Obstetrics Flashcards
What tests are carried out at the booking appointment?
BBV screen Thalassaemia and sickle cell screen Group + save, rhesus status Hb and platelets BP + urine dip
What is the standard DS screening?
When is it done?
Combined test
Dating scan 12w: Nuchal translucency, B-hcg, PAPP-A, maternal age
If high risk: Invasive testing 11-15w
If >14w: quadruple test
Bloods: B-hcg, AFP, inhibin a, oestradiol
When is anti-D offered to rhesus negative women?
28w
34w
At birth
Any potential sensitising events
When is the OGTT performed for high risk women?
28w
What is measured at all routine antenatal appointments?
SFH
BP + urine
Safest anti-epileptic in pregnancy
Lamotrigine
Drugs to use in UTI in pregnancy
Nitrofurantoin 5d T1-2
Trimethoprim 5d T3
How should Grave’s disease be managed in pregnancy?
PTU in T1, then carbimazole
What is the target glucose range in pregnancy?
Fasting: 5-7
HbA1c: <48
How does pregnancy affect diabetes?
- Increased insulin requirement
- Higher risk of diabetic complications
- Higher risk of hypos
How does diabetes affect pregnancy?
Increased risk miscarriage, stillbirth, premature labour
Increased risk pre-eclampsia, PROM, cord prolapse, PPH
Increased risk macrosomia, polyhydramnios, shoulder distocia
Increased risk neonatal hypos, neonatal jaundice, congenital abnormality
Pre-conception advice in diabetics
Control weight
At least 3 months good sugar control: HbA1c <48
Ensure medication appropriate: metformin, insulin
5mg folic acid
Antenatal precautions in diabetes
75mg aspirin OD to reduce risk of pre-eclampsia
Glucose monitoring at least 4 times daily
4 weekly growth scans from 28 weeks
2 weekly midwife review
Obstetric-led care
Intrapartum care in diabetes:
If complicated pregnancy, offer elective delivery <40+6
If macrosomia/est weight >4.5kg offer CS
If poor glucose control, insulin sliding scale during labour
Feed within first 30m to prevent neonatal hypoglycaemia
-> check neonatal BM 2-4 hourly, ensure >2mmol/L
Revert back to pre-preg doses postpartum and review
What are the risk factors for gestational diabetes?
High BMI
Previous baby > 4.5kg
Personal history of GDM or 1st degree family history
Ethnicity: AC or south Asian
What are the complications associated with GDM?
Increased risk miscarriage, stillbirth, premature labour
Increased risk pre-eclampsia, PROM, cord prolapse, PPH
Increased risk macrosomia, polyhydramnios, shoulder distocia
Increased risk neonatal hypos, neonatal jaundice, congenital abnormality
Increased risk maternal T2DM
How is GDM diagnosed?
Risk factor screening at booking appointment
HbA1c at booking to identify any undiagnosed T2DM
High risk patients go for OGTT at 28w
-> Normal fasting <5.1, 2hour <7.8
If impaired, diagnosis made.
What are target BMs in GDM?
Fasting <5.3
Post-meal <7.8
What antenatal precautions are taken in GDM?
Aspirin 75mg
LMWH antenatally and up to 6/52 postnatally
2 weekly review by team
4 weekly growth scans from 28w
What is post-natal management of GDM?
First feed <30m to avoid neonatal hypo- ensure glucose >2
Stop all medication
6-12w review with GP to check for development of T2DM and need for ongoing treatment
What dose of vitamin D should be given to those at risk of deficiency?
10 micrograms daily
What can be given to help with sickness in pregnancy?
Antihistamines - cyclizine 50mg 8 hourly first line
Ensure to check ketones and observations
May need admitting for IV fluid replacement and prevention of dehydration
What is target BP in pregnancy?
<135/85mmHg
What is used in pregnancy for BP management?
What else is given to prevent complications?
Labetalol
Nifedipine
Methyldopa
75mg aspirin OD to reduce risk of pre-eclampsia
How is hypertension managed postnatally?
Stop medication/revert to pre-pregnancy doses
BP measurement on day 1, 2 and 3-5 post-delivery
Aim for <140/90
Stop methyldopa by day 2 to reduce risk of post-natal depression
What are the risk factors for pre-eclampsia?
