AUTHOR=Qu Pengfei , Mi Yang , Zhao Doudou , Wang Min , Dang Shaonong , Shi Wenhao , Shi Juanzi 

TITLE=Effect of the Interaction Between Pre-pregnancy Body Mass Index and Fresh/Frozen Embryo Transfer on Perinatal Outcomes of Assisted Reproductive Technology-Conceived Singletons: A Retrospective Cohort Study

JOURNAL=Frontiers in Endocrinology

VOLUME=11

YEAR=2020

URL=https://www.frontiersin.org/journals/endocrinology/articles/10.3389/fendo.2020.560103

DOI=10.3389/fendo.2020.560103

ISSN=1664-2392

ABSTRACT=<p><bold>Objective:</bold> To demonstrate the association between pre-pregnancy maternal overweight, obesity, and perinatal outcomes of singletons conceived by assisted reproductive technology (ART).</p><p><bold>Design:</bold> Retrospective cohort study from 2006 to 2015 data from a single ART center.</p><p><bold>Setting:</bold> Assisted Reproduction Center, Northwest Women's and Children's Hospital, Xi'an, Northwestern China.</p><p><bold>Patients:</bold> We included 7,818 women undergoing ART and their singleton infants.</p><p><bold>Interventions:</bold> None.</p><p><bold>Main Outcome Measure:</bold> The primary outcome measures were preterm birth (PTB), macrosomia, low birth weight, small for gestational age, and large for gestational age (LGA).</p><p><bold>Results:</bold> We experienced an increase in the risk of PTB, macrosomia, and LGA in overweight and obese groups compared with that in normal-weight groups [PTB: overweight vs. normal weight: odds ratio [OR] = 1.44, 95% CI: 1.18–1.75; obesity vs. normal weight: OR = 1.53, 95% CI: 1.04–2.25; macrosomia: overweight vs. normal weight: OR = 1.78, 95% CI: 1.48–2.14; obesity vs. normal weight: OR = 2.16, 95% CI: 1.52–3.06; LGA: overweight vs. normal weight: OR = 1.63, 95% CI: 1.39–1.90; obesity vs. normal weight: OR = 2.11, 95% CI: 1.57–2.83]. We observed a significant interaction between maternal BMI and fresh/frozen embryo transfer on PTB and LGA (<italic>P</italic> = 0.030; <italic>P</italic> = 0.030). Fresh embryo transfer significantly increased the effect of maternal BMI on LGA (fresh: OR = 1.14, 95% CI: 1.10–1.18; frozen: OR = 1.09, 95% CI: 1.04–1.13), and frozen embryo transfer increased the effect of maternal BMI on PTB (fresh: OR = 1.03, 95% CI: 0.99–1.08; frozen: OR = 1.09, 95% CI: 1.04–1.15).</p><p><bold>Conclusions:</bold> Pre-pregnancy maternal overweight and obesity were associated with higher risks of PTB, macrosomia, and LGA in ART-conceived singletons. These associations were affected by the timing of embryo transfer (fresh/frozen embryo transfer). Therefore, we recommend women before ART to maintain a normal BMI for the prevention of adverse perinatal outcomes.</p>