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How can thyroid disease interfere with ovulation?

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Diagram showing the female reproductive system with labeled ovaries, fallopian tubes, uterus, and vagina, alongside hormone pathways and the process from ovulation to fertilization and early embryo development. — infertility Major structures and hormones involved in the initiation of pregnancy. Also seen, at right, is the development of an egg cell (ovum) from follicle to embryo.

Thyroid disease can interfere with ovulation by disrupting the delicate hormonal balance required for the reproductive system to function correctly.

In cases of hypothyroidism (a deficiency of thyroid hormone), the body may experience a decrease in the production of gonadotropins—the hormones responsible for stimulating the ovaries. When these associated hormone levels drop, it can lead to amenorrhea, or the cessation of menstrual cycles, which prevents normal ovulation.1

Furthermore, thyroid dysfunction can cause irregular menstrual patterns, such as excessive bleeding (menorrhagia), which reflects broader ovarian dysfunction. Because ovulation relies on precise signaling—including the release of luteinizing hormone—any significant endocrine imbalance caused by thyroid disease can reduce overall fertility. Fortunately, when thyroid deficiency is addressed through appropriate medical treatment, such as thyroid hormone replacement, these reproductive disruptions can often be corrected.123