Thyroid Research Thyroid Research Archive Hypothyroidism

The success rate of in vitro fertilization of oocytes is reduced in women with high serum thyrotropin values

(November 2003)

The background of the study. Hypothyroidism may reduce fertility. To determine whether hypothyroidism reduces the rate of success of assisted reproduction, serum thyrotropin (TSH) was measured in a large group of infertile women undergoing this procedure.

How the study was done. Serum TSH was measured in 509 women with infertility who underwent assisted reproduction, consisting of controlled ovarian stimulation, retrieval of oocytes, in vitro fertilization, and transfer of embryos to the woman's uterus. The main outcomes were the frequency of successful oocyte retrieval, fertilization, and implantation; clinical pregnancy; spontaneous abortion; and live birth during the first cycle of treatment.

The results of the study. The causes of infertility were tubal infertility in 118 women (23 percent), male factor infertility in 92 women (18 percent), endometriosis in 74 women (14 percent), ovulatory dysfunction in 54 women (11 percent), and other or unexplained in 171 women (34 percent).

The serum TSH concentrations were similar in the 30 percent of women who became pregnant and the 70 percent who did not. Serum TSH concentrations were higher in the women whose oocytes were not fertilized, but not in the women from whom oocytes were not retrieved, those in whom the embryo did not implant, or those who had spontaneous abortions.

The conclusions of the study. High serum TSH concentrations are associated with decreased in vitro fertilization of oocytes in women with infertility.

The original article. Cramer DW, Sluss PM, Powers RD, McShane P, Ginsburg ES, Hornstein MD, Vitonis AF, Barbieri RL. Serum prolactin and TSH in an in vitro fertilization population: is there a link between fertilization and thyroid function? J Assist Reprod Genet 2003;20:210-5.