Thyroid problems and menstrual cycles: Periods, fertility, and associated factors
Hyperthyroidism and its Impact on Menstrual Cycles and Fertility
Hyperthyroidism, a condition where the thyroid gland produces excess thyroid hormones, can have a significant impact on a person's menstrual cycle and reproductive health.
Disruption of Menstrual Cycles
Hyperthyroidism often causes shorter or more frequent menstrual cycles, known as rapid cycling. These cycles, however, may not include ovulation, making conception difficult [1]. Women with hyperthyroidism may experience cycle lengths reduced from the typical 28 days down to as little as 10–12 days in extreme cases [1].
Effects on Fertility
The imbalance of thyroid hormones disrupts the hormonal regulation of the menstrual cycle, affecting the production of estradiol and progesterone, which are essential for ovulation and fertility [2]. Hyperthyroidism can also impair ovulation, making it more difficult to conceive [3].
Anovulatory Cycles
One of the primary ways hyperthyroidism affects fertility is by causing anovulatory menstrual cycles, where no egg is released [1]. This lack of ovulation makes it impossible for pregnancy to occur.
Other Fertility Issues
Hyperthyroidism can lead to low levels of sex hormone binding globulin (SHBG), which may cause fertility problems [4]. Additionally, high levels of the hormone prolactin in the blood, which can occur due to hyperthyroidism, can affect menstruation, ovulation, and fertility [5].
Risks in Pregnancy
Hyperthyroidism in pregnancy carries risks to both the parent and baby, so a doctor will need to closely monitor any pregnancy [6].
Preventive Measures
Limiting or avoiding sources of iodine, such as iodine supplements, foods containing iodine like kelp and iodized table salt, certain multivitamins, and cough syrups, can help reduce symptoms of hyperthyroidism [7].
Other Health Risks
Untreated hyperthyroidism can lead to severe health problems such as osteoporosis, irregular heartbeat, stroke, and other heart-related problems [8].
Implications for Immune System Disorders
If the immune system is the cause of a person's hyperthyroidism, it may lead to premature menopause before the age of 40 [9].
Smoking and Hyperthyroidism
Smoking may contribute to the development of hyperthyroidism [10].
Symptoms of Hyperthyroidism
Symptoms of hyperthyroidism include irregular or rapid heartbeat, diarrhea, unexplained weight loss, increased appetite, irritability, trembling fingers or hands, anxiety or nervousness, difficulty sleeping, sweating more than usual, weak muscles, redness, bulging, or irritation in the eyes, feeling hot when others do not, and ocular symptoms like Graves' ophthalmopathy [11].
In summary, hyperthyroidism disrupts menstrual regularity and ovulation, impairing fertility, but these effects are generally reversible with appropriate treatment. It is crucial for individuals with hyperthyroidism to seek medical advice to manage their condition and protect their reproductive health.
Women with hyperthyroidism may experience shorter or more frequent menstrual cycles, known as rapid cycling, which can disrupt the production of estradiol and progesterone, essential hormones for ovulation and fertility. Hyperthyroidism can also lead to anovulatory menstrual cycles, where no egg is released, making it impossible for pregnancy to occur. Other fertility issues related to hyperthyroidism include low levels of sex hormone binding globulin and high levels of prolactin, both of which can affect menstruation, ovulation, and fertility. Seeking medical advice for hyperthyroidism is crucial for individuals to manage their condition and protect their reproductive health. Untreated hyperthyroidism can lead to severe health problems, including premature menopause, osteoporosis, irregular heartbeat, stroke, and other heart-related problems.
