Pre-pregnancy body mass index does not impact live birth rate
after frozen-thawed euploid embryo transfer: a retrospective cohort
study
Xitong Liu,a Li Tian,a He
Cai,a Juanzi Shi, a Haiyan Bai,a
a The Assisted Reproduction Center, Northwest Women’s
and Children’s Hospital, Xi’an, China
Correspondence: Haiyan Bai, The Assisted Reproduction Center,
Northwest women’s and Children’s Hospital, Xi’an, China.
Email: flyindance29578@qq.com
ObjectiveTo assess the effects body mass index (BMI) on live birth rates in
patients undergoing in vitro fertilization (IVF) with trophectoderm
biopsy and preimplantation genetic testing for aneuploidies (PGT-A) when
transferring a single euploid blastocyst.
Design Retrospective cohort study.
Setting Public fertility center in China.
Population 821 women who underwent first cycle of frozen-thawed
single euploid blastocyst transfer between 2012 and 2020.
Methods Patients were grouped by World Health Organization
(WHO) BMI class: underweight (<18.5, n=80), normal weight
(18.5-24.9, n=602), overweight (25-30, n=112), and obese (≥30, n=27). A
logistic regression model was used to assess the association between BMI
and live birth while adjusting for potential confounders.
Main outcome measures Live-birth rate was primary outcome.
Results There was no difference in the birth weight,
miscarriage, preterm birth, pregnancy complication, type of delivery and
fetal gender by BMI category. The clinical pregnancy rate was higher in
the overweight and obese groups. In multivariate logistic regression
analysis, we fail to demonstrate a statistically significant
relationship between BMI and live birth in underweight (adjusted odds
ratio [AOR] 0.80; 95% confidence interval [CI], 0.47-1.35,
p=0.402), overweight (AOR 0.85; 95% CI, 0.54-1.35, p=0.491) or obese
(AOR 1.07; 95% CI, 0.48-2.38, p=0.864) patients compared with the
normal weight reference group.
Conclusion No statistically significant relationship was
identified between BMI and live birth in patients undergoing IVF with
PGT-A, suggesting that the negative impact of obesity on IVF and
clinical outcomes may be related to aneuploidy.
Keywords body mass index (BMI), euploid, live birth rate
Tweetable abstract In women undergoing IVF with PGT-A, BMI does
not influence live birth.