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NCT05050916 · ClinicalTrials.gov registry record · Phase 2
The Investigation of Vitamin D and Menstrual Cycles Trial, the inVitD Trial: A Phase II Clinical Trial
A Phase 2 study of Reproductive Issues, sponsored by National Institute of Environmental Health Sciences (NIEHS).
- Completed
- Registry status
- Phase 2
- Development phase
- 57
- Enrollment target
- 2
- Study locations
NCT05050916: Completed Phase 2 study of Reproductive Issues, sponsored by National Institute of Environmental Health Sciences (NIEHS).
NCT05050916 is a Phase 2 study of Reproductive Issues that has completed, run by National Institute of Environmental Health Sciences (NIEHS). The registered enrollment target is 57 participants, below the 133-participant average among 30,622 other Phase 2 trials with a reported enrollment target (57% lower). The trial reports 2 study locations across 2 states. According to ClinicalTrials.gov, the official US trial registry.
The verdict
NCT05050916, a Phase 2 study of Reproductive Issues, has completed, sponsored by National Institute of Environmental Health Sciences (NIEHS).
- COMPLETED
- Registry status
- Phase 2
- Development phase
- 57 participants
- Enrollment target
- 2
- Study locations
Study Summary
Background: About 1.5 million U.S. women of reproductive age are estimated to be infertile. Many more have difficulty getting pregnant. Menstrual cycles are an indicator of a woman's general health. Menstrual cycle changes may predict difficulties in getting pregnant. Researchers want to see what role vitamin D may play in menstrual cycle health. Objective: To examine the effect of vitamin D supplementation on the hormones that come from the brain and the ovary during a menstrual cycle. Eligibility: Women aged 19-40 who have spontaneous menstrual cycles (are not taking any hormones) less than 50 days in length. Design: Participants will fill out a screening survey about their demographics and health history. It will take 5-10 minutes to complete. Participants will have 3 study visits. Participants who have low vitamin D and move to Phase 2 will receive 50000 IU//week of vitamin D supplement. Participants who do not have low vitamin D will receive placebo. If they have low vitamin D, they will not get the placebo. They will take the capsules by mouth, once per week, for 3 menstrual cycles (or about 90 days). Participants will have physical exams. Their height, weight, body fat percentage, blood pressure, and waist-hip ratio will be measured. They will give blood samples. They will self-administer vaginal and oral swabs. Participants will keep a daily menstrual diary. They will do daily home ovulation testing. They will collect urine at home. Some women may collect menstrual blood at home. Participants will fill out an online survey. It will ask about their health, diet, and physical activity; birth control use; pregnancy history; menstrual cycle; smoking and drinking habits; education; and occupation. It will take 20-30 minutes to complete. Participation will last for four menstrual cycles (about 4 months).
Primary Outcome
We will evaluate the extent to which vitamin D supplementation: 1) Increases urinary mid-luteal progesterone (an indicator of healthy, fertile follicle development) 2) Increases the rate of rise in urinary follicular phase estrogen (an indicator of follicular development) 3) Increases urinary pre-ovulatory LH (an indicator of healthy ovarian-hypothalamic interaction)
Conditions Studied
Interventions
- OTHER Placebo
- DIETARY_SUPPLEMENT Vitamin D
Study Locations (2)
Michigan
- Henry Ford Health System - Detroit
North Carolina
- NIEHS Clinical Research Unit (CRU) - Research Triangle Park
Trial Details
| Field | Value |
|---|---|
| Enrollment Target | 57 participants |
| Start Date | 2023-03-17 |
| Est. Completion | 2024-06-27 |
| Phase | Phase 2 |
What the finished NCT05050916 record still lists
NCT05050916 is an interventional study that assigns participants to a tested intervention. The registry caps enrollment at 57 participants, a relatively small participant target, below the 133-participant average among 30,622 other Phase 2 trials with a reported enrollment target (57% lower).
The record links to 1 condition, with Reproductive Issues appearing as the primary indexed condition, and to 2 interventions - of which Placebo is the first listed.
NCT05050916 reports a single indexed study location in Michigan, North Carolina.
Frequently Asked Questions
What is clinical trial NCT05050916 about?
NCT05050916 is a clinical study titled "The Investigation of Vitamin D and Menstrual Cycles Trial, the inVitD Trial: A Phase II Clinical Trial". Background: About 1.5 million U.S. women of reproductive age are estimated to be infertile. Many more have difficulty getting pregnant. Menstrual cycles are an indicator of a woman's general health. Menstrual cycle changes may predict difficulties in getting pregnant. Researchers want to see what r...
What is the current status of trial NCT05050916?
This trial is currently completed. It is a Phase 2 study. The enrollment target is 57 participants. The study started on 2023-03-17. Estimated completion is 2024-06-27.
What conditions does trial NCT05050916 study?
This clinical trial studies the following conditions: Reproductive Issues.
What interventions are being tested in trial NCT05050916?
The interventions under investigation include: Placebo (OTHER), Vitamin D (DIETARY_SUPPLEMENT).
Who is sponsoring clinical trial NCT05050916?
This trial is sponsored by National Institute of Environmental Health Sciences (NIEHS), which has 145 total clinical trials registered on ClinicalTrials.gov.
Where is trial NCT05050916 being conducted?
This trial has 2 study locations across Michigan, North Carolina. Contact the study sites directly through ClinicalTrials.gov for enrollment availability.
Learn More About Clinical Trials
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Where NCT05050916's enrollment target sits among peer trials
57 1141st of 2000 higher than 855 of 2,000 other Phase 2 trials
participants (enrollment target), bucketed by value
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Source ClinicalTrials.gov registry export · 2026-08-08
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