Reproductive IssuesPhase 2NCT05050916
The Investigation of Vitamin D and Menstrual Cycles Trial, the inVitD Trial: A Phase II Clinical Trial
A Phase 2 study testing Vitamin D in people with Reproductive Issues, run by National Institute of Environmental Health Sciences (NIEHS) at 2 sites in United States.
Trial 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. Read more about this study
- Who is it for?
- Ages 19 to 40 years, women only
- Conditions the study is for
- Reproductive Issues
- What is being tested?
- Vitamin D
- Type of treatment
- Pill or oral medicine
- Could I receive a placebo?
- Yes, some participants may receive a placebo
- How many people
- 998 participants
- Where
- 2 sitesUnited States
- Study dates
- 17 Mar 2023to 27 Jun 2024
- Phase
- Phase 2
- Are there results?
- None posted in the registry
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 19 to 40 years
- Women only
- No healthy volunteers
- Adult
Who may be able to join
- In order to be eligible to participate in this study, an individual must meet all of the following criteria:
- Provision of signed and dated informed consent form
- Stated willingness to comply with all study procedures and availability for the duration of the study
- Having natural, spontaneous menstrual cycles (no hormonal therapy) less than 50 days in length.
- Aged 19-40 years
- Ability to take a vitamin D capsule and willing to adhere to the weekly regimen
- If sexually active, use of a non-hormonal contraceptive method.
Who cannot join
- An individual who meets any of the following criteria will be excluded from participation in this study:
- No menstrual period in the last 50 days, or, a typical menstrual cycle length <16 or >49 days.
- Use of a vitamin D supplement for more than one month and on more than 15 days out of each month. Volunteers will be asked to check their supplement label for vitamin D content.
- Unwilling to abstain from taking non-study vitamin D supplements during the study or if already taking a medically-advised vitamin D supplement.
- Use of a calcium supplement (including certain antacids) and unwilling to abstain from taking a calcium supplement during the study.
- Known polycystic ovarian syndrome
Show all 26Show fewer
- Depo-provera use in the previous 12 months
- Current use of any hormones, including birth control
- Current use of a hormonal intrauterine device (IUD)
- Current pregnancy or lactation, trying to become pregnant, or planning to try in the next four menstrual cycles or 5 months.
- History of seizure disorders
- Celiac disease
- Crohn s Disease
- Body mass index >35
- Aged <19 or > 40 years
- Presence of known contraindications for vitamin D supplementation, history of any of the following: calcium disorder or hypercalcemia, tuberculosis or granulomatous disease, metastatic bone disease, sarcoidosis, Williams syndrome, kidney disease (kidney stones, renal failure or dialysis, lupus nephritis)
- Known liver disease (cirrhosis)
- History of cancer other than skin cancer.
- History of anorexia nervosa, bulimia or an eating disorder
- Use within the past 60 days, of exogenous hormones
- Type 1 or Type 2 diabetes
- Known heart disease
- Gastric bypass surgery
- Unwilling or unable to complete study activities, e.g. collect daily urine specimens, have blood drawn, complete daily diaries, attend in person study visits
- 25. Non-English speaking
- Due to the complexity of daily/weekly diaries, testing and procedurerequirements, all consents, instructions and questionnaires are provided in English. Therefore, all participants must be able to able to read and speak English.
Trial locations and contacts
2 sites in 1 country.
United States2 sites
Henry Ford Health System
Detroit, Michigan, 48187
NIEHS Clinical Research Unit (CRU)
Research Triangle Park, North Carolina, 27709
About this study
Official title: The Investigation of Vitamin D and Menstrual Cycles 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 role vitamin D may play in menstrual cycle health.
Read more
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)....
Read the detailed description
Study Description:
This Phase II clinical trial translates both animal studies and human observational research into public health relevant research. We will investigate vitamin D's influence on the hypothalamic-pituitary-ovarian axis by careful evaluation of hormonal and ovulatory menstrual cycle changes that occur with vitamin D supplementation. Vitamin D supplementation may be a low-cost intervention that improves menstrual cycle function and fertility.
