Long-term effects of bariatric surgery in women with Polycystic Ovary Syndrome (PCOS), obesity and irregular or absent menstrual periods
| ISRCTN | ISRCTN16272246 |
|---|---|
| DOI | https://doi.org/10.1186/ISRCTN16272246 |
- Submission date
- 05/07/2025
- Registration date
- 20/10/2025
- Last edited
- 20/10/2025
- Recruitment status
- Recruiting
- Overall study status
- Ongoing
- Condition category
- Nutritional, Metabolic, Endocrine
Plain English summary of protocol
Background and study aims
Infertility affects around 1 in 6 couples worldwide. In about 30% of cases, the cause is related to the female partner. One common cause is Polycystic Ovary Syndrome (PCOS), which can lead to irregular or absent periods and problems with ovulation. Obesity can make these symptoms worse. A previous study called the BAMBINI trial showed that weight loss surgery (bariatric surgery) helped women with PCOS and obesity have more regular ovulatory cycles compared to standard medical care. This new follow-up study will look at the long-term effects of that surgery on fertility, metabolism, and quality of life.
Who can participate?
Women who took part in the original BAMBINI clinical trial (https://www.isrctn.com/ISRCTN16668711) may be invited to join this follow-up study.
What does the study involve?
This is an observational study, which means there are no treatments or interventions. Participants will be asked to attend follow-up visits where researchers will collect information about their health, fertility, and well-being over time.
What are the possible benefits and risks of participating?
The main benefit is helping researchers understand how bariatric surgery affects the body in the long term, especially in women with PCOS. There are no significant risks, as this is not a treatment study and no new procedures will be done.
Where is the study run from?
NIHR Imperial Clinical Research Facility at Hammersmith Hospital in London (UK)
When is the study starting and how long is it expected to run for?
April 2025 to September 2026
Who is funding the study?
NIHR Imperial Biomedical Research Centre (UK)
Who is the main contact?
Dr Suhaniya Samarasinghe, suhaniya.samarasinghe@nhs.net
Contact information
Public, Scientific, Principal Investigator
MRC Laboratory of Medical Sciences
Imperial London Hammersmith Campus
London
W12 0HS
United Kingdom
 ORCID ID |
0000-0001-8111-4218 |
|---|---|
| Phone | +44 207 594 5444 |
| suhaniya.samarasinghe@nhs.net |
Study information
| Study design | Single centre observational study |
|---|---|
| Primary study design | Observational |
| Secondary study design | Longitudinal study |
| Study setting(s) | Hospital |
| Study type | Efficacy |
| Participant information sheet | Not available in web format, please use contact details to request a participant information sheet. |
| Scientific title | Bariatric surgery vs. Medical care for obesity and polycystic ovarian syndrome related infertility: Long-term follow-up of the BAMBINI randomised-controlled clinical trial |
| Study acronym | BAMBINI 2.0 |
| Study objectives | To investigate the long-term safety and efficacy of obesity surgery in women with PCOS, obesity and oligomenorrhoea or amenorrhoea |
| Ethics approval(s) |
Not yet submitted, London-Dulwich REC (2 Redman Place, Stratford, London, E20 1JQ, United Kingdom; +44 207 104 8109; dulwich.rec@hra.nhs.uk) |
| Health condition(s) or problem(s) studied | Long-term effects of bariatric surgery in women with Polycystic Ovary Syndrome, obesity and oligomenorrhoea or amenorrhoea. |
| Intervention | This study will invite all participants who took part in the BAMBINI clinical trial (ISRCTN16668711) and received their randomly allocated intervention to attend for a single visit. At this visit, they will have undergo a detailed medical questionnaire, anthropometric measurements, blood tests for reproductive and metabolic hormones, urine pregnancy test, optional adipose tissue biopsy and genetic blood test. |
| Intervention type | Other |
| Primary outcome measure | Number of patient-reported menstrual cycles in the last 12 months |
| Secondary outcome measures | Metabolic outcomes: 1. Body weight is measured using calibrated digital scales at baseline and 1 year 2. Body mass index (BMI) is calculated from measured height and weight at baseline and 1 year 3. Waist circumference is measured using a non-stretchable tape at baseline and 1 year 4. Body composition is measured using dual-energy X-ray absorptiometry (DEXA) at baseline and 1 year 5. Plasma lipid concentration is measured using enzymatic colorimetric assays from a fasting blood sample at baseline and 1 year 6. Plasma liver function tests (ALT, AST, ALP, GGT, bilirubin) are measured using automated clinical chemistry analyzers from a fasting blood sample at baseline and 1 year 7. Plasma HbA1c is measured using high-performance liquid chromatography (HPLC) from a fasting blood sample at baseline and 1 year 8. Plasma fasting glucose is measured using a glucose oxidase method from a fasting blood sample at baseline and 1 year 9. Serum fasting insulin is measured using immunoassay from a fasting blood sample at baseline and 1 year 10. Fasting plasma C-peptide is measured using immunoassay from a fasting blood sample at baseline and 1 year 11. Arterial blood pressure is measured using an automated