From the Research
Yes, hyperthyroidism can disrupt menstrual periods, leading to irregularities such as oligomenorrhea, amenorrhea, or changes in menstrual flow. When the thyroid gland produces excessive thyroid hormones, it can interfere with the normal hormonal balance that regulates the menstrual cycle. Women with hyperthyroidism commonly experience irregular periods, lighter bleeding, less frequent periods, or even complete absence of periods. This happens because thyroid hormones interact with sex hormones like estrogen and affect the hypothalamic-pituitary-ovarian axis that controls menstruation. The excess thyroid hormones can alter the production of luteinizing hormone (LH) and follicle-stimulating hormone (FSH), which are essential for normal ovulation and menstruation 1.
Key Findings
- Hyperthyroidism can cause menstrual disturbances, including oligomenorrhea, amenorrhea, and changes in menstrual flow 2, 3.
- The prevalence of menstrual disturbances in hyperthyroidism is higher in severe cases than in mild or moderate cases 3.
- Treatment of the underlying hyperthyroidism with medications like methimazole or propylthiouracil, radioactive iodine therapy, or in some cases thyroid surgery, typically resolves these menstrual irregularities once thyroid hormone levels return to normal 4, 1.
- It is essential to get thyroid function tests to determine if hyperthyroidism is the cause of menstrual changes 1.
Clinical Implications
- Hyperthyroidism should be considered as a potential cause of menstrual irregularities in women of reproductive age.
- Thyroid function tests should be performed in women with menstrual changes to rule out hyperthyroidism.
- Treatment of hyperthyroidism can help resolve menstrual irregularities and improve overall health outcomes.