21
Check TPOAb status
a
Start levothyroxine if
TSH >10 mU/L
and repeat FT4
Consider starting low
dose levothyroxine
Normal FT4
Increased TSH in
pregnancy
First
trimester
d
Consider
confirmation test
after 1–3 weeks
Second
d
or
third trimester
Check FT4
b
Subclinical
hypothyroidism
Recheck TSH
every 4–6 weeks, then
restart flowchart
Normalized TSH
Confirmed high TSH
c
For mild forms of overt hypothyroidism, the risk profile and chance of TSH normalization are
similar to subclinical hypothyroidism. erefore, confirmatory testing can be considered using a
shared decision-making approach.
d
e distinction between the first and second trimester remains arbitrary, and management can be
altered if the gestational age is within reasonable proximity on a case-by-case approach.
