Thyroid Problems and Pregnancy: A Guide for Pakistani Women

Thyroid disease — particularly hypothyroidism — is remarkably common in Pakistani women and frequently goes undiagnosed until pregnancy complications force testing. An underactive thyroid in early pregnancy is linked to miscarriage, preterm birth and impaired brain development in the baby.

We screen with a simple TSH blood test at the booking visit. If TSH is elevated, we add free T4 and thyroid antibodies. The target TSH in the first trimester is below 2.5 mIU/L — stricter than the non-pregnant range — because the baby depends entirely on maternal thyroid hormone in early development.

Treatment is straightforward: levothyroxine, taken on an empty stomach thirty minutes before breakfast. The dose often needs to increase by 25–50% in pregnancy because of rising hormone demands. We recheck TSH every four to six weeks and adjust accordingly.

Hyperthyroidism (overactive thyroid) is less common but equally important. Symptoms include weight loss despite good appetite, tremor, rapid heartbeat and heat intolerance. Uncontrolled hyperthyroidism increases the risk of preeclampsia, heart failure and fetal growth restriction. Treatment in pregnancy uses specific medications that are safer for the baby.

After delivery, thyroid function can fluctuate — postpartum thyroiditis affects up to 10% of women and can mimic postnatal depression. If you feel unusually tired, anxious, or low in the months after delivery, a thyroid check is always worthwhile.

If you have known thyroid disease and are planning a pregnancy, see your doctor beforehand. Adjusting your dose before conception gives the baby the best start.