When Weight Matters: How Obesity Impacts Reproductive Health and Pregnancy-A Systematic Review.

Purpose of review: This systematic review evaluates the impact of obesity on both male and female reproductive health, assisted reproductive technology (ART) outcomes, and pregnancy-related complications, providing a comprehensive synthesis of the evidence.

Recent findings: Obesity is a critical factor adversely affecting reproductive health, ART success rates, and pregnancy outcomes. Recent studies indicate hormonal disruptions, metabolic syndrome, and epigenetic modifications as central mechanisms linking obesity to infertility and adverse pregnancy results. A systematic search adhering to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines included 35 studies, focusing on obesity-related reproductive outcomes. The review highlights that obesity disrupts hormonal balance, including reductions in sex hormone-binding globulin (SHBG) and testosterone levels, alongside increased insulin resistance and chronic inflammation. These mechanisms impair ovarian function, endometrial receptivity, and sperm quality, resulting in prolonged time-to-pregnancy (TTP), reduced ART success rates, and increased miscarriage risk. During pregnancy, maternal obesity elevates risks of gestational diabetes mellitus (GDM), preeclampsia, and cesarean delivery while contributing to neonatal complications, such as macrosomia and neonatal intensive care unit (NICU) admissions. The findings emphasize the dual impact of maternal and paternal obesity on offspring health, particularly through epigenetic modifications leading to intergenerational metabolic dysfunction. This review underscores the necessity of preconception weight management, individualized ART protocols, and tailored antenatal care to mitigate obesity's adverse effects on reproductive outcomes. Future research should focus on understanding male infertility mechanisms, optimizing ART interventions for individuals with obesity, and conducting longitudinal studies on the intergenerational impacts of obesity on reproductive health. This synthesis provides actionable insights to guide clinical practices and future investigations.