Does Thyroid Medication Affect The Menstrual Cycle?

By increasing your thyroid hormone, your hypothalamus will decrease TRH release, thus decreasing TSH and prolactin release. Your menstrual cycle requires a delicate balance of your hormones, including estrogen and progesterone. But, an imbalance in other hormones not directly related to your menstrual cycle can influence reproductive hormone levels and cause AUB. The hypothalamic-pituitary-thyroid axis and the hypothalamic-pituitary-gonadal axis are physiologically intertwined. The function of the thyroid is under the control of the hypothalamic-pituitary-thyroid axis.

Associated Data

In a prospective cohort study of euthyroid women, this study characterized the relationship between thyroid hormone concentrations and prospectively-collected menstrual function outcomes. Cushing’s syndrome (CS) is a rare endocrine disorder (85), with an incidence rate of estimated to be per million (86). The related clinical signs of hypercortisolism in CS include obesity, hirsutism, hypertension, protein wasting signs, menstrual irregularity (oligoamenorrhea, amenorrhea). Menstrual irregularity is the most common complaint in Cushing’s syndrome (28). Clinical and biochemical signs of hyperandrogensim are more commonly manifested in women with CS (88).

Table 1. The Hormonal Changes and Results of Menstrual Disturbances That Were Observed in Various Endocrine Disorders.

• This study is similar to a study carried out by Kaur et al.17 and Singh P et al.18 in which polymenorrhoea was second most complain accounting for 37.5% cases.
• Start your journey toward improved thyroid and menstrual health with Everlywell.
• Different types of studies (review, observational, experimental) relevant to the subjects were reviewed.
• Cushing’s syndrome (CS) is a rare endocrine disorder (85), with an incidence rate of estimated to be per million (86).

After graduation, Emilie completed a postgraduate pharmacy residency at Bon Secours Memorial Regional Medical Center in Virginia. Her background includes caring for critical care, internal medicine, and surgical patients. If your thyroid biomarkers are abnormal, Paloma has an expert team of thyroid specialists who can help you develop a comprehensive, personalized treatment plan. The American College of Obstetrics and Gynecology recommends checking a TSH level in AUB patients. If you have AUB and haven’t checked your TSH, speak with your healthcare provider. The study and control groups were comparable in respect of age, religion, and socioeconomic status.

Genetics and Deoiodination in Hashimoto’s and Hypothyroidism

This emphasizes the significance of estimation of thyroid antibodies in patients with menstrual disorder. Different authors have used different methods for Anti-TPO antibody assay, and their results may vary with kits from different manufacturers. Our samples were evaluated for Anti-TPO Antibody using ELISA microwell kit (Xema Co., Ltd, Germany), with cutoff value 75 IU/ml.

Additionally, many did not include patients with subclinical hyperthyroidism or subclinical hypothyroidism 2. In our study, of total 17 hypothyroid patients, most of the patients had menorrhagia followed by polymenorrhea, hypo/oligomenorrhea, and metrorrhagia. Kaur 12 observed that among 14 hypothyroid patients, 9 (64.3 %) had menorrhagia, 3 (21.4 %) had oligomenorrhea, and 2 (14.28 %) had metrorrhagia. Pahwa 13 found a total of 22 hypothyroid patients, in which 16 (78.94 %) had menorrhagia and 4 (10.5 %) had polymenorrhea. In the study by Padmaleela 14, the commonest menstrual complaint was menorrhagia (53.3 %) followed by polymenorrhea (13.3 %), and 20 % had hypo/oligomenorrhea in hypothyroid patients, which goes with our study.

Thyroid dysfunction has a great impact on reproductive function before, during, and after pregnancy. The most common endocrine condition affecting women’s reproduction is thyroid disorder 1. We recommend its testing as a routine test in the evaluation of patients with menstrual disorders. However, prospective studies are required to analyze the cost effectiveness of anti-TPO antibody testing and its possible benefits with regard to treatment. Menorrhagia was the most common complaint among the patients with menstrual disorders, and most of the patients in other groups presented with white discharge in our study. Similar were observations of Pahwa 13 (50 %) and Padmaleela 14 (50 %), where menorrhagia was the most common complaint.

Among hypothyroid cases 7 (8.8%) had subclinical and 4 (5.06%) had overt hypothyroidism. This study is similar to study carried out by Kumar AHS et al.22 in which out of 200 cases 162 (81 %) cases were euthyroid, 38 (19%) cases had thyroid dysfunction out of which 33 (16.5%) were hypothyroid and 5 (2.5%) were hyperthyroid. Among hypothyroid 21 cases (10.5%) were subclinical and 12 (6%) has overt hypothyroidism. The most common type of abnormal uterine bleeding in this study was also menorrhagia. In another study done by Gowri M et al.21 out of 170 cases, 132 (77.6%) cases were euthyroid, 30 (17.6%) of cases had hypothyroidism and 8 (4.7%) had hyperthyroidism. The most common bleeding disorder in this study was oligomenorrhoea followed by menorrhagia and hypomenorrhea.

One of the most common clinical features of CS in female patients is menstrual irregularity (80%) (89). In the European Registry on CS, in 390 female patients, 56% had menstrual irregularity (90). Similarly, Bolland et al. (91) observed that 35.5% of women with CS in a New Zealand nationwide survey, presented with menstrual irregularity.

Models for E13G and Pd3G were aligned by the estimated day of ovulation ± 10 days and for E13G, Pd3G, and FSH by menses onset (5 days before menses onset through cycle day 4 of the next cycle). If you’re currently on thyroid medication or experiencing symptoms related to thyroid dysfunction, Everlywell provides an at-home Thyroid Test that can measure your current levels of thyroid hormones and thyroid antibodies. These medications work to decelerate the production of thyroid hormones and can take effect within weeks. Accordingly, they can help reregulate the menstrual cycle to stimulate normal blood flow and regular ovulation. More permanent treatment options can include iodine treatment or oracea synthroid surgical removal of the thyroid; however, these options can also lead to an underactive thyroid.

Irregular bleeding with ovulatory dysfunction in women at childbearing age is commonly caused by PCOS (34). Recently, PCOS has been recognized as the most common problem in endocrine practice (35). Strowitzki et al. (39) investigated 118 German women with PCOS and showed that the degree of menstrual cycle irregularity indicated the degree of the endocrine disorder in these patients. Maslyanskaya et al. (40) reported that PCOS is an under-recognized cause of abnormal uterine bleeding (AUB) in teenagers admitted to health care institution. In the Tehrani et al. (37) study conducted on Iranian women, the subclinical menstrual dysfunction was diagnosed among 11.3% of women with hirsutism (26). Even in the setting of normal thyroid function, thyroid autoimmunity may significantly affect reproductive activity and pregnancy.