How many antenatal visits is a multip likely to receive? And at what stages of her pregnancy will these be?
8 visits:
Booking visit (hx and bloods) ideally by 10/40
Dating scan at 11-13+6/40
Results at 16/40
Anomaly scan is at 18-20/40
Hb, antibodies, OGTT bloods. Anti-D given if necessary at 28/40
34/40
36/40
38/40
Offer membrane sweep and discuss induction 41/40
What are the two ways it is possible to estimate the date of delivery?
Menstrual EDD - The first day of the woman’s LMP is taken and 9 months + 1 week added to give an estimation of the due date
Dating scan EDD - More accurate than menstrual EDD, the dating scan at 11-13+6/40 is used to determine the due date based on the size of the foetus (which varies very little between pregnancies
True / False - All pregnant women are given an oral glucose tolerance test to screen for gestational diabetes
False - Women are risk assessed at booking and if they are deemed to be high risk they are offered a GTT at 24-28 weeks (earlier if previous gestational diabetes)
What does a ‘monozygotic’ multiple pregnancy mean?
Multiple embryos result from the mitotic division of a single zygote, and result in ‘identical’ twins
What does ‘dichorionic diamniotic’ multiple pregnancy mean?
Separate placenta, separate amniotic sacs
What does ‘monochorionic diamniotic’ multiple pregnancy mean?
Shared placenta, separate amniotic sacs
True / False: Sodium valproate is safe in pregnancy
False - Valproate is teratogenic and associated with neonatal seizures. It should be avoided in pregnancy.
True / False: Sodium valproate is a cytochrome p450 inhibitor
True - This means it reduces the efficacy of the COCP and should be avoided in women of childbearing age
Which trimester is trimethoprim considered unsafe and why?
Avoid in 1st trimester as it is a folate antagonist
Which trimester is nitrofurantoin considered unsafe and why?
Avoid in 3rd trimester as it is associated with fetal haemolytic anaemia
What is the ‘combined’ test and when is it done?
A test carried out between 10 and 14 weeks gestation which involves a blood test for beta-hCG and PAPP-A, and a nuchal translucency ultrasound scan
What is the ‘combined’ test aiming to detect?
Risk of Down’s syndrome primarily, but also Edward’s syndrome and Patau’s syndrome
Which test can a woman have for Down’s syndrome detection if she missed her ‘combined’ test screening?
The ‘quadruple’ test is still available to her
What is the ‘quadruple’ test and when can it be done?
Blood test for beta-HCG, AFP, oestriol, Inhibin A…carried out between 14 and 20 weeks
At what gestation can amniocentesis be carried out? What is the risk of misscarriage?
Performed after 15 weeks
1% risk of miscarriage
At what gestation can chorionic villus sampling be carried out? What is the risk of misscarriage?
Performed at 11-14 weeks
1-2% risk of miscarriage
Why does maternal BP drop in the first part of her pregnancy?
Decreased vascular resistance due to progesterone
What is the normal folic acid dose in pregnancy?
400mcg daily
What is the higher dose of folic acid recommended for high risk women?
5mg daily
Which women are recommended to take high dose (5mg daily) folic acid?
When either mother or father has neural tube defect
Previous pregnancy affected by neural tube defect
Fix of neural tube defect
Mother on anti-epileptic drugs
Chronic conditions: Coeliac disease, diabetes, thalassemia trait, Sickle cell
BMI above 30
How long should women take folic acid for during pregnancy?
Until 12/40
Until birth if thalassemia trait or other haemoglobinopathy
How do you determine whether a twin pregnancy is monozygotic or dizygotic?
Presence of a ‘lambda’ sign on ultrasound scan indicates dizygotic pregnancy - it is a triangular sign seen between the 2 amniotic fluid sacs (dizygotic pregnancies are always dichorionic)
List the different types of monozygotic twin pregnancy
Dichorionic diamniotic
Monochorionic diamniotic
Monochorionic monoamniotic
Conjoined twins
What determines the type of placenta seen in monozygotic twins?
The timing of the mitotic separation
