AUTHOR=Xue Xia , Shi Wenhao , Zhou Hanying , Tian Li , Zhao Zhenghao , Zhou Dangxia , Shi Juanzi TITLE=Cumulative Live Birth Rates According to Maternal Body Mass Index After First Ovarian Stimulation for in vitro Fertilization: A Single Center Analysis of 14,782 Patients JOURNAL=Frontiers in Endocrinology VOLUME=11 YEAR=2020 URL=https://www.frontiersin.org/journals/endocrinology/articles/10.3389/fendo.2020.00149 DOI=10.3389/fendo.2020.00149 ISSN=1664-2392 ABSTRACT=

Objective: To investigate the cumulative live birth rates (CLBR) according to body mass index (BMI) in women undergoing their first in vitro fertilization (IVF).

Design: Retrospective cohort analysis.

Setting: An IVF clinic in a public hospital.

Patients: This is a retrospective study of 14,782 patients undergoing their first fresh IVF cycles and subsequent frozen embryo transfers in our clinic from January 2014 to January 2017. The follow-up for CLBR continued until January 2019. Patients with a BMI <18.5 kg/m² were considered to be underweight and those with a BMI > 24 kg/m² were considered to be overweight. Patients with a BMI ≥ 28 kg/m² were considered to be obese.

Intervention(s): None.

Primary Outcome Measure: The primary outcome was cumulative live birth rate (CLBR).

Result(s): This study illustrated the “inverted U shape” associations between body weight and IVF outcome (CLBR). The turning points in threshold analysis, as found by an automatic search, were BMIs of 18.5 and 30.4 kg/m². The main finding of this retrospective data analysis is that the CLBR increased in underweight women, plateaued for normal weight and overweight women with a BMI between 18.5 and 30.4 kg/m², and decreased in obese women.

Conclusion(s): The data suggested an “inverted U shape” association between BMI and CLBR. The CLBR increases in underweight women, plateaus in normal weight and overweight women, and then decreases in obese women.