To review the menstrual function and fertility in thyroid disease, mainly in hyperthyroidism and hypothyroidism. Also to register the consequences of (131)I therapy, which is used widely in the treatment of Graves' disease and thyroid cancer, on subsequent pregnancies and on fertility in these patients.
Design
A MEDLINE computer search was used to identify relevant studies. The type of menstrual disturbances and the status of fertility were recorded from all the studies found. Also, the fertility and genetic hazard of female patients with Graves' disease and thyroid cancer who were treated with (131)I were registered.
RESULT(S): Both hyperthyroidism and hypothyroidism may result in menstrual disturbances. Menstrual abnormalities are less common now than in previous series. In a recent study, we found that only 21.5% of 214 thyrotoxic patients had some type of menstrual disturbance, compared to 50 to 60% in some older series. The most common manifestations are hypomenorrhea and oligomenorrhea. According to the results of endometrial biopsies, most thyrotoxic women remain ovulatory. Moreover, the genetic hazard incident to radioiodine therapy in Graves' disease and thyroid carcinoma is very small; exposure to (131)I does not cause reduced fecundity, and the risk of loss of fertility is not a contraindication for its use in these patients. mIn hypothyroidism, the frequency of menstrual irregularities has very recently been reported to be 23.4% among 171 hypothyroid patients studied. This is much less than that reported in previous studies, which showed that 50 to 70% of hypothyroid female patients had menstrual abnormalities. The most common manifestation is oligomenorrhea. Severe hypothyroidism is commonly associated with failure of ovulation. Ovulation and conception can occur in mild hypothyroidism. These pregnancies are, however, often associated with abortions, stillbirths, or prematurity. The latter may be of greater clinical importance in infertile women with unexplained infertility.
CONCLUSION(S): These new data, mainly concerning menstrual abnormalities in hyperthyroidism and hypothyroidism, are inconsistent with what is generally believed and written in the classic thyroid textbooks and indicate that such opinions should be revised.
PMID 11119728 11119728 DOI 10.1016/s0015-0282(00)01589-2 10.1016/s0015-0282(00)01589-2
Cite this article
Krassas, G. E. (2000). Thyroid disease and female reproduction. Fertility and sterility, 74(6), 1063-1070. https://doi.org/10.1016/s0015-0282(00)01589-2
Thyroid disease in general, and hypothyroidism in particular, are very common in women. In the USA, the most common cause of primary thyroid deficiency is on an autoimmune basis due to lymphocytic (Hashimoto) thyroiditis. Because there are thyroid hormone receptors in virtually every tissue of the body, the manifestations of hypothyroidism are varied, but problems with abnormal menses, conception, fertility, and pregnancy can be especially troubling in young women. The single most important diagnostic test is measurement of serum thyrotropin (TSH). The overwhelming majority of patients with hypothyroidism are treated with a single daily dose of synthetic levothyroxine with the goal of therapy being restoration of a normal metabolic state with return of the TSH level down to the range of 0.5 to 1.5 mlU/L. "Subclinical" hypothyroidism refers to those patients with early or mild thyroid hypofunction manifested as slight elevations of thyrotropin (approximately 4-10 mlU/L) although serum thyroxine (T4) and triiodothyronine (T3) levels are within their reference ranges. The entity is somewhat controversial in regard to its consequences if left untreated, and whether or not we should be screening patients, at least susceptible populations, for the condition. Reports indicate an association between subclinical hypothyroidism and poor outcomes of pregnancy, as well as dyslipidemias, atherogenesis, and increased mortality in the long term. We believe these consequences are sufficiently compelling to warrant screening and treatment with levothyroxine when found to halt progression to overt hypothyroidism, and improve symptoms, pregnancy outcomes, lipid abnormalities, and cardiovascular function. Obstetricians & Gynecologists, Family Physicians. After completion of this article, the reader should be able to recall that hypothyroidism is a common disease in women, has many protean manifestations, and can be successfully diagnosed and treated; explain that the condition of subclinical hypothyroidism can be diagnosed and if treated can prevent many untoward complications; and state that there should be heightened awareness of the disease so that proper screening tests can be performed.
Practice Committee of the American Society for Reproductive Medicine, 2026·Fertility and Sterility
Current strategies for the assessment and treatment of recurrent pregnancy loss are discussed. This replaces the previous document, titled, "Evaluation and treatment a committee opinion," last published in 2012.
This narrative review examines the evidence for medical optimization of inflammatory conditions, vitamin deficiencies, endocrine disorders, immune dysregulation, oligo-ovulation, and luteal phase factors to improve fertility outcomes in women attempting to conceive through natural or timed intercourse. Overall, there is a paucity of data with respect to these categories among patients pursuing timed intercourse, precluding our ability to draw strong recommendations. However, there is strong evidence supporting treatment of endocrine disorders, specifically overt thyroid dysfunction and hyperprolactinemia, as well as oligo-ovulation. Conversely, treatment of subclinical hypothyroidism is not recommended. The current data are insufficient to support empiric use of antiinflammatory medications, corticosteroids, thyroid hormones, or vitamins or supplements to improve chances of pregnancy in a general infertility population.
Restorative Reproductive Medicine (RRM) aims to restore fertility by diagnosing and treating the underlying causes of infertility. RRM is frequently promoted as an alternative to assisted reproductive technology (ART), despite uncertainty regarding its comparative effectiveness and safety. Where delayed childbearing and infertility are becoming more common, reliance on optimization of natural physiology alone may delay effective treatment and compromise reproductive outcomes. A systematic review of the current evidence comparing RRM to either ART or unassisted conception is, therefore, essential to inform clinical practice, guideline development, and shared decision-making for patients experiencing infertility. To assess the effectiveness and safety of RRM approaches, evaluated as a whole, rather than as individual components, compared with ART and medically unassisted conception in couples experiencing infertility. A systematic literature search of MEDLINE, Embase, CENTRAL and the Journal of Restorative Reproductive Medicine from inception to 28 November 2025. We included randomized control trials (RCTs) or nonrandomized comparative studies evaluating reproductive and safety outcomes of RRM as a unified treatment, compared with either ART or expectant management (attempted medically unassisted conception). Two reviewers independently screened titles, abstracts and full texts with disagreements resolved by a third reviewer. We retrieved 724 records, of which 16 studies underwent full-text review. No RCTs or comparative observational studies were identified. All 16 full-text studies were excluded for an ineligible study design (no control group); most were cohort studies in which all participants underwent RRM. Ten studies reported reproductive outcomes; nine of these made claims regarding the benefits or effectiveness of RRM. None of these claims were supported by the study designs used, as the lack of a comparison group precludes reliable estimation of treatment effects. Consequently, these studies cannot provide valid estimates of RRM success rates, nor permit any meaningful inference about its effectiveness relative to unassisted conception or ART. Large-scale RCTs or prospective cohort studies reporting effectiveness and safety outcomes are required to inform evidence-based fertility guidelines. There are no comparative studies to support reliable estimates of the safety and effectiveness of RRM compared with ART or medically unassisted conception for couples experiencing infertility.