Medications during pregnancy

Question 1

How do you alter care for someone with hypothyroidism during pregnancy? [1]

Answer 1

Untreated or under-treated hypothyroidism in pregnancy can lead to several adverse pregnancy outcomes, including miscarriage, anaemia, small for gestational age and pre-eclampsia.

Levothyroxine can cross the placenta and provide thyroid hormone to the developing fetus. The levothyroxine dose needs to be increased during pregnancy, usually by at least 25 – 50 mcg (30 – 50%).
- Treatment is titrated based on the TSH level, aiming for a low-normal TSH level.

Question 2

How do you manage hypertension during pregnancy:
- which medicines should be stopped [3]
- which medicines can be continued [3]

Answer 2

Medications that should be stopped as they may cause congenital abnormalities:
* ACE inhibitors (e.g. ramipril)
* Angiotensin receptor blockers (e.g. losartan)
* Thiazide and thiazide-like diuretics (e.g. indapamide)

Continued:
* Labetalol (a beta-blocker – although other beta-blockers may have adverse effects)
* Calcium channel blockers (e.g. nifedipine)
* Alpha-blockers (e.g. doxazosin)

Question 3

Women with epilepsy should take [drug, dose & frequency] daily from before conception to reduce the risk of neural tube defects.

Answer 3

Women with epilepsy should take folic acid 5mg daily from before conception to reduce the risk of neural tube defects.

Question 4

Which anti-epileptic drugs are safe in pregnancy? [3]

Answer 4

Levetiracetam, lamotrigine and carbamazepine are the safer anti-epileptic medication in pregnancy

Question 5

Which anti-epileptic drugs are not safe in pregnancy? [2]
Why/ [2]

Answer 5

• Sodium valproate is avoided as it causes neural tube defects and developmental delay
• Phenytoin is avoided as it causes cleft lip and palate
  *

Question 6

Which drugs are considered safe in pregnancy for patients with RA? [3]
Which is first line? [1]

Answer 6

• Hydroxychloroquine is considered safe during pregnancy and is often the first-line choice
• Sulfasalazine is considered safe during pregnancy
• Corticosteroids may be used during flare-ups

Question 7

Describe the risk / benefits of when considering medication in pregnancy [2]

Answer 7

When prescribing:
 benefit to the mother should always outweigh risk to fetus
 the risk of acute maternal disease may be greater than risk of teratogenicity

Question 8

How does pregnancy alter PK of drugs? [4]

Answer 8

Slow gastric emptying and reduced absorption of drugs

Increased maternal plasma volume: causes lowered serum levels of drugs making them ineffective eg anticonvulsants

Increased maternal hepatic metabolism: causes plasma levels of drugs to fall

Increased renal perfusion and elimination of drugs: cleared by the kidneys in pregnancy causes plasma levels to drop

Question 9

Name three drugs that have increased renal perfusion during pregnancy [3]

What is the clinical significance of this? [1]

Answer 9

Amoxicillin, Digoxin, Lithium
- Increased renal perfusion and elimination of drugs: cleared by the kidneys in pregnancy causes plasma levels to drop

Question 10

What is the difference between a teratogen and drugs that cause adverse fetal effects? [1]

Answer 10

Agents that cause permanent alteration of form or function

Question 11

Retinoids cause teratogenicity via which mechanism? [1]

Answer 11

Neural crest cell disruption

Question 12

DES, Fertility drugs, OCP cause teratogenicity via which mechanism? [1]

Answer 12

Endocrine disruption

Question 13

trimethoprim causes teratogenicity via which mechanism? [1]

When can / can’t trimethoprim be given during pregnancy? [1]

Answer 13

Folate antagonism
- not recommended in the first 12 weeks

Question 14

misoprostol, aspirin, ergotamine cause teratogenicity via which mechanism? [1]

Answer 14

Vascular disruption

Question 15

A patient presents with these teeth - which drug was likely used during pregnancy to cause this? [1]

Answer 15

Tetracyclines

Question 16

A patient presents with this problem - which drug was likely used during pregnancy to cause this? [1]

Answer 16

Phenytoin induced cleft palate

Question 17

A baby is born like this - what was likely taken to cause this? [1]

Answer 17

Thalidomide

Question 18

What is the dose of folic acid should take pre-conception for:
- healthy women [1]
- NTD, epilepsy, multiple pregnancy, SCD [1]

Answer 18

Start Folic Acid x 2-3 months pre-conception
 400 micrograms/day – healthy women
 5 milligrams/day - NTD, Epilepsy, Multiple pregnancy, sickle cell disease

Question 19

Describe the effect of using tobacco during pregnancy [+]

Answer 19

Low birthweight,
microcephaly, facial clefts

Increased risks of placenta previa, placental abruption, ectopic pregnancy, and PPROM

Reduced fetal oxygenation resulting in IUGR

Question 20

Excessive alcohol consumption usually defined as >[]g/day during pregnancy [1]

Answer 20

Excessive alcohol consumption usually defined as >80g/day

Question 21

Describe the effects of alcohol consumption during pregnancy [2]

Answer 21

Associated with spontaneous miscarriage in first trimester, even with low levels of intake 1,2

