Pregnancy

Question 1

what can hypo and hyperthyroidism lead to?

Answer 1

anovulatory cycles- reduced fertility

Question 2

why is maternal thyroxine important for neonatal development?

Answer 2

CNS development

Question 3

what can the increased demand of thyroxine in pregnancy lead to?

Answer 3

enlarged thyroid gland

Question 4

what is unable to compensate for the increased demand of thyroxine during pregnancy?

Answer 4

pre-existing hypothyroidism

Question 5

hypothyroidism management in pregnancy

Answer 5

increase thyroxine dose by 25mcg as soon as pregnancy expected
check TFTs monthly for first 20 weeks then every 2 months until term

Question 6

average dose increase of levothyroxine in pregnancy

Answer 6

increases by 50%, aim for TSH <3mU/l

Question 7

risks of untreated hypothyroidism in pregnancy

Answer 7

increased abortion
pre-eclampsia
abruption
postpartum haemorrhage
preterm labour
foetal neurophysiological development (average IQ 7 points lead and increased risk of IQ below 85)

Question 8

what does hCG do?

Answer 8

increases thyroxine which suppresses TSH

Question 9

what is hCG a similar structure to?

Answer 9

TSH

both have two peptide chains with an identical chain

Question 10

abnormal thyroid function tests in pregnancy

Answer 10

hCG effect (TSH-like effect): T4 increased, low TSH (mimics hyperthyroidism)

Question 11

what does the hCG effect cause?

Answer 11

hyperemesis gravidarum

Question 12

what distinguishes hyperemesis from hyperthyroidism (gestational hCG-associated thyrotoxicosis)

Answer 12

hyperemesis gravidarum= high hCG and low TSH
not TRAb antibody positive
resolves by 20 weeks gestation
only treat if persists beyond 20 weeks

Question 13

complications in pregnancy for hyperthyroidism

Answer 13

infertility/amenorrhoea
spontaneous miscarriage
still birth
thyroid crisis in labour
transient neonatal thyrotoxicosis

Question 14

causes of thyrotoxicosis in pregnancy

Answer 14

Grave’s
TMNG, toxic adenoma
thyroiditis

Question 15

hyperthyroidism management in pregnancy

Answer 15

• wait and see (maybe hyperemesis)
• Grave’s may settle as pregnancy suppress AI
• beta blockers
• low dose ATD

Question 16

why is hyperemesis difficult to distinguish from hyperthyroidism?

Answer 16

both present with nausea, vomiting, tachycardia, warm, sweaty and lack of weight gain

Question 17

ATDs in pregnancy

Answer 17

PTU for first trimester then carbimazole for 2-3rd trimesters

Question 18

adverse of carbimazole

Answer 18

embryopathy in 1st trimester

Question 19

adverse of PTU

Answer 19

liver toxicity (best avoided except first trimester)

Question 20

when should TRAb antibodies be checked in pregnancy?

Answer 20

third trimester

Question 21

why should you check TRAb antibodies?

Answer 21

if present alert neonatologist

TRAb can cross placenta and cause neonatal transient hyperthyroidism

Question 22

what is there an increased risk after pregnancy of in T1DM?

Answer 22

post-partum thyroiditis

Question 23

what can the transient thyrotoxic state cause after pregnancy?

Answer 23

hypothyroidism which can persist for up to 1 year

Question 24

presentation of hypothyroidism

Answer 24

small diffuse non-tender goitre
hypothyroid phase is associated with postnatal depression
postpartum exacerbation of all AI

Question 25

drugs that cause galactorrhoea

Answer 25

metoclopramide
cocaine
anti-psychotics (dopamine antagonists)