Obstetrics Flashcards
What are the risks of asymptomatic bacteriuria in pregnancy?
Increased risk of preterm delivery
Increased risk of pyelonephritis during pregnancy
How should asymptomatic bacteriuria be treated?
Immediate antibiotic prescription (nitrofurantoin, amoxicillin or cefalexin)
Which tests are done at the booking visit?
FBC
MSU
Blood group and antibody screen
Infection screen (Hep B, HIV, Syphilis)
When does gestational thrombocytopaenia tend to occur?
> 28 weeks
What should women with a history of GDM be offered in their pregnancy?
OGTT or random blood glucose in the 1st trimester
NOTE: helps identify pre-existing diabetes that has developed in the meantime
How should newborns born to women with hepatitis B be treated to reduce the risk of transmission?
Hepatitis B vaccine (at birth, 1 month and 6 months)
Hepatitis B immunoglobulin
NOTE: both should be given within 12 hours
Which parameters are used to date the pregnancy on ultrasound scan?
10-14 weeks = CRL
14-20 weeks = Head Circumference
What are the components of the combined test for Down syndrome?
Nuchal translucency
b-hCG
PAPP-A
What are the components of the quadruple test for Down syndrome?
b-hCG AFP Unconjugated oestriol Inhibin A NOTE: the triple test is a similar test that doesn't use inhibin A
What should be offered to women with a high risk of Down syndrome according to initial screening tests?
CVS (10-14 weeks)
Amniocentesis (15+ weeks)
cffDNA (only available privately)
NOTE: results take 48 hours
How often should SFH be measured?
Every antenatal appointment after 24 weeks
What should happen if there are concerns about foetal growth according to SFH measurements?
Organise an ultrasound
What is the NICE recommendation regarding vitamin D during pregnancy?
All pregnant and breastfeeding women should receive 10 µg vitamin D daily
When should an OGTT be performed in women with a high risk of GDM?
24-28 weeks
If previous history of GDM, this should be done at 16-18 weeks and a repeat at 24-28 weeks
What should be offered to women with a history of late pregnancy loss and a short cervix?
Prophylactic vaginal progesterone
Prophylactic cervical cerclage
How should PPROM be investigated?
Sterile speculum - pooling observed –> diagnose PPROM
No pooling –> test for IGF-like binding protein-1 and alpha-microglobulin-1 test
IMPORTANT: diagnostic tests should NOT be performed if the patient goes into labour
What antibiotic prophylaxis should be given to patients with PPROM?
Oral erythromycin 250 mg QDS for 10 days or until the woman is in established labour
Which women should be offered rescue cervical cerclage?
16-27 weeks with a dilated cervix and unruptured membranes
Do NOT perform if signs of infection, active vaginal bleeding or uterine contractions
Which investigations should be used to confirm a diagnosis of preterm labour?
If suspected preterm labour > 30 weeks
- Consider TVUSS to determine likelihood of birth within 48 hours (cervical length > 15 mm means it is unlikely)
- Consider fetal fibronectin (low concentration suggests it is unlikely)
IMPORTANT: if < 30 weeks and clinical assessment suggests preterm labour, treatment is necessary without further investigation
Which agent is most commonly used for tocolysis?
Nifedipine
If contraindicated: atosiban (oxytocin receptor antagonist)
Up to what gestation should maternal corticosteroids be considered in preterm labour?
36 weeks
Which agent is used for neuroprotection in preterm delivery?
IV magnesium sulphate 4 g IV over 15 mins (loading) and 1 g/hour until birth or for 24 hours
NOTE: this is used in women who are delivering at 24-34 weeks (most important for 24-30 weeks)
How is magnesium sulphate poisoning treated?
Calcium gluconate
Which parameters are measured in ultrasound biometry used to monitor foetal growth?
Biparietal diameter
Head circumference
Abdominal circumference
Femur length