Endocrine Abstracts

Background: Thyroid autoantibodies cross blood-follicle barrier in titer dependent manner and may change oocyte microenvironment with adverse effects on implantation or post-implantation period. Thyroid autoimmunity (TAI) interfers with pregnancy course and newborn anthropometry in pregnancy achieved by assisted reproduction (ART).

Objective: To light upon pregnancy course outcomes and newborn anthropometric characteristics regarding TAI in ART programme.

Methods: The course of clinical pregnancy achieved in 24 women undergoing ART was observed and pregnancy and newborn outcomes compared in two groups divided by the presence of TAI.

Results: In the study population, 33.3% were TAI positive and 66.7% TAI negative women. The special interest was adressed on anti-thyroglobulin antibodies with the important difference in serum, as expected, but in follicular fluid, P < 0.001. Number of retrieved oocyte, number of embryos, top quality and embryo transferred were not significantly different between the groups, but higher percentage of good quality oocytes in TAI negative group were noticed (70.9% vs 81.5%, P = 0.053), without affecting fertilization and implantation rates. Live birth rate was 96.0%, with preterm birth 16.7% and term birth rate 70.8%. Groups were no different comparing the rate of twin pregnancy, early, late miscarriage and preterm birth. Maternal complications, gestational diabetes mellitus or pregnancy induced hypertension, were present in 23.8% with no difference between the groups. In TAI positive group newborns had higher birth weight (P = 0.001) and lenght (P = 0.008). No congenital malformations in newborns were noted.

Conclusions: The study pointed out no adverse effects of TAI on ART achieved pregnancy outcomes, regardless the higher percentage of good quality oocytes in the women without TAI, but TAI could affect newborn anthropometry.