Bariatric surgery for spontaneous ovulation in women living with polycystic ovary syndrome: the BAMBINI multicentre, open-label, randomised controlled trial.
Level 2 - randomized trial
Individual multicentre randomized controlled trial
PubMed 38782004 · doi:10.1016/S0140-6736(24)00538-5
What was done
In a multicentre, open-label randomized controlled trial (BAMBINI), 80 women aged >18 years with polycystic ovary syndrome (PCOS), oligomenorrhoea or amenorrhoea, and BMI ≥35 kg/m² were randomly allocated (1:1) to vertical sleeve gastrectomy (n=40) or medical and behavioral management (n=40). The primary outcome was the total number of biochemically confirmed ovulatory events over 52 weeks, determined via weekly serum progesterone measurements analysed on an intention-to-treat basis.
What was found
Over 52 weeks, the median number of confirmed ovulations was 6 (IQR 3.5–10.0) in the surgical group versus 2 (IQR 0.0–4.0) in the medical group. Surgical intervention yielded 2.5 times more spontaneous ovulations than medical therapy (incidence rate ratio 2.5, 95% CI 1.5–4.2; p < 0.0007). Adverse events occurred more frequently in the surgical group (24 events [66.7%]) than in the medical group (12 events [30.0%]), though without long-term sequelae or treatment-related deaths.
Why it matters
This is the first randomized trial demonstrating that bariatric surgery substantially improves spontaneous ovulation rates compared to medical and behavioral lifestyle therapy in women with PCOS and severe obesity, supporting its potential role in restoring ovulatory function.
Limits
The trial had a small sample size (n=80), an open-label design, and notable attrition (10 dropouts in surgery, 7 in medical care). The population was predominantly White (79%), limiting generalizability, and the primary endpoint tracked biochemical ovulation rather than clinical pregnancy or live birth rates.
Cited by
- supports PCOS is the number one cause of anovulatory infertility globally.