Endocrine Abstracts

Introduction: The role of thyroxine (T₄) during embryo development is recognised as crucial. The research question of this study was if embryo quality and reproductive outcomes after IVF are affected by maternal thyroid function and/or thyroid auto-immunity (TAI).

Methods/design: We conducted a prospective study (ThyrART), assessing embryo quality and reproductive outcome of women undergoing ovarian stimulation with a flexible GnRH-antagonist protocol for IVF (classic or ICSI), whose thyroid function (TSH, fT₃, and fT₄) and TAI (anti-TPO and anti-Tg) were closely observed. Embryo quality scores were calculated and reproductive outcomes were recorded.

Results: Best embryo score at day 2 was positively correlated with the overall change of fT₄ concentrations (r=0.64, P=0.048). Biochemical pregnancy and live birth rates were negatively correlated with overall change of TSH concentrations (r=−0.741, P=0.004 and r=−0.534, P=0.06 respectively).

Conclusion: The facts that changes in maternal TSH concentrations are associated with pregnancy outcomes and that changes in thyroid hormones are associated with embryo parameters need further confirmation. Interventional studies in women undergoing ovarian stimulation for IVF are needed to demonstrate a possible positive influence of levo-thyroxine supplementation, in selected cases, on their reproductive outcomes.

Disclosure: This work was supported by Hellenic Endocrine Society (research grant).