Neonatal outcome after fresh versus frozen embryo transfer in normogonadotropic healthy young women undergoing IV

A. Virginaş, B. Cârstea, S. Koszeghi, I.B. Nagy, Z. Virginas, T. Korosi, G. Vajta

Rezumat: Purpose. To assess if the frozen-thawed embryo transfer (FET) results in better birth outcomes than fresh embryo transfer (ET). Methodology. Our retrospective study involved women undergoing in vitro fertilization (IVF) between 2017 and 2019 using autologous eggs and having a singleton pregnancy delivered from the 37th week onward at an IVF centre in Târgu-Mureş. The study included 121 and 95 patients with fresh and frozen embryo transfer, respectively. Furthermore, patients with normal BMI, non-smokers and aged under 40 years old were included. We compared the rates of mean birth weight, low birth weight (LBW <2.5 kg) and high birth weight (HBW>4 kg), after fresh versus frozen embryo transfer in normogonadotropic healthy young women undergoing IVF. Results. The mean neonatal birth weight was higher after FET than after ET (3316 g FET versus 3154 g ET). The result of the trial suggested that the FET protocol was associated with significantly lower rates of LBW (16.8% FET versus 21.4% ET; p<0.05) and with higher rates of macrosomia (5.2% FET versus 0.8% ET; p<0.03) than the fresh ET protocol. The assessment of 216 babies showed no statistically significant difference in the mode of delivery (C-section versus vaginal birth) and sex of live born between the two study groups. Conclusions. The risk of high birth weight following frozen/thawed embryo transfer was greater than that following fresh embryo transfer, but the risk of low birth weight among frozen/thawed embryo transfer neonates was significantly decreased in comparison with fresh embryo transfer neonates.
Cuvinte cheie: frozen thawed embryo transfer, fresh embryo transfer, neonatal outcome, young women.