Maternal age >40 Maternal BMI >30 Nulliparity / multiple pregnancy Maternal smoking Maternal diabetes, GDM, HTN, CVD, renal disease, autoimmune disease, PCOS Personal/family history pre-eclampsia High altitude
What are the symptoms of pre-eclampsia?
REDUCED FOETAL MOVEMENTS Headache Visual disturbance Upper abdominal pain Swelling of hands/feet/face, shortness of breath Nausea +/- vomiting Oliguria Seizures
What investigations should be done in suspected pre-eclampsia?
Maternal BP (>140/90)
Urine dip: proteinuria
Maternal bloods: FBC, U&E, LFT, clotting
USS
Umbilical artery doppler- ensure forward flow
How is pre-eclampsia managed?
- IV labetalol
- IV mag sulphate to prevent seizures
- If unstable- CS is definitive management
- > Steroids for lung development if pre-term - If stable on BP control and proteinuria stops, can discharge with close monitoring
What is HELLP syndrome?
Haemolytic anaemia
Elevated liver enzymes
Low platelets
- syndrome associated with pre-eclampsia
What are the symptoms of HELLP syndrome?
Pre-Eclampsia symptoms, especially RUQ pain
Nausea and vomiting
BRISK tendon reflexes
Oedema
How should HELLP syndrome be investigated?
FBC, LFT, Clotting
Urine: proteinuria
USS
How should suspected and confirmed HELLP syndrome be managed?
Suspected:
IV magnesium sulphate
IV dexamethasone
Labetalol/nifedipine/methyldopa
Confirmed:
Emergency C section
Continue the above
May need blood products/platelets and anti-D
What is the definition of SGA?
Foetus born with a birthweight <10th percentile
What is the definition of FGR?
What are the two types?
Failure of a foetus to reach its predetermined growth potential due to pathology
Symmetrical: proportionally small. Usually due to an early insult such as chromosomal abnormality, IU infection or maternal drug use
Asymmetrical: blood diversion to brain and heart, depletion of abdominal fat stores
Due to later insult such as pre-eclampsia, maternal smoking + HTN
What are the risk factors for FGR?
MAJOR:
Maternal age >40, maternal BMI >30, maternal smoking >11, cocaine use, personal/1st degree history FGR, pre-eclampsia, chronic HTN, maternal renal/CVD/vascular disease, heavy PV bleeding
MINOR:
Maternal age >35, Maternal BMI <20, maternal smoking <11, previous pre-eclampsia, nulliparity, IVF pregnancy
How is FGR detected?
Screening for RFs at booking appt
- > if 1+ major - serial growth scans from 28w
- > if 3+ minor, umbilical artery doppler at 20w and if abnormal then same as ^
If no risk factors, SFH is measured and plotted at each appointment- if <10th percentile or loss of trajectory, serial growth scans and umbilical artery dopplers
In FGR, what is an immediate indication for delivery of the baby?
Retrograde end-diastolic flow on umbilical artery doppler
How is FGR managed?
If <32w: extensive investigation for syndromic conditions which may be the cause. Steroids for lung maturation and close monitoring of foetus and dopplers.
If >32w: close monitoring, steroids and delivery if any foetal distress/compromise
What do the parts of the APGAR score stand for?
Appearance Pulse Grimace Activity Respiration
Each scored out of 2, max score 10
In PROM, what is the earliest gestation that a pregnancy should be induced?
34 weeks
What are the two methods for induction of labour?
- Membrane sweep
50% efficacy - Vaginal prostaglandins (PGE2)
Softens the cervix
One dose given, another 6 hours later if no labour
What is the contraindication to induction with PGE2?
Risk of uterine hyperstimulation
What is given during labour to encourage the third stage?
Oxytocin (Syntocinon) infusion
What causes foetal distress?
Compression of the head -> vagal stimulation and bradycardia
Reduction in oxygen supply e.g. placental insufficiency, cord compression/prolapse, maternal hypoxia
What are variable decelerations usually a sign of?
Cord compression
What is considered a normal foetal heart rate?