After recruitment, there will be two phases to this study: Phase 1 will follow all women for at least one menstrual cycle prior to supplementation, the pre-supplementation cycle. During Phase 1, blood will be drawn and assayed for 25-hydroxyvitamin D (25OHD). If their level is less than 20 ng/ml, they will be invited to participate in Phase 2. A small sample of participants with a level >= 20 ng/ml will also be invited to participate in Phase 2, to maintain participant blinding. Participation ends for the remaining participants whose level is 20 ng/ml or higher. During Phase 2, those with low vitamin D receive a blinded dose of 50,000 IU/week of vitamin D supplementation. The small group of sufficient participants will receive a placebo. Participants will not be told what their 25OHD level was. Women will be followed for three more menstrual cycles. In the pre-supplementation cycle and in the last supplemented cycle, women will collect daily urine specimens. Hormone levels will be compared between the pre-supplementation and supplemented cycles as the primary analysis. A secondary analysis will compare the supplemented cycles in those who received 50,000 IU and those who received placebo.
The original design of this trial included a low-dose (4,200 IU) vitamin D supplementation arm. At entry into Phase 2, participants were randomized to receive the 4,200 IU/week vitamin D supplement or 50,000 IU/week vitamin D supplement in a 2:3 ratio. The low-dose arm of the trial has been discontinued for cost and efficiency purposes. As of 12/13/22, 16 participants were randomized to receive the low-dose vitamin D supplement. On approval of the current document, this information will be updated to reflect the final count of participants who received the low-dose vitamin D supplement and the specific date at which the low-dose arm was discontinued via a future amendment. Study data for those who received the low-dose vitamin D supplement will be retained for research and analysis. Specific analyses, biospecimen use, and statistical comparisons will not differ from those described below for the participants who receive the 50,000 IU vitamin D supplement or the placebo. All data handling and security procedures described in this document equivalently apply to data collected from participants receiving the low-dose vitamin D supplement.
The primary aim of this trial will test the following hypotheses by comparing vitamin D supplemented cycles to the pre-supplementation cycles, within-woman: (1) Mid-luteal progesterone is higher in vitamin D supplemented cycles; (2) Rate of estrogen rise is higher in vitamin D supplemented cycles; (3) Pre-ovulatory luteinizing hormone (LH) is higher in vitamin D supplemented cycles.
Objectives:
Primary objective:
-To examine the effect of vitamin D supplementation on hypothalamic-pituitary-ovarian axis hormones. We will evaluate the extent to which vitamin D supplementation:
- Increases urinary mid-luteal progesterone (an indicator of healthy, fertile follicle development)
- Increases the rate of rise in urinary follicular phase estrogen (an indicator of follicular development)
- Increases urinary pre-ovulatory LH (an indicator of healthy ovarian-hypothalamic interaction)
Secondary objectives:
- Determine the impact of vitamin D supplementation in reproductive-aged women by assaying the metabolome before and after vitamin D supplementation
- To quantify the increase in 25OHD and the fraction who achieve a level of 40 ng/ml after 1.5 and 3 months of supplementation, in response to 50,000 IU/week of vitamin D.
- To examine the effects of vitamin D supplementation on endometrial stromal cell decidualization
Tertiary/Exploratory objectives:
- To examine the change in whole blood metals levels in response to vitamin D supplementation.
- To examine the change in vaginal or oral microbiome in response to vitamin D supplementation.
- To investigate the extent to which vitamin D reduces the incidence of --delayed ovulation (follicular phase >20 days), 2) short luteal phase (<=10 days), and 3) long cycles (>34 days)
- To investigate the association between 25OHD levels, sleep measures, physical activity, exposure to white/red/green/blue light, and hypothalamic-pituitary-ovarian axis hormones.
Endpoints:
Primary Endpoint: Mid-luteal progesterone, follicular estrogen, preovulatory LH
Secondary Endpoints: Untargeted metabolomics, 25OHD, endometrial stromal cell function,
Tertiary Endpoints: metals, microbiome, ovulation, menstrual cycle length, sleep
- Conditions
- Reproductive Issues
- Being tested
- Vitamin D, Placebo
- Keywords
- reproductive, Health, Female, Hormones, period
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Vitamin DDietary supplement
The High Dose Vitamin D arm will receive 50,000 IU/week of cholecalciferol. The Low Dose Vitamin D arm will receive 4,200 IU/week of cholecalciferol
PlaceboOther
Cellulose capsule
| Study group | Role | What they receive |
|---|---|---|
| 1/High Dose Vitamin D | Experimental | Deficient participants will be assigned to the Endocrine Society recommendation for deficiency, 50,000 IU/week. Receives: Dietary Supplement: Vitamin D |
| 2/Placebo | Placebo comparator | Participants with sufficient levels of vitamin D will receive placebo instead of Vitamin D supplementation. Receives: Other: Placebo |
| 3/Low Dose Vitamin D | