Subclinical hypothyroidism and thyroid autoimmunity in recurrent pregnancy loss: a systematic review and meta-analysis

Subclinical hypothyroidism does not appear to be associated with recurrent pregnancy loss but thyroid autoimmunity does. Levothyroxine does not appear to benefit euthyroid, thyroid antibody-positive women with recurrent pregnancy loss.

Like Comment
Related Content

Volume 113, Issue 3, Pages 587–600.e1

Authors:

Allan C. Dong, M.D., Jessica Morgan, M.D., Monica Kane, M.P.H., Alex Stagnaro-Green, M.D., M.H.P.E., M.H.A., Mary D. Stephenson, M.D., M.Sc.

Abstract:

Objective

To determine whether overt/subclinical hypothyroidism and/or thyroid autoimmunity is associated with recurrent pregnancy loss (RPL) and whether treatment improves outcomes.

Design

Systematic review and meta-analysis.

Setting

University obstetrics and gynecology departments.

Patient(s)

Women with RPL and overt/subclinical hypothyroidism, and/or thyroid autoimmunity.

Intervention(s)

None.

Main Outcome Measure(s)

Associations between RPL and overt/subclinical hypothyroidism and/or thyroid autoimmunity and any effects of treatment.

Result(s)

After our review of articles from PubMed, EMBASE, Web of Science, and CENTRAL, we found two interventional studies in which levothyroxine did not improve the subsequent live-birth rate in women with subclinical hypothyroidism with or without thyroid antibodies. A meta-analysis of five studies revealed the prevalence of subclinical hypothyroidism in RPL to be 12.9% (95% confidence interval [CI], 0%–35.2%). A meta-analysis of 17 studies revealed a statistically significant association between RPL and thyroid autoimmunity (odds ratio 1.94; 95% CI, 1.43–2.64). However, a randomized study suggested that levothyroxine does not benefit euthyroid women with thyroid autoimmunity.

Conclusion(s)

Based on the limited observational studies available, no association exists between RPL and subclinical hypothyroidism, nor does levothyroxine improve subsequent pregnancy outcomes. An association exists between RPL and thyroid autoimmunity, but levothyroxine does not improve subsequent pregnancy outcomes. Women with RPL should be screened/treated for overt thyroid disease but not thyroid autoimmunity. Thyroid antibody screening is not supported by the published studies, and further randomized studies are needed. No recommendation regarding the treatment of subclinical hypothyroidism can be made at this time; prospective and randomized studies are urgently needed.



Read the full text here.

Fertility and Sterility

Editorial Office, American Society for Reproductive Medicine

Fertility and Sterility® is an international journal for obstetricians, gynecologists, reproductive endocrinologists, urologists, basic scientists and others who treat and investigate problems of infertility and human reproductive disorders. The journal publishes juried original scientific articles in clinical and laboratory research relevant to reproductive endocrinology, urology, andrology, physiology, immunology, genetics, contraception, and menopause. Fertility and Sterility® encourages and supports meaningful basic and clinical research, and facilitates and promotes excellence in professional education, in the field of reproductive medicine.

No comments yet.