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Effect of Vitamin D on Ovulation Rate in Women With Polycystic Ovary Syndrome

The University of Hong Kong (HKU) logo

The University of Hong Kong (HKU)

Status

Enrolling

Conditions

Polycystic Ovary Syndrome
Anovulation

Treatments

Dietary Supplement: Vitamin D
Other: Placebo

Study type

Interventional

Funder types

Other

Identifiers

NCT04650880
UW20-004

Details and patient eligibility

About

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.

Full description

The hypothesis is that vitamin D supplementation results in significant improvement in the ovulation rate of women with PCOS either spontaneously or with oral ovulation induction agent.

Anovulatory women with PCOS diagnosed by the Rotterdam criteria will be recruited.

Participants will be randomized to the (1) vitamin D group or (2) placebo group. Those in the vitamin D group will take vitamin D 50,000 IU/ week for 4 weeks, followed by 50,000IU once every 2 weeks for 52 weeks, whereas those in the placebo group will take placebo tablets with the same external appearance. 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.

The primary outcome is the ovulation rate and will be compared between the 2 groups.

Enrollment

220 estimated patients

Sex

Female

Ages

18 to 40 years old

Volunteers

No Healthy Volunteers

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.

Trial design

Primary purpose

Treatment

Allocation

Randomized

Interventional model

Parallel Assignment

Masking

Triple Blind

220 participants in 2 patient groups, including a placebo group

Vitamin D
Active Comparator group
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.
Treatment:
Dietary Supplement: Vitamin D
Placebo
Placebo Comparator group
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.
Treatment:
Other: Placebo

Trial contacts and locations

3

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Data sourced from clinicaltrials.gov

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