Donor TSH level is associated with clinical pregnancy among oocyte donation cycles

The purpose of the study is to evaluate the association between donor TSH level (independent of recipient TSH level) and recipient pregnancy outcome among fresh donor oocyte IVF cycles.

This is a retrospective cohort study investigating 232 consecutive fresh donor-recipient cycles (200 total oocyte donors) at an academic medical center. Main outcome measures include clinical pregnancy and live birth.

Cycles were categorized into two groups based on donor TSH level (< 2.5 and ≥ 2.5 mIU/L). After controlling for multiple donor and recipient characteristics, the probability of clinical pregnancy was significantly lower among donors with TSH levels ≥2.5 mIU/L compared to those with TSH values <2.5 mIU/L (43.1 %, 95 % CI 28.5-58.9, versus 66.7 %, 95 % CI 58.6-73.9, respectively, p = 0.01). The difference in live birth rates between the two groups did not achieve statistical significance (43.1 %, 95 % CI 28.8-58.6, versus 58.0 %, 95 % CI 50.0-65.6, respectively, p = 0.09).

Donor TSH level, independent of recipient TSH level, is associated with recipient clinical pregnancy. These findings suggest that thyroid function may impact the likelihood of pregnancy at the level of the oocyte.