The effect of levothyroxine tablets on the menstrual period Levothyroxine is a drug used to treat hypothyroidism (low thyroid activity) or hypothyroidism. This synthetic hormone, which is prescribed and supplied under the name "levothyroxine", is used to compensate for the lack of natural thyroid hormone in the body. The use of this medicine may affect menstruation. Hypothyroidism is a decrease in the level of thyroid hormones (T3 and T4) in the body, which can interfere with ovulation and regular menstruation. In the following, we will learn about the side effects of levothyroxine tablets on menstruation. Effects of levothyroxine tablets on menstruation By increasing the levothyroxine hormone in the body, the level of thyroid hormones improves and hypothyroidism is minimized. This can help improve symptoms caused by thyroid hormone deficiency. Some of these symptoms are: fatigue, reduced physical strength, weight gain, depression and anxiety. If there are insufficient thyroid hormones in the body or there is a disorder that causes low thyroid hormone, the functioning of the body's systems may be affected. It can also include the ovulation and menstruation regulation system. This is why levothyroxine intake and proper regulation of thyroid hormones can affect the control of menstruation and its changes. Read more: **Does hypothyroidism cause menstrual irregularities?** ### **Effects of improper use of levothyroxine on menstruation** A number of side effects associated with levothyroxine that can affect menstruation include: - **incorrect use of drug dosage**: Improper or irregular use of levothyroxine can cause an imbalance of thyroid hormones and affect the menstrual cycle. - **Dose setting**: Often, it takes several weeks for thyroid hormones to balance after levothyroxine treatment is started or the dose is changed, and menstruation may be affected during this period. Read more: **How to take levothyroxine tablets correctly** **Does hypothyroidism pills delay periods?** Does levothyroxine cause period delay? Or does the thyroid pill have an effect on periods? We must say that with any hormonal change, the menstrual cycle can be affected. Hypothyroidism can lead to missed periods (irregular or delayed periods). Although not necessarily the cause of the problem, the hypothyroid pill may cause irregular periods. Irregular periods are listed as side effects of thyroid medication. In general, the effects of hypothyroidism on the menstrual period include: - **Delay or irregularity of the menstrual period:** The lack of thyroid hormones can affect the process of ovulation and the release of the egg from the ovary. As a result, it can lead to delayed or irregular menstruation. - **Decreasing the process of the ovulation system**: The lack of thyroid hormones can have a negative effect on the process of the ovulation system and cause a decrease in ovulation. Changes in the intensity and duration of the period: hypothyroidism may cause changes in the intensity and duration of the menstrual period, so that the bleeding may be more or less than usual. - **Not completing the menstrual period**: In some cases, hypothyroidism can lead to incomplete allocation of the menstrual period, which means that menstruation begins but does not complete completely. ### **How does thyroid hormone deficiency cause menstrual disorders?** The high level of prolactin hormone in hypothyroidism reduces the production of gonadotropin-releasing hormone (GnRH) in the hypothalamus. This issue reduces the production of ovulation stimulating hormones (FSH and LH) in the pituitary gland. These hormones are very important for the regulation and normal functioning of women's ovaries. A decrease in the level of these hormones as a result of an underactive thyroid can lead to menstrual disorders in women. Hypothyroidism can reduce ovulation and cause heavy periods. Changes in prolactin levels can also lead to thinning of the uterine lining and changes in the control of the pituitary gland over the ovaries. Both may cause amenorrhea. ### **What strategies are there to reduce the effect of levothyroxine on menstruation?** To reduce the effects of levothyroxine tablets on menstruation, you can use the following: 1. Accurate drug dosage adjustment: Accurate drug dosage adjustment can reduce side effects and facilitate the improvement of menstrual regularity. 2. **Regular follow-up with the doctor**: Keeping in constant interaction with your doctor and doing regular blood tests can help you better control your thyroid and menstruation. 3. **Healthy and varied nutrition:** Consuming healthy and varied food that contains essential vitamins and minerals helps to improve the regularity of the menstrual cycle. 4. **Reduce stress**: Stress can affect the balance of hormones. Use relaxing activities such as yoga, meditation, and breathing exercises to reduce stress. 5. **Consumption of herbal supplements**: Some herbal supplements such as some medicinal plants and extracts may help to improve menstruation. Before using any supplement, be sure to consult your doctor. 6. **Continuity in drug use**: Regular and timely use of levothyroxine drugs is very important. Finally, it should be said that hypothyroidism is controlled by taking levothyroxine tablets. With regular and correct use of medicine, the level of thyroid hormones is balanced and hormonal problems are controlled. ### Effects of discontinuing levothyroxine tablets on menstruation Discontinuing thyroid medications such as levothyroxine can cause irregular menstrual cycles. Other side effects of stopping thyroid medication include: - Changes in blood pressure - Fatigue - Muscle weakness - Joint pain - Depression - Memory problems - Weight gain - Hair loss - Insomnia - Rapid pulse or palpitations Thyroid medications can reduce menstrual cycle regulation by stimulating normal blood flow and ovulation. When thyroid hormone levels are too low or too high, it can cause irregular, heavy, or very light periods. Thyroid disease can also cause periods to stop for several months or longer, a condition known as amenorrhea. Dr. Seyed Ahmad Fanai is a thyroid and parathyroid surgeon and an active member of the American Association of Thyroid Surgeons (ATA). You can contact us for appointment and consultation.