IMPACT OF ELEVATED BODY MASS INDEX (BMI) ON FEMALE FERTILITY AND REPRODUCTIVE OUTCOMES
Abstract
Elevated body mass index (BMI) is increasingly prevalent among women of reproductive age and has been associated with adverse reproductive outcomes. This study aimed to synthesize original observational cohort and registry-based evidence examining the impact of elevated BMI on female fertility, assisted reproductive technology (ART) outcomes, and pregnancy outcomes. Methods: A structured literature-based synthesis was conducted using PubMed, Scopus, and Web of Science. Only original cohort and registry studies reporting empirical patient-level data were included. Outcomes assessed included live birth rate, clinical pregnancy rate, implantation rate, fertilization rate, miscarriage risk, gonadotropin dose requirement, embryo quality, and obstetric complications. Results: Fifteen original cohort and national registry studies were included, representing data from multiple countries. Elevated BMI was consistently associated with reduced live birth rates (approximately 10–30% lower), decreased clinical pregnancy and implantation rates, and increased miscarriage risk (1.3–2.0-fold higher). Higher BMI was also linked to increased gonadotropin requirements and greater obstetric complications. Large registry datasets demonstrated a clear dose–response relationship, with progressively worse outcomes across increasing BMI categories. Conclusion: Elevated BMI is a significant and modifiable risk factor for impaired reproductive outcomes. Preconception weight optimization may improve fertility and ART success while reducing pregnancy-related complications.
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