sphygmomanometer following standard protocols at baseline and 1 year 12. High sensitivity CRP is measured using immunoturbidimetric assay from a fasting blood sample at baseline and 1 year 13. Serum steroid metabolomics is measured using liquid chromatography–mass spectrometry (LC-MS) from a fasting blood sample at baseline and 1 year Reproductive and hormonal outcomes: 14. Pregnancy, miscarriage, and live birth rates are recorded using a structured reproductive history questionnaire at baseline and 1 year 15. Neonatal outcomes are recorded using a structured birth outcome questionnaire at delivery 16. Use of Assisted Reproductive Technology (ART) is recorded using a structured fertility treatment questionnaire at baseline and 1 year 17. Serum LH is measured using immunoassay from a fasting blood sample at baseline and 1 year 18. Serum FSH is measured using immunoassay from a fasting blood sample at baseline and 1 year 19. Serum oestradiol is measured using immunoassay from a fasting blood sample at baseline and 1 year 20. Serum progesterone is measured using immunoassay from a fasting blood sample at baseline and 1 year 21. Serum SHBG is measured using immunoassay from a fasting blood sample at baseline and 1 year 22. Serum testosterone is measured using immunoassay from a fasting blood sample at baseline and 1 year 23. Serum free androgen index is calculated from total testosterone and SHBG at baseline and 1 year 24. Serum androgen profile including androstenedione and DHEAS is measured using immunoassay from a fasting blood sample at baseline and 1 year 25. Serum AMH is measured using immunoassay from a fasting blood sample at baseline and 1 year 26. Salivary progesterone is measured using enzyme immunoassay from a saliva sample at baseline and 1 year 27. Salivary androgens are measured using enzyme immunoassay from a saliva sample at baseline and 1 year 28. A serum/plasma sample is collected and stored for future measurement of novel markers of reproductive or metabolic function (e.g. INSL3) at baseline and 1 year Quality of life: 29. Hospital Anxiety and Depression Scale score is measured using the HADS questionnaire at baseline and 1 year 30. Social functioning is measured using the SF-36 questionnaire at baseline and 1 year 31. PCOS-specific quality of life is measured using the PCOSQ questionnaire at baseline and 1 year 32. Hirsutism is measured using the Ferriman-Gallwey score at baseline and 1 year 33. Female pattern hair loss is measured using the Ludwig visual score at baseline and 1 year 34. Female pattern hair loss is measured using the Savin Alopecia Scale score at baseline and 1 year 35. Acne-related quality of life is measured using the Cardiff Acne Disability Index at baseline and 1 year Other outcomes: 36. Number of medications is recorded using a structured medication inventory at baseline and 1 year Sub-studies: 37. Adipose tissue biology is assessed using subcutaneous adipose tissue biopsy and histological/molecular analysis at baseline and 1 year 38. Genetic analysis is performed using DNA extracted from peripheral blood samples collected at baseline |
| Overall study start date | 24/04/2025 |
| Completion date | 01/09/2026 |
Eligibility
| Participant type(s) | Other |
|---|---|
| Age group | Adult |
| Sex | Female |
| Target number of participants | 76 |
| Key inclusion criteria | Participants from the BAMBINI clinical trial who received their randomly allocated trial intervention. As part of the initial trial, participants gave their consent to be contacted for potential participation in other research studies. |
| Key exclusion criteria | Patients who did not receive their randomly allocated intervention as part of the original BAMBINI clinical trial. |
| Date of first enrolment | 01/09/2025 |
| Date of final enrolment | 02/05/2026 |
Locations
Countries of recruitment
- England
- United Kingdom
Study participating centre
Du Cane Rd
Shepherd's Bush
London
W12 0HS
United Kingdom
Sponsor information
University/education
MRC Laboratory of Medical Sciences
London
W12 0HS
England
United Kingdom
| Phone | +44 (0)20 7594 9456 |
|---|---|
| rgit@imperial.ac.uk | |
| Website | https://imperialbrc.nihr.ac.uk/ |
"ROR" |
https://ror.org/01kmhx639 |
Funders
Funder type
Government
Private sector organisation / Research institutes and centers
- Alternative name(s)
- NIHR Imperial BRC, Imperial Biomedical Research Centre, BRC
- Location
- United Kingdom
Results and Publications
| Intention to publish date | 01/02/2027 |
|---|---|
| Individual participant data (IPD) Intention to share | Yes |
| IPD sharing plan summary | Published as a supplement to the results publication |
| Publication and dissemination plan | The results are likely to be published within the 12 months following the study in peer-reviewed journals and websites, and presented in medical conferences. Participant confidentiality will be ensured at all times and they will not be identified in any publication as these will be anonymised. A lay summary of the key results from the study will be written and sent and/or presented to them. |
| IPD sharing plan | All data generated or analysed during this study will be included in the subsequent results publication. |
Editorial Notes
20/10/2025: Trial's existence confirmed by the National Institute for Health and Care Research (NIHR) (UK).
