INTRODUCTION
The overweight and obesity epidemic continues to plague modern society
due to the radical change of lifestyle and decreased physical exercise
in recent years. Research has demonstrated that overweight and obesity
are major causes of chronic diseases, such as cardiovascular disease and
type 2 diabetes1. Obesity raises the risk of
hypertension, dyslipidemia, diabetes, and coronary heart disease.
The burden of overweight and obesity is high in both developed and
developing countries, with the proportion of overweight and obese women
increasing from 29.8% in 1980 to 38.0% in 20132.
Elevated body mass index (BMI) in women affects every stage of
reproductive life, including puberty, pregnancy, and delivery. This is
related to menstrual and ovulatory disorders, impaired endometrial
development and embryo implantation, increased abortion rates, and
pregnancy complications, such as hypertensive disorders of pregnancy
(HDP), pre-eclampsia, gestational diabetes mellitus (GDM), postpartum
hemorrhage, and cesarean delivery3. Moreover, adverse
perinatal outcomes, including fetal macrosomia and neural tube defects,
are more likely to occur in obese women4.
Numerous studies investigating the impact of elevated BMI on in-vitro
fertilization (IVF)/intracytoplasmic sperm injection (ICSI) outcomes
have been published, albeit with disparate results. Several studies
found that an elevated BMI had no adverse effect on IVF/ICSI
outcomes5-8, while others demonstrated that elevated
BMI was associated with adverse IVF outcomes, including lower ovarian
response, inferior oocyte and embryo quality, higher cancellation rate,
and lower clinical pregnancy rate (CPR) and LBR, as well as higher rate
of miscarriages9-16. Despite the broad research in
this area, the effect of elevated BMI on IVF/ICSI outcomes is
indeterminate.
Therefore, the aim of this study was to evaluate the impact of elevated
BMI on both short- and long-term outcomes of fresh IVF/ICSI cycles and
subsequent frozen embryo transfer (FET) cycles, particularly ovarian
response, embryo quality, pregnancy outcomes, obstetric and neonatal
complications, and congenital defects. This way, the impact of high BMI
on assisted reproductive technology (ART) can be elucidated more
comprehensively and inform pre-ART counseling of overweight and obese
women.