The Relationship Between Obesity, Bariatric Surgery, and Infertility: A Systematic Review

Abstract

Background: Obesity is a complicated, chronic condition that has a major impact on reproductive health, leading to infertility, anovulation, and poor pregnancy outcomes. It alters the hypothalamic-pituitary-ovarian (HPO) axis, promotes insulin resistance, and causes persistent low-grade inflammation, all of which result in hormonal abnormalities that compromise normal ovarian function. Because standard weight loss procedures frequently fail to provide significant and long-term reproductive benefits, bariatric surgery is becoming increasingly popular as a therapeutic option for obese women trying to conceive. However, continuous research is being conducted to determine the degree of its advantages and potential hazards to fertility and pregnancy outcomes.

Methods: This systematic review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) standards and entered into the PROSPERO database. Comprehensive searches in the PubMed, Scopus, and Web of Science databases turned up relevant studies. Studies that examined the effects of bariatric surgery on female fertility, ovulatory function, pregnancy rates, and neonatal outcomes were considered. Methodological quality and risk of bias were evaluated using the Newcastle-Ottawa Scale (NOS) for observational studies and the Cochrane Risk of Bias Tool for randomized controlled trials.

Results: This review comprised 34 studies. More than 75% of the studies analyzed showed improvements in ovulatory function, monthly regularity, or spontaneous pregnancy after bariatric surgery. Post-surgical pregnancies are related to a lower incidence of gestational diabetes, hypertension, and macrosomia. However, several studies raised concerns about nutritional inadequacies and the possibility of small-for-gestational-age newborns, particularly following Roux-en-Y gastric bypass. Studies suggest delaying conception for 12 to 18 months after surgery to reduce nutritional hazards and improve pregnancy outcomes. Variability in study design, follow-up duration, and surgical methods reduces the generalizability of findings, emphasizing the importance of uniform research protocols.

Conclusions: Bariatric surgery is a highly effective treatment for increasing fertility and pregnancy outcomes in obese women, particularly those with PCOS. However, rigorous preconception planning, postoperative nutritional monitoring, and multidisciplinary follow-up are required to reduce the related hazards. Future research should concentrate on long-term reproductive outcomes, standardizing fertility assessment criteria, and improving clinical guidelines for managing post-bariatric pregnancies. These findings support the incorporation of bariatric surgery into fertility treatment regimens for obese women, and they may shape future revisions to clinical guidelines on reproductive care following weight loss surgery.

Keywords: bariatric surgery; infertility; metabolic syndrome; obesity; ovulatory dysfunction; polycystic ovarian syndrome (PCOS); pregnancy outcomes; reproductive health.

Figure 1

PRISMA Flow Diagram of Study Selection Process.