Tests vitamin D against a placebo in women with polycystic ovary syndrome
Tests vitamin D supplements in women with polycystic ovary syndrome to see effects on ovulation.
Key facts
- Who runs it
- The University of Hong Kong
- Where
- Hong Kong, Hong KongSee the 3 sites
- Trial code
- Registry title
- Effect of Vitamin D on Ovulation Rate in Women With Polycystic Ovary Syndrome
- Status
- Recruiting
- People taking part
- 220 people, planned
- Started
- 26 Jan 2021
- Expected to end
- 31 Dec 2026
- Type of study
- Interventional, 2 groupsOne group gets an existing treatment, for comparison.
- Treatments tested
- Vitamin D
- Placebo
- Record updated
- 14 May 2024
Who can take part
AI summary
From the trial's eligibility criteria. Machine-read from the registry text on this page, so it can be wrong. The registry text below and the trial team decide who can take part.
The trial is looking for women aged 18-40 who have not reached menopause and have polycystic ovary syndrome (PCOS) with long, irregular periods.
- Age
- 18-40 years
- Sex
- Women only
- Disease stage
- PCOS according to the Rotterdam criteria, with irregular long menstrual cycles (more than 35 days). Premenopausal.
- Earlier treatment
- No hormonal medication (including contraception) in the 3 months before joining. A progestogen to bring on a period every 3 months is allowed. Women taking supplements are asked to stop them.
Main reasons for not taking part
- Hormonal medication in the last 3 months (except progestogen for withdrawal bleeding every 3 months)
- Conditions or medicines that affect vitamin D or raise calcium, such as tuberculosis, sarcoidosis, kidney stones, parathyroid disease, kidney or liver failure, or anti-convulsants
- Use of insulin-sensitizing, lipid-lowering or blood pressure drugs, now or expected within the next year
- Known type 2 diabetes
- Abnormal blood calcium level
The registry criteria, word for word
Show all 12 criteriaShow less
Who can take part
- Premenopausal
- Aged 18-40 years
- Irregular long menstrual cycles (>35 days)
- PCOS according to the Rotterdam criteria
- Agree for transvaginal ultrasound
Who cannot take part
- Use of hormonal medication (including contraception) within 3 months prior to study inclusion, except the use of a progestogen to induce withdrawal bleeding every 3 months
- Use of insulin-sensitizing drugs, lipid lowering drugs or anti-hypertensive
- Anticipated to use the above medications in the coming one year
- History of any medical condition or medications that may predispose to vitamin D sensitivity, altered vitamin D metabolism and/ or hypercalcemia, including active tuberculosis or current therapy for tuberculosis, sarcoidosis, history of renal/ ureteral stones, parathyroid disease, renal or liver failure or current use of anti-convulsants
- Known type 2 diabetes mellitus
- Abnormal blood calcium level; For those on supplements, we asked them to stop their own supplements
- Refusal to join the study
Check if you might fit
Answer for yourself. This is not a decision: only the study team can say whether you can take part.
- Are you between 18 and 40 years old?
Where in Hong Kong
- Kwong Wah HospitalHong Kong, Hong KongContact: Shui Fan Lai, MBBS, MRCOGTaking people
- Princess Margaret HospitalHong Kong, Hong KongContact: Rebecca S.F. Wan, MBBS, MRCOGNot yet recruiting
- Queen Mary Hospital University of Hong KongHong Kong, Hong KongContact: Jennifer Ka Yee Ko, MBBSTaking people
About the trial
What the trial wants to find out
This is a randomized double-blind controlled trial on the effect of vitamin D supplementation to assess the ovulation rate of women with polycystic ovary syndrome (PCOS) and other reproductive, endocrine and metabolic outcomes after one year of treatment.
The 2 groups in the trial
- Vitamin DExisting treatment, for comparison
Vitamin D 50,000 IU/ week for 4 weeks, followed by 50,000 IU once every 2 weeks for 52 weeks Those who remain anovulatory after 6 months will be treated with a 6-month course of letrozole (2.5mg to 7.5mg for 5 days per cycle titrated according to response) for ovulation induction.
- PlaceboPlacebo, for comparison
Placebo tablets with same external appearance for 52 weeks Those who remain anovulatory after 6 months will be treated with a 6-month course of letrozole (2.5mg to 7.5mg for 5 days per cycle titrated according to response) for ovulation induction.
Questions to ask the study team
- How often do I need to come in, and for how long each time?
- Are travel costs paid?
- Can I keep my own doctor?
- What happens if I want to stop?
Contact the study team: see the registry record → Contacts and Locations
Print a page for my doctorData and sources
- Registry record
- Listed on ClinicalTrials.gov.
- Official title
- A Randomized Double-blind Controlled Trial on the Effect of Vitamin D on Ovulation Rate of Women With Polycystic Ovary Syndrome
- Plain-language title
- Tests vitamin D against a placebo in women with polycystic ovary syndromeGenerated from the registry record. The registry title is the official one.
- AI summary
- From the trial's eligibility criteria. Read by machine on 12 November 2026.
- Fit questions
- Built from NCT04650880, who can take part
- Publications
- Record updated
- 14 May 2024