Impact of Bariatric Surgery on Female Sexual Function and Sex Hormones

BACKGROUND:

Obesity is associated with significant physiological and psychological morbidity. While the metabolic effects of bariatric surgery are well-documented, its impact on female sexual health remains understudied, particularly in Middle Eastern populations. Sexual function is regulated by complex interactions between sex hormones (estrogen, testosterone, SHBG), psychological status (depression, anxiety), and body image. Obesity disrupts the hypothalamic-pituitary-gonadal axis through increased aromatase activity in adipose tissue, leading to hormonal imbalances. Weight loss following bariatric surgery may restore hormonal homeostasis and improve psychological well-being, potentially enhancing sexual function. However, the mediating pathways linking these changes have not been systematically examined.

OBJECTIVES:

Primary: To assess changes in female sexual function (FSFI scores) and sex hormone levels (total testosterone, free testosterone, estradiol E2, SHBG, and calculated Free Androgen Index) from baseline to 6 months after bariatric surgery.

Secondary: (1) To assess changes in depressive symptoms (Beck Depression Inventory-II) and anxiety symptoms (Beck Anxiety Inventory); (2) To assess changes in quality of life (Bariatric Quality of Life Index); (3) To assess body image satisfaction at 6 months; (4) To assess changes in partner sexual function (International Index of Erectile Function); (5) To explore mediating pathways linking weight loss, hormonal changes, mood improvement, and sexual function improvement;

METHODS:

Design: Prospective single-center observational cohort study. Setting: Department of General Surgery (Bariatric Surgery Unit), Kasr Al-Ainy Faculty of Medicine, Cairo University, Egypt.

Population: 40 morbidly obese female patients aged 18-45 years with stable, sexually active partner relationships, scheduled for primary bariatric surgery (sleeve gastrectomy or gastric bypass).

Procedures:

Eligible participants provide informed consent at baseline. Assessments occur at two time points: pre-operatively (within 2 weeks before surgery) and 6 months post-operatively.

At each assessment, participants undergo:

• Clinical evaluation: height, weight, BMI, smoking history, marital status, menstrual history (cycle regularity, last menstrual period), medication review
• Psychometric assessments:

• Arabic Female Sexual Function Index (ArFSFI) - 19 items, 6 domains
• Beck Depression Inventory-II (BDI-II) - 21 items
• Beck Anxiety Inventory (BAI) - 21 items
• Bariatric Quality of Life Index (BQL) - 30 items
• Post-bariatric body image satisfaction questionnaire (6 months only)
• Hormonal assessment: Fasting morning blood sample (8:00-11:00 AM) during luteal phase for measurement of total testosterone, free testosterone, estradiol E2, and SHBG using electrochemiluminescence immunoassay. Free Androgen Index (FAI) is calculated as (total testosterone [nmol/L] × 100)/SHBG [nmol/L].
• Partner assessment: International Index of Erectile Function (IIEF) completed by partner

Significance:

This study will provide comprehensive, mechanistic insights into the multi-dimensional improvements in female sexual health following bariatric surgery. By including hormonal, psychological, and partner assessments, it addresses critical gaps in the literature and provides culturally-relevant data for Middle Eastern populations. Findings may inform pre-operative counseling and post-operative care for women undergoing bariatric surgery.

Inclusion criteria

• Female gender
• Age 18-45 years (childbearing period)
• Body Mass Index (BMI) ≥40 kg/m² or ≥35 kg/m² with obesity-related comorbidities, meeting international criteria for bariatric surgery
• Scheduled for primary bariatric surgery (sleeve gastrectomy or Roux-en-Y gastric bypass)
• Presence of a stable, sexually active intimate partner relationship
• Sexually active
• Willingness to participate and provide informed consent
• Ability to complete Arabic-language questionnaires

Exclusion criteria

• Women who are not sexually active
• Post-menopausal women (amenorrhea ≥12 months without other cause)
• Current pregnancy or lactation
• History of medication use that can interfere with sexual function, including:
• Antidepressants
• Antipsychotics/psychotropic drugs
• Beta-blockers
• Spironolactone
• Hormonal contraceptives (unless stable for ≥3 months and continued throughout study)
• Hormone replacement therapy
• Major uncontrolled medical conditions:
• Chronic heavy smoker (smoking index ≥400 pack-years)
• History of pelvic floor surgery or gynecological malignancy
• Partner with known erectile dysfunction or use of erectile dysfunction medications
• Previous bariatric surgery (revisional procedures)
• Inability or unwillingness to provide informed consent