Can people with thyroid problems have children?

Absolutely yes. Having a thyroid disorder does not mean you can’t become pregnant.
Thyroid conditions should be identified early and, when necessary, treated appropriately. With proper management, there is no obstacle to normal fertility or a healthy pregnancy.

I have a low TSH level in the first trimester. Do I have a thyroid disorder?

Not necessarily.
In the first trimester, the hormone hCG (human chorionic gonadotropin), produced by the placenta, stimulates the TSH receptor, increasing thyroid hormone production.
As a result, the serum TSH level naturally drops, even in the absence of thyroid disease.
So a low TSH in early pregnancy can be completely physiological.

What causes hypothyroidism during pregnancy?

In most cases, hypothyroidism in pregnancy is autoimmune—commonly due to Hashimoto’s thyroiditis.
This condition occurs when the immune system mistakenly attacks the thyroid gland, leading to its progressive loss of function.

In early pregnancy, the maternal thyroid must work harder, especially during the first trimester, as the fetus doesn’t yet produce its own thyroid hormones.
Even women with normal thyroid function or mild hypothyroidism may develop full-blown hypothyroidism in the early weeks.

What problems can hyperthyroidism cause in pregnancy?

Hyperthyroidism during pregnancy is rare, but when it occurs—often due to Graves’ disease (autoimmune)—it can lead to the transmission of stimulating antibodies to the fetus, potentially causing fetal hyperthyroidism.

If left untreated, maternal hyperthyroidism can lead to serious complications for both the mother and the baby.

When should hypothyroidism be treated during pregnancy?

Ideally, thyroid conditions should be diagnosed before conception. This involves:

  • A blood test for TSH and FT4 (thyroid hormones)
  • Screening for thyroid antibodies (Anti-TPO, Anti-Tg)

Both clinical and subclinical hypothyroidism should be treated with thyroxine (levothyroxine) before pregnancy.
Even thyroiditis with normal hormone levels should be monitored closely and thyroid function re-tested in early pregnancy to determine if treatment is needed.

Adequate levels of thyroid hormones are essential to prevent skeletal and brain developmental abnormalities in the fetus.

How is hyperthyroidism treated during pregnancy?

The first-line treatment for hyperthyroidism in pregnancy is antithyroid medication, particularly propylthiouracil (PTU), known by the brand name Propycil.

What is the role of thyroid ultrasound in pregnancy?

A thyroid ultrasound can help assess the structure and appearance of the thyroid gland.
It is especially useful when:

  • Thyroid dysfunction is suspected (hypo- or hyperthyroidism)
  • There are thyroid nodules—which may increase in size due to the physiological hormonal demands of pregnancy

Ultrasound provides valuable complementary information alongside blood tests.