Prescribing in Pregnancy

Question 1

what drugs cannot cross the placenta?

Answer 1

large molecule weight drugs i.e. heparin

Question 2

what drugs cross the placenta most easily?

Answer 2

small, lipid soluble drugs

Question 3

what should be given prior to conception and for how long?

Answer 3

folic acid 400mg daily for three months prior to conception

then also for the first three months of pregnancy

Question 4

when is the period of greatest teratogenic risk?

Answer 4

4-11 weeks

Question 5

when could drug exposure result in intellectual and behavioural abnormalities?

Answer 5

second and third trimesters

Question 6

what possible adverse effects can drugs have on labour?

Answer 6

impacts on progress
premature closure of DA
suppression of foetal systems
bleeding

Question 7

name a drug that can cause bleeding in labour

Answer 7

warfarin

Question 8

name a drug that can suppress a foetal system during labour

Answer 8

opiates

can cause respiratory depression

Question 9

why can there be an increase in the number of seizures experienced by epileptic patients during pregnancy?

Answer 9

non compliance

changes in plasma concentrations of drugs

Question 10

what are frequent epileptic seizures in pregnancy associated with?

Answer 10

lower IQ
hypoxia
bradycardia 
antenatal death 
maternal death

Question 11

what is the preferred management structure for epilepsy in pregnancy and why?

Answer 11

mono therapy

more drugs = more risk of malformations

Question 12

what anti-epileptics should be avoided in pregnancy?

Answer 12

valproate

phenytoin

Question 13

what dose of folic acid should women with epilepsy take during pregnancy?

Answer 13

5mg daily

Question 14

is insulin a safe option during pregnancy?

Answer 14

yes

however, requirements will change during pregnancy

Question 15

what does poor diabetic control increase risk of?

Answer 15

congenital malformation

intra-uterine death

Question 16

what diabetic drug is not safe in pregnancy and what change should be made?

Answer 16

sulphonylureas

change to insulin

Question 17

what happens to blood pressure in pregnancy?

Answer 17

falls in the second trimester

Question 18

what are the three options for anti-hypertensives in pregnancy?

Answer 18

labetalol
methyldopa
nifedipine MR

Question 19

what anti-hypertensives should be avoided in pregnancy and why?

Answer 19

ACE + ARBs

can cause foetal abnormalities

Question 20

what effect can beta blockers have in pregnancy?

Answer 20

may inhibit foetal growth in late pregnancy

Question 21

what is the first line anti-emetic in pregnancy?

Answer 21

cyclizine

Question 22

what antibiotics can be used to manage UTI in pregnancy?

Answer 22

nitrofurantoin
cefalexin
trimethoprim (in third trimester)

Question 23

what is the first line analgesic in pregnancy?

Answer 23

paracetamol

Question 24

what prophylaxis is given for VTE in pregnancy, who gets it and when?

Answer 24

LMWH

those with two or more risk factors

at delivery and for up to seven days postpartum

Question 25

what are the risk factors for VTE in pregnancy?

Answer 25

obesity 
age >35 
smoking 
para >3 
previous DVT 
C section

Question 26

why should warfarin be avoided in pregnancy?

Answer 26

teratogenic

risk of haemorrhage during delivery

Question 27

how is VTE treated in pregnancy?

Answer 27

therapeutic dose of LMWH