Fetal alcohol syndrome with chronic exposure

Question 22

Describe the effets / presentation of fetal alcohol syndrome

Answer 22

• short palpebral fissure
• thin vermillion border/hypoplastic upper lip
• smooth/absent filtrum
• learning difficulties
• microcephaly
• growth retardation
• epicanthic folds
• cardiac malformations

Question 23

Effects of cocaine during pregnancy? [5]

Answer 23

• spontaneous miscarriage
• Facial and skeletal anomalies
• Intestinal atresia
• Mental & growth retardation
• Placental abruption

Question 24

Describe the effects of heroin, methadone or opiates during pregnancy

Answer 24

• Placental vasoconstrictor so IUGR can occur
• Mental & growth retardation
• Placental abruption

Question 25

Which non pharmacological drug is as effective as other anti emetics during pregnancy? [1]

Answer 25

Powdered root ginger as effective as other anti-emetics

Question 26

Describe the treatment ladder for HG [4]

Answer 26

Hyperemesis gravidarum treatment dependent on severity: anti-emetics + thiamine 1.5mg od + Prednisolone 16mg od + Parental fluids + TPN1

Question 27

Anti-acids during pregnancy - which are safe?
- H2 antagonists
- PPIs

Answer 27

H2 antagonists:
- Cimetidine and Ranitidine are safe

PPIs:
- Omeprazole - however used only for protracted cases where the above haven’t been effective

Question 28

Which analgesics are safe during pregnancy (include when they are / not safe w/ regards to gestation)

Answer 28

Paracetamol
- safe

Aspirin
- Best avoided in late pregnancy as labour delayed and prolonged and increased risk of maternal and fetal
haemorrhage

NSAIDs
- Avoid in general: causes closure of PDA, NEC & pulmonary hypertension

Opoids:
- in general safe in short term use
- If on long term opioids inform neonatal team at delivery- risk of neonatal withdrawal

Question 29

Which NSAID is preferred post-partum? [1]
Which opiod? [1]

Answer 29

Ibuprofen
Di-hydrocodiene or tramadol used at lowest dose for shortest duration

Question 30

Which laxatives should be avoidded as they can cause uterine contractions? [2]

Answer 30

Senna, Bisacodyl

Question 31

Which antifungals are safe [2] and unsafe [3]

Answer 31

Topical imidazoles (e.g. clotrimazole; econazole):
- Safe as poorly absorbed

Systemic antifungal (e.g. fluconazole,griseofulvin, terbinafine)
- unsafe
- Avoid pregnancy for at least 6 months after treatment completed

Question 32

Which of the following causes NTD and facial clefts during pregnancy

Rifampicin
Isoniazide
Ethambutol
Trimethoprim
Streptomycin

Answer 32

Which of the following causes NTD and facial clefts during pregnancy

Rifampicin
Isoniazide
Ethambutol
Trimethoprim
Streptomycin

Question 33

Which of the following causes ototoxicty during pregnancy

Rifampicin
Isoniazide
Ethambutol
Trimethoprim
Streptomycin

Answer 33

Which of the following causes ototoxicty during pregnancy

Rifampicin
Isoniazide
Ethambutol
Trimethoprim
Streptomycin & other aminoglycosides

NB: Erythromycin safe

Question 34

Which antibiotix drug class can cause dysplasia of bones if given during pregnancy? [1]

Answer 34

Tetracyclines

Question 35

β-blockers are effective and safe in the [] trimester.

Answer 35

β-blockers are effective and safe in the 3rd trimester.

Question 36

Which drugs are used to control hypertensive crises during pregnancy? [2]

Answer 36

IV labetalol or hydralazine are used to control hypertensive crises.

Question 37

Which drug is used for severe pre-eclampsia and eclampsia? [1]

Answer 37

MgS

Question 38

When is labetolol CI? [1]

Answer 38

Avoid Labetalol in asthmatics

Question 39

Which drugs are safe for gestation diabetes? [2]

Which should be avoided? [1]

Answer 39

Sulphonylureas can cause fetal hyperinsulinemia & neonatal hypoglycemia therefore best avoided

Metformin does not cross the placenta and is therefore safe in pregnancy.

Question 40

Which anticoagulants are safe / unsafe during pregnancy?

Answer 40

DOACS:
- Unsafe - cause bleeding risk

Low molecular weight heparins (LMWH) are safe in pregnancy

Warfarin
- unsafe

Question 41

What is the a potential risk of when give levothyroxine during pregnancy? [1]

Answer 41

Some suggested association with
unilateral kidney agenesis

Question 42

Which vaccines should be avoided in early pregnancy? [3]

Answer 42

Avoid rubella vaccine (although no evidence that it is teratogenic) and MMR or Polio in early pregnancy

Question 43

Describe the cART rec. for pregnancy [3]

Which drug should be given during labour? [1]

Answer 43

tenofovir DF or abacavir with emtricitabine or lamivudine as a nucleoside backbone.

During labour, zidovudine should be administered intravenously until the umbilical cord is clamped.

Question 44

Which drugs can be used to supress lactation (e.g. after perinatal death) [2]

Answer 44

Carbergoline
- now first line

Bromocriptine
- is a dopamine receptor agonist thus inhibits prolactin release