Effect of body mass index on pregnancy outcomes in young women with low-prognosis POSEIDON criteria after in vitro fertilization/intracytoplasmic sperm injection.

Abstract

Background: The aim of this study was to investeigate the pregnancy outcomes of young women with low prognosis according to the POSEIDON criteria after IVF/ICSI cycles and to explore the effect of body mass index (BMI) on pregnancy outcomes.

Methods: This was a retrospective cohort study conducted in women who underwent their first IVF/ICSI cycle treatment between January 2018 and December 2020, Among them, these patients who met criteria for POSEIDON group1and 3 were further categorized into four groups according to the China body mass index(BMI) classification, we analyzed the effect of BMI on pregnancy outcomes.

Results: A total of 29,354 patients were conducted first IVF/ICSI cycle between January 2018 and December 2020 in our reproductive center, 5981 women who met the criteria for POSEIDON 1 and POSEIDON 3 were further categorized into four groups according to the China body mass index(BMI) classification. There were not significant differences in the implantation rate and clinical pregnancy rate, regardless of fresh embryo transfer or frozen embryo transfer among the four groups (P > 0.05). The miscarriage rate of fresh embryo transfer was significantly higher in obese patients (P < 0.05), while the live birth rate of fresh embryo transfer and the cumulative live birth rate are significantly lower in obese patients(P < 0.05). BMI was a significant and independent predictor of the miscarriage rate of fresh embryo transfer (adjusted OR 1.111; 95% CI 1.042-1.184; p = 0.001) and the cumulative live-birth rate (adjusted OR 0.937; 95% CI 0.900-0.975; p = 0.001).

Conclusions: Our study indicated that obesity negatively impacts the IVF/ICSI outcomes of young women with low prognosis, including higher miscarriage rate and lower live birth-rate and cumulative live-birth rate. In our study, we found that BMI was the best independent predictor of the miscarriage rate of fresh embryo transfer and cumulative live-birth rate of low-prognosis patients under 35 years old. Thus the best way to reduce these complications for young patients with a poor prognosis was to keep their BMI between 18.5 kg/m² and 24 kg/m².