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

Not Applicable

Recruiting

Brief Summary: 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.

Detailed 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.

Recruitment & Eligibility

Inclusion Criteria

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.

Arm && Interventions

Group	Intervention	Description
Vitamin D	Vitamin D	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.
Placebo	Placebo	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.

Primary Outcome Measures

Name	Time	Method
Ovulation rate	12 months	Serum progesterone

Secondary Outcome Measures

Name	Time	Method
Pregnancy rate	12 months	Positive urine or serum hCG test
Change in antral follicle count	12 months	Antral follicle count measured by transvaginal/ transrectal ultrasound
Live birth rate	12 months	Delivery of a baby after 22 completed weeks of gestational age, or with birth weight of 500 grams if the gestation age is unknown, which shows evidence of life
Androgen indices	12 months	serum androgen and androstenedione levels, SHBG
Body mass index	12 months	Height in cm, weight in kg, to calculate the body mass index (kg/m\^2)
Change in systolic and diastolic blood pressure	12 months	Blood pressure
Change in serum 25(OH)D level	12 months	Serum 25(OH)D
Change in waist and hip circumference	12 months	waist and hip circumference in cm
Change in serum anti-Mullerian hormone level	12 months	serum AMH level
Rate of diabetes mellitus/ impaired glucose intolerance	12 months	Measured by fasting and 2 hour glucose (post 75g OGTT)

Locations (3): Queen Mary Hospital, University of Hong Kong
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Hong Kong, Hong Kong
Kwong Wah Hospital
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Hong Kong, Hong Kong
Princess Margaret Hospital
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Hong Kong, Hong Kong