Clinical trial · Interventional
Effect of Vitamin D on Ovulation Rate in Women With Polycystic Ovary Syndrome
A Randomized Double-blind Controlled Trial on the Effect of Vitamin D on Ovulation Rate of Women With Polycystic Ovary Syndrome
NCT04650880CI-TRIAL-00077151recruitingN/AClinicalTrials.gov clinicaltrialsProvenance
- Source
- ClinicalTrials.gov
- Retrieved
- Sep 8, 2026
- Layer
- normalized (units and labels harmonized; values unchanged)
- Run
- ING-CLINICALTRIALS-20260908-000001
Summary
Brief summary (as posted)
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.
Conditions
Conditions (2)
Free-text conditions as registered, with the CancerIndex entity they were reconciled to and the match type.
| Condition (as posted) | Mapped entity | Match | Confidence |
|---|---|---|---|
| Anovulation | — | UNRESOLVED | — |
| Polycystic Ovary Syndrome | — | UNRESOLVED | — |
Interventions
Interventions (2)
| Intervention | Type | Mapped drug | Match |
|---|---|---|---|
| Placebo | Other | — | UNRESOLVED |
| Vitamin D | Dietary Supplement | — | UNRESOLVED |
Design
Arms and outcomes
Arms (2)
- type
- ACTIVE_COMPARATOR
- label
- Vitamin D
- description
- 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.
- interventionNames
- Dietary Supplement: Vitamin D
- type
- PLACEBO_COMPARATOR
- label
- Placebo
- description
- 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.
- interventionNames
- Other: Placebo
Primary outcomes (1)
Eligibility
Eligibility (as posted)
- Sex
- Female
- Minimum age
- 18 Years
- Maximum age
- 40 Years
Show eligibility criteria text
Inclusion Criteria: * Premenopausal * Aged 18-40 years * Irregular long menstrual cycles (\>35 days) * PCOS according to the Rotterdam criteria * Agree for transvaginal ultrasound Exclusion Criteria: * 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 * 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 * Use of insulin-sensitizing drugs, lipid lowering drugs or anti-hypertensive * Anticipated to use the above medications in the coming one year * Known type 2 diabetes mellitus * Refusal to join the study * Abnormal blood calcium level For those on supplements, we asked them to stop their own supplements.
References
Publications (1)
- DERIVEDKo JKY, Yung SSF, Lai SF, Wan RSF, Wong CKY, Wong K, Cheung CL, Ng EHY, Li RHW. Effect of vitamin D in addition to letrozole on the ovulation rate of women with polycystic ovary syndrome: protocol of a multicentre randomised double-blind controlled trial. BMJ Open. 2024 Apr 29;14(4):e070801. doi: 10.1136/bmjopen-2022-070801. PMID 38684265