the face and head Face remains downwards after delivery of the head Turtle-neck sign = Where the head is delivered but retracts back onto the vagina
91
What is the management of shoulder dystocia?
Obstetric emergency Episiotomy McRoberts manoeuvre = Bringing knees up to abdomen to lift the pubic symphysis out of the way Pressure to anterior shoulder by pressing on the suprapubic abdomen
92
What are the indications for an instrumental delivery?
Failure to progress Fetal distress Maternal exhaustion Control the head in various fetal positions Increased risk if epidural in place as less pushing power
93
What are the indications for an elective C-section?
Previous C-section Symptomatic after previous significant perineal tear Placenta praevia Vase praevia Breech presentation Multiple pregnancy Uncontrolled HIV Cervical cancer
94
What are the different categories of C-section?
Category 1 = Immediate threat to life of mother/baby --> Delivery in 30 minutes Category 2 = Not imminent threat to life but required urgently due to compromise of mother or baby --> Delivery in 75 minutes Category 3 = Delivery in required, but mother and baby are stable Category 4 = Elective
95
What are the risk factors for a uterine rupture?
Previous C-section Previous uterine surgery Increased BMI High parity Increased age Induction of labour
96
What is the presentation of a uterine rupture?
Abdominal pain Vaginal bleeding Ceasing of uterine contractions Hypotension Tachycardia Collapse
97
What is the management of uterine rupture?
Emergency C-section Repair or remove the uterus
98
What are the baby blues?
A mental illness affecting around 50% of mothers in the first week or so after birth
99
What are the precipitating factors for baby blues?
Significant hormonal changes Recovery from birth Fatigue and sleep deprivation Responsibility and pressure Changes in environment
100
What are the symptoms of baby blues?
Mood swings Low mood Anxiety Irritability Tearfulness
101
What is puerperal psychosis?
Rare but severe illness starting 2-3 weeks after delivery
102
What are the symptoms of puerperal psychosis?
Delusions Hallucinations Depression Mania Confusion Thought disorder
103
What is an amniotic fluid embolism?
When fetal cells/amniotic fluid enter the mother's bloodstream and stimulate a reaction
104
What are the presentations of an amniotic fluid embolism?
Occur in labour or in the immediate post-partum Chills/shivering/sweating Anxiety Coughing Cyanosis Hypotension Tachycardia Bronchospasms Myocardial infarction
105
What is the management of an amniotic fluid embolism?
ICU Supportive Monitor BP and HR
106
What is the presentation of obstetric cholestasis?
Itching --> particularly palms and soles of feet Fatigue Dark urine Pale, greasy stools Jaundice NO RASH
107
What is gastroschisis?
Congenital defect in the anterior abdominal wall lateral to the umbilical cord, allowing the intestines and other abdominal organs to exit the body
108
What is the management of gastroschisis?
Vaginal delivery may be attempted Newborns should go to theatre within 4 hours of delivery
109
What is exomphalos/omphalocoele?
Where the abdominal contents protrude through the anterior abdominal wall but are covered in amniotic sac formed by the amniotic membrane and peritoneum
110
What is the management of exomphalos?
C-section to reduce risk of sac rupturing Repair often difficult due to high intra-abdominal pressure so wait until infant has grown and contents can be put back inside and damage repaired
111
At what gestation should a booking visit be done?
8-12 weeks
112
At what gestation should the early scan to confirm dates be done?
10-13+6 weeks
113
At what gestation can Down's syndrome screening, including nuchal scan, be done?
11-13+6 weeks
114
At what week is an anomaly scan done?
18-20+6 weeks
115
At what gestation is external cephalic version offered if indicated?
36 weeks
116
What physiological changes to blood pressure happen in pregnancy?
Falls in the first trimester until 20-24 weeks and the increases to the pre-pregnancy levels by term
117
What are the 2 phases of the menstrual cycle?
Follicular phase (first 14 days) Luteal phase (last 14 days)
118
What is the role of FSH at the start of the menstrual cycle?
Stimulate development of the secondary follicles
119
What is the role of granulosa cells in the follicular phase of the menstrual cycle?
Surrounds the follicles Secretes oestradiol (naturally occurring oestrogen)
120
What is the effect of oestradiol on the pituitary gland?
Negative feedback Reduces the levels of LH and FSH
121
What is the effect of rising oestrogen on the cervix?
Causes the cervical mucus to be more permeable, allowing sperm to penetrate the cervix
122
Which hormone causes the follicle to release the ovum?
LH
123
At what date does ovulation occur?
14 days before the end of the cycle (Day 14 of 28-day cycle, Day 16 of 30-day cycle etc)
124
What happens to the follicle after releasing the ovum?
Collapses and becomes the corpus luteum, which secretes high levels of progesterone
125
What is the role of progesterone in the luteal phase?
Maintain the endometrial lining and thickens the cervical mucus, making it no longer penetrable
126
What maintains the corpus luteum after fertilisation?
The syncytiotrophoblast of the embryo secretes HCG, which maintains the corpus luteum and continues the secretion of progesterone
127
What happens to the corpus luteum if there is no fertilisation?
It degenerates and stops producing oestrogen and progesterone This causes the endometrium to break down and menstruation to occur
128
On what day of the menstrual cycle does menstruation occur?
Day 1
129
What is the effect of no fertilisation on LH and FSH?
No fertilisation causes the corpus luteum to break down, stopping the secretion of oestrogen and progesterone This stops the negative feedback of oestrogen and progesterone on the hypothalamus and pituitary gland, allowing FSH and LH to begin to rise The cycle restarts
130
What are the physiological cardiovascular changes in pregnancy?
Increased blood volume Increased plasma volume Increased cardiac output --> increased stroke volume and heart rate Decreased peripheral vascular resistance Decreased blood pressure in early and middle trimesters, returning to normal by term Varicose veins Peripheral vasodilation (flushing and hot sweats)
131
What are the physiological respiratory changes in pregnancy?
Tidal volume and respiratory rate increase in later pregnancy to meet increased oxygen demand
132
What are the physiological renal changes in pregnancy?
Increased renal blood flow Increased GFR Increased aldosterone Increased protein excretion
133
What are the physiological haematology changes in pregnancy?
Increased RBC production Higher iron, folate and B12 requirements Lower concentration of RBC due to higher plasma volume increase --> anaemia
134
What are the 3 stages of postpartum thyroiditis?
Thyrotoxicosis Hypothyroidism Normal thyroid function, but high recurrence rate in future pregnancies
135
What is the management of the thyrotoxicosis stage of postpartum thyroiditis?
Propranolol until symptoms resolve in around 1 year Not usually treated with anti-thyroid drugs
136
What is the management of the hypothyroid phase of postpartum thyroiditis?
Thyroxine
137
What is oligohydramnios?
Deficiency of amniotic fluid in pregnancy
138
What are the causes of oligohydramnios?
Premature rupture of membranes Fetal renal problems/agenesis Intrauterine growth restriction Post-term gestation Pre-eclampsia
139
How can fetal growth be assessed?
Measure length of femur on US Measure fetal abdominal circumference using US Measure size of uterus on abdominal examination Palpate the fetal head on examination Measure length of femur on US
140
What antibiotics are safe to use at any stage of pregnancy?
Cephalosporins
141
What are risk factors for intrauterine growth restriction?
Maternal age under 16 or over 35 Low BMI >75kg Interpregnancy interval of less than 6 months or over 120 months Trisomy 18 Pre-eclampsia