100-160bpm
What are the complications associated with macrosomia?
Shoulder dystocia, need for operative delivery
Damage to genital tract during delivery
Increased risk of uterine rupture and PPH
Birth injury to the foetus
Foetal hypoglycaemia, childhood diabetes
What are the risk factors for macrosomia?
Impaired glucose tolerance- DM, GDM
Maternal obesity
Overdue
Increased maternal age
What causes polyhydramnios?
Increased foetal urine production: diabetes, twin-twin transfusion
Impaired ability to swallow/absorb fluid: GI deformity, muscular or neurological problem
What are the main complications of polyhydramnios?
Pre-term delivery due to uterine stretch
PROM
Maternal breathing difficulties
What causes oligohydramnios?
Reduced foetal urine production: FGR, renal failure, post-dates
Obstruction to foetal urine output: posterior urethral valves
What are the complications of oligohydramnios?
PROM and premature labour
Limb abnormalities if prolonged
FGR, lung hypoplasia
How would you investigate somebody with oligohydramnios?
USS + doppler for FHR
Speculum examination to look for ruptured membranes
How should SROM be managed?
FBC, CRP
Vaginal swabs
If >34 weeks: induce labour
<34w: prophylactic erythromycin, monitor for infection, daily CTG and induction 34-36w
What manœuvres are indicated in shoulder dystocia?
Woods manoeuvre: Lie on back with hips hyper flexed and thighs out, suprapubic pressure
Screw manoeuvre: try rolling onto all 4s
Cesarean section ASAP
What is the similarity/difference between a threatened and an inevitable miscarriage?
Both present with bleeding and pain
Both have all the tissue on USS and may even have heart activity
THREATENED: cervix is closed
INEVITABLE: cervix is open, meaning miscarriage is imminent
What are the differences between an incomplete and complete miscarriage?
Incomplete still have pain and bleeding, this has stopped by the time it is complete
Cervix open in incomplete, closed in complete
No foetal tissues in the womb and thin endometrium in complete, some tissue remains in incomplete
What are the features of missed miscarriage/early foetal demise?
Bleeding and pain
Cervix closed
Foetal pole present but no heart activity
What should be given to all patients with threatened/confirmed miscarriage?
Anti-D if over 12w and rhesus negative.
What are the options for miscarriage management?
- Expectant
Appropriate if clinically stable and not bleeding heavily.
TVUSS should be repeated after 2 weeks to ensure no retained products -> surgical removal - Medical
If patient is stable, no signs of infection
Oral/vaginal misoprostol given
Mifepristone often given 24-48 hours before to prime the cervix
Bleeding may continue for <3 weeks - Surgical
TV suction of products under general anaesthetic
Indicated if: excessive bleeding, maternal instability, infection, patient choice
What are the complications of surgical management of miscarriage?
Infection, haemorrhage, retained products
Damage to GU tract, cervical tears, intra-abdominal trauma
IU adhesions
How should you assess a patient with suspected miscarriage?
Full obstetric and gynaecological history
Vital signs
Abdominal and vaginal examination - speculum to see if cervix is closed or open
TV USS
Bloods: FBC, B-HCG, group and save
Check rhesus status - > anti-D if appropriate
What are the risk factors for ectopic pregnancy?
Previous ectopic, PID, tubal surgery, endometriosis
Assisted conception / history of subfertility
IUD in situ
Smoking
What are the symptoms and signs of ectopic pregnancy?
Symptoms: Severe lower abdominal pain (IF normally) referred to the shoulder tip Rectal pain PV bleeding Anaemia, N&V, syncope May present like gastroenteritis
Signs:
Tachycardia, hypotension
Adnexal tenderness, cervical excitation
Peritonism
May be completely asymptomatic
How should you investigate somebody with ectopic pregnancy?
A-E assessment and full set of obs
-> if unstable, fluid/blood resuscitation and emergency surgery
If stable: Abdominal and PV examination Bloods: FBC, B-HCG, group and save +/- progesterone TV USS Abdominal USS
How can ectopic pregnancy be managed?
