Can thyroid disease cause problems getting pregnant?

Both hyperthyroidism and hypothyroidism can make it harder for you to get pregnant. This is because problems with the thyroid hormone can upset the balance of the hormones that cause ovulation. Hypothyroidism can also cause your body to make more prolactin, the hormone that tells your body to make breastmilk. Too much prolactin can prevent ovulation.

Thyroid problems can also affect the menstrual cycle. Your periods may be heavier or irregular, or you may not have any periods at all for several months or longer (called amenorrhea).