Menorrhagia and hypothyroidism: Evidence supports association between hypothyroidism and menorrhagia

In our study, the prevalence of hypothyroidism and hyperthyroidism in patients with menstrual disorders is almost two times higher than in the control population. In the study by Sharma 7, prevalence of hypothyroidism was detected in 22% patients of DUB and hyperthyroidism in 14 %. In the study by Pahwa 13, 22 % cases of hypothyroidism and 76 % of euthyroidism were reported, whereas Padmaleela 14 observed thyroid disorders in 26.5 % patients of DUB.

There are global variations synthroid samples in the incidence and prevalence of thyroid disorders (74) that the incidence of them in women is higher than in men (75, 76). Thyroid dysfunction, such as hyperthyroidism and hypothyroidism affect the reproductive health of women (77). Thyroid dysfunction can affect the normal menstrual cycle, sometimes presenting as AUB (78). Changes in menstrual cycle length and amount of bleeding often occur in women with hypothyroidism (27). In general, hypothyroidism causes different menstrual conditions such as irregular menses, heavy bleeding, oligomenorrhea, amenorrhea, breakthrough bleeding (26). Kakuno et al. (79) report a higher prevalence of menstrual disturbance only in severe thyroid disease.

In another study done by Singh Pet al.18out of 400 cases, 65% were euthyroid, 26% had hypothyroid, and 9% had hyperthyroidism. The most common type of abnormal uterine bleeding in this study was also menorrhagia followed by polymenorrhoea. In the study carried out by Kattel et al.23 thyroid dysfunction was present in 20% of abnormal uterine bleeding cases out of which 19% had hypothyroidism and 1% had hyperthyroidism. The most common type of abnormal uterine bleeding in this study was menorrhagia followed by metrorrhagia. In the study done by Komathi R et al.24about 30% of abnormal uterine bleeding had thyroid dysfunction out of which 27% had hypothyroid and 3% had hyperthyroidism.

Figure 1. Patterns of abnormal uterine bleeding of patients.

In conjunction with the results being consistent with those of other studies conducted among unexposed women, this strengthens the hypothesis that there is a direct and causal relationship between thyroid hormones and menstrual cycle function. Different patterns of menstrual disorders such as oligomenorrhea, bleeding between cycles, polymenorrhea, hypermenorrhea, and menometrorrhagia have been seen in women with hyperprolactinemia (25). The first line of treatment for hyperprolactinemia is the use of dopamine antagonist (DA) medications, and it has been shown that Cabergoline has been more efficacious than bromocriptine (70, 71). In most patients (approximately 80%), DA induced a normal menstrual cycle with ovulation (72). Rasmussen et al. (73) reported that bromocriptine had no adverse effect on pregnancy outcomes of those women with hyperprolactinemic whose prolactin level and menstruation were normal (13 to 108 months after breastfeeding period). Hypothyroidism alters the length of the menstrual cycle and the volume of bleeding in women of reproductive age.

• We underline the importance of a regular follow up of the pubertal development, including height measurements, thyroid palpation and menstrual anamnesis to intercept red flags findings for hypothyroidism.
• Future studies with larger sample sizes may consider stratifying by age to evaluate whether thyroidal impacts on menstrual cycle function may vary.
• In hyperthyroid patients, they found 42.84 % proliferative, 28.56 % secretory, and 14.28 % hyperplastic endometrium on histopathology examination.
• 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).
• Table 1 summarizes the hormonal changes and results of menstrual disturbances that were observed in various endocrine disorders.

1. Menstrual Cycle Disturbances in Women with Polycystic Ovary Syndrome (PCOS)

Autoimmune conditions potentially related to Hashimoto thyroiditis (such as type I diabetes, coeliac disease, autoimmune gastritis, hypoparathyroidism and Addison disease) were excluded. Hypothyroidism usually presents with unspecific symptoms, as fatigue, weight gain, growth retardation, cold intolerance, constipation 2. The goiter is the most common physical sign, other examination findings include bradycardia, delayed reflexes and myxedema 1. Everlywell offers health and wellness solutions including laboratory testing for wellness monitoring, informational and educational use.

Strengths of the study

Lado-Abeal et al. (28) found that in 45 female patients with CS, only 20% of them had a normal menstrual cycle, while 31.1%, 33.3%, and 8.8% experienced oligomenorrhea, amenorrhea, and polymenorrhea, respectively. Overall in this study, 80% of the participants had menstrual irregularity, a manifestation most closely related to the level of serum cortisol rather than androgen level. The clinical management of this disorder includes steroidogenesis inhibitors, glucocorticoid receptor antagonist, ACTH-lowering agents, and radiation techniques, and bilateral adrenalectomy (86). The literature on CS treatment and improving menstrual cycle irregularity problems is scarce. A 2018 study screened 100 perimenopausal women with a provisional diagnosis of AUB for thyroid dysfunction.

More specifically, a hyperactive thyroid may reduce menstrual bleeding, while an underactive thyroid may lead to a heavier and longer flow. In our patient VWF was assessed quantitatively and qualitatively, with an initial finding of decreased level and activity of the factor, which normalized at the control after one month of substitutive therapy. The patient was consequently diagnosed with autoimmune hypothyroidism and the substitutive therapy with levothyroxine was started at 50 mcg/die, then increased to 100 mcg/die after two weeks. The substitutive therapy with levothyroxine led to the resolution of heavy bleeding after five days and following normalization of coagulative parameters and pituitary hyperplasia. In this study, the most common complaint was menorrhagia which was present in 40.5% of cases.

Onset of thyroid disorders increases with age, and it is estimated that 26% of premenopausal and menopausal women are diagnosed with thyroid disease 4. Thyroid disorders are more common in women than in men and in older adults compared with younger age groups 5. Among women who did not report a history of physician-diagnosed thyroid disease and/or current thyroid medication use, we explored the distribution of each thyroid hormone in univariate analyses and by each covariate stratum. If you’re looking to monitor your thyroid hormone levels, Everlywell offers an easy-to-use, at-home Thyroid Test that can provide all the information you need. Begin by collecting a blood sample, then ship it to one of our certified labs, where your TSH, T3, and T4 levels will be tested.

• No difference in menstrual abnormalities was observed between women with subclinical hypothyroidism and the control group.
• Serum thyroid hormones were measured before the menstrual function study began.
• In the second day of hospitalization, she required a red blood cells transfusion for worsening of anemia (hemoglobin 6,3 g/dl).

According to the current evidence, adolescent and adult females with diabetes may suffer from menstrual cycle irregularity (55, 56). Also, evidence shows the casual relationship between variations in the levels of sex hormones and the risk of type 2 diabetes mellitus (57, 58). The results of the Nurses’ Health study II indicate that women with menstrual cycle length ≥ 40 days are more susceptible to develop diabetes mellitus type 2 (16). Griffin et al. reported that nearly 25% – 30% of women at childbearing age with diabetes suffer from menstrual abnormalities (59). The most common menstrual abnormalities among women with diabetes are secondary amenorrhea and oligomenorrhea (60).

Study population

A thyroid condition can lead to an irregular menstrual cycle due to the hormone imbalance that often coincides. Part of this menstrual irregularity is due to the impact of a thyroid problem on fertility and reproductive health. This study aimed to summarize the menstrual disturbances in different endocrine disorders. On the other hand, prolactin, nicknamed the “milk hormone,” is part of another feedback loop.