- Expectant
If asymptomatic and clinically stable
Serial 48hourly B-HCG until starts to fall and indicate failing pregnancy, then weekly - Medical
For clinically stable, asymptomatic patients
Single dose IM methotrexate 50mg/m2
HCG measurement 48 hourly and if insufficient fall (<15%) in a week, second dose
Can take up to 2 months for hormones to normalise - Surgical
Laparoscopic salpingectomy - fertility reduced to 70%
salpingotomy can be done to remove the pregnancy but remove the tube, but increased risk of recurrent disease
Emergency laparotomy
May need anti-D
What happens in the first stage of labour?
Latent phase:
Pressure of the baby’s head on the closed cervix leads to stretching and the release of oxytocin and prostaglandins.
Oxytocin causes uterine contraction, pushing the head down onto the cervix to reinforce this cycle.
Prostaglandins soften and ripen the cervix in preparation for it to dilate, as well as causing more uterine contractions.
Initial contractions -> dilation of 5cm.
Active phase:
Regular, painful contractions
Substantial cervical dilation from 5-10cm
What happens in the second stage of labour?
Full cervical dilation -> delivery of the baby
- Descent
- Flexion
- Internal rotation to occipitoanterior position
- Extension: head emerges
- External rotation back to transverse position, anterior shoulder delivered due to downward traction on the head
- Expulsion: posterior shoulder and rest of baby delivered
What happens in the third stage of labour?
Delivery of the placenta
3 signs: cord lengthening, uterine contraction, trickle of blood
Oxytocin given to encourage uterine contraction
Downward traction put on the cord, upward traction on the uterus to prevent inversion
What are the 4 causes of PPH?
Tone- uterine atony, no contraction to constrict spiral vessels and allow placental detachment
Trauma: trauma to the GU tract during labour
Tissue: retained products prevent uterine contraction
Thrombin: coagulopathy
What is the definition of a PPH?
Loss of over 500mls in vaginal delivery or over 1L in cesarean
How would you manage a patient with PPH?
A-E assessment
Lie patient flat and keep warm
IV access with 2 large bore cannulae
Bloods: FBC, clotting, group and save
Attempt to manually rub up a contraction, give oxytocin/ergometrine
Activate major haemorrhage protocol if continuous
May need: Balloon tamponade or emergency hysterectomy
Anti-D
What is the definition of preterm labour?
Delivery between 24 and 37 weeks gestation
What are the risk factors for preterm labour?
Extremes of maternal age Low maternal BMI Maternal smoking LLETZ procedure Poly/oligohydramnios Previous pre-term labour Multiple pregnancy Pre-eclampsia Vaginal infection such as BV
How should you investigate somebody presenting with preterm labour?
Bloods: FBC, CRP to look for infection, group and save
Vaginal and cervical swabs for infection
USS and CTG for foetal presentation, weight and status
Foetal fibronectin- if negative, chance of labour within 7-10 days very low
How would you manage preterm labour?
If high risk of actual labour, admit to obstetric ward
CTG monitoring
Maternal monitoring
12mg IM beclometasone- 2 doses, 24 hours apart for lung maturation
MgSO4 for neuroprotection
Consider tocolysis if <24 hours: nifedipine, atosiban IV
IV antibiotics if labour has been confirmed
How can preterm labour be prevented in high risk mothers?
Treatment of any infections
-> treat BV with clindamycin rather than metronidazole
Vaginal progesterone
Cervical cerclage/sutures: elective in women with hx of cervical weakness or as a rescue treatment for cervical dilation but no rupture
What is the key sign of uterine rupture?
Severe abdominal pain with palpable foetal parts abdominally
Maternal shock and vaginal bleeding
How is uterine rupture managed?
Maternal resuscitation
Emergency laparotomy: CS and uterine repair/hysterectomy
What are the differentials for antepartum haemorrhage?
Bleeding >24 weeks
Placental abruption Placenta praevia Vasa praevia Cervical ectropion/polyp GU infection Tract trauma
What should you always exclude before doing PV examination in a bleeding pregnant woman?
Placenta praevia
How would you approach a woman bleeding in pregnancy?
A-E assessment, full set of obs and full history
Uterine palpation
Exclusion of PP -> PV examination and speculum
Bloods: FBC, group and save, clotting, rhesus status
CTG
USS
What are the risk factors for placental abruption?
Maternal smoking, cocaine use, abdominal trauma, pre-eclampsia
How does placental abruption present?
Sudden onset abdominal pain Woody hard uterus, extremely tender May also have back pain PV bleeding- may be concealed Maternal instability and collapse
How is placental abruption managed?
A-E assessment
Resuscitation if needed
CTG
IV access and Bloods: FBC, group and save, clotting
If compromise: steroids and deliver
If stops: expectant management and safety netting
How does placenta praevia present?
Painless vaginal bleeding
Abdomen non-tender
Maternal haemodynamic instability
May be found incidentally or on scans
How is placenta praevia managed?
If complete occlusion of the os and previous bleeding: admit from 34 weeks
-> can be at home if asymptomatic and near hospital
If <2cm from os, CS indicated
Resuscitation of mother if major bleed and delivery of baby
How does vasa praaevia classically present?
PV bleeding after rupture of membranes
Rapid foetal distress
What are the indications for operative vaginal delivery?
Obstruction of labour
Maternal exhaustion and second stage pushing >1 hour (2hr in primip)
Inability to push e.g. neurological conditions
Foetal compromise
What are the key risks of forceps delivery?
Maternal genital tract trauma
Foetal facial trauma or facial nerve paralysis, IC haemorrhage rarely
What are the key risks of ventousse delivery?
Cephalohaematoma
Foetal scalp laceration
Retinal haemorrhage
More likely to fail
Should not be used <34w
When should OVD be abandoned?
If no progress after 3 contractions
Management of breech presentation
If breech at 20w, repeat scan at 36 weeks
If still breech at 36, offer ECV at 37 weeks
If still breech, elective C section recommended after 39 weeks
What are the main causes of subfertility?
Ovarian: hypothalamic/pituitary dysfunction, low BMI, PCOS, premature ovarian failure
Tubal: cystic fibrosis, previous PID/untreated STI, salpingectomy, endometriosis, adhesions
Uterine: large fibroids, endometriosis, malignancy, Asherman’s syndrome (adhesive scarring in endometrium)
Male: reduced number/motility/quality of sperm, retrograde ejaculation, gym supplements, tight clothes
How should subfertility be investigated?
- Full sexual history + establish frequency of sex
- > should be 2-3x weekly with regular periods over 2 years - Serum FSH, LH + oestradiol
- Progesterone day 21 to look at ovulation
- If irregular periods: testosterone/androgens as well as FSH + LH
- AMH for ovarian reserve
- Cervical smears and infection screen
- TVUSS
- Semen analysis: 2 samples, 3 months apart
How would you differentiate between hypothalamic/pituitary and ovarian subfertility?
Hypothalamic/pituitary: FSH, LH and estradiol are all low
In ovarian:
PCOS: Raised LH with normal FSH and oestradiol
In premature ovarian failure: Raised FSH and LH, low oestradiol
How can subfertility be managed?
- Clomiphene can be used in menstrual irregularity e.g. PCOS
- Gonadotrophin injections e.g. FSH to encourage ovulation
- Ovarian drilling
- IVF
- ICSI if sperm immobile
- Egg/sperm donors if premature ovarian failure or azoospermia
What are the symptoms of ovarian hyper stimulation syndrome?
Rapid weight gain and ascites Severe abdominal pain Nausea and vomiting Blood clots and shortness of breath Oliguria
What are the symptoms of obstetric cholestasis?
Epigastric pain
Pruritus with NO RASH
Anorexia and malaise
Steatorrhoea and dark urine
How is obstetric cholestasis managed?
LFTs and bile acid studies Vitamin K supplementation Ursodeoxycholic acid to reduce pruritus Foetal surveillance Post-natal LFTs
What are the causes of increased nuchal translucency?
Trisomy syndromes
Congenital heart defects
Abdominal wall defects
What is the Bishop score?
A score used to quantify the need for induction.
It takes into account cervical characteristics (position, consistency, effacement and dilatation) and foetal station. A Bishop score less than 5 generally means induction will likely be necessary. A score above 9 indicates labour will likely occur spontaneously.
Higher score= less need for induction
