Effectiveness of in vitro fertilization for infertility in women with euthyroid status

Abstract

The influence of thyroid hormone (TSH) on the probability of pregnancy is a controversial issue in modern scientific literature, since impressive scientific data has been published lately questioning previously undoubtful fact that preconception levels of TSH must be decreased to target values not exceeding 2.5 mIU/l.The aim of the research was to investigate the influence of elevation of TSH in the range of 2.5–4.0 mIU/l in women on the outcomes of in-vitro fertilization (IVF) procedures by analyzing the parameters of controlled ovarian stimulation (COS) and embryological indicators of its efficacy, as well as the percentage of pregnancy and reproductive losses.The work was based in “Centre for Reproductive Medicine”. The study included 195 married couples that under- went IVF due to infertility. Two groups were formed: Group 1 consisted of 94 women with pre-IVF TSH ranging between 2.5–4.2 mIU/l, while Group 2 included 101 women with the initial level of TSH before the beginning of ovarian stimulation less than 2.5 mIU/l.It was established that in women with TSH ranging between 2.5–4.2 mIU/l with normal levels of free thyroxine, embryological parameters of COS efficiency showed comparable results of follicle growth, oocyte maturation, percentage of blastocyst formation in both groups. The efficiency of in vitro fertilization was found to be independent of the preconception TSH level if this index was in the range of 2.5–4.2 mIU/l: comparable incidence of pregnancy (60.64 and 51.49 %; p = 0.254), incidence of spontaneous abortion in the 1st trimester (15.79 and 9.62 %; p = 0.500), incidence of late spontaneous miscarriage at gestational age 12–22 weeks (3.51 and 11.54 %; p = 0.709 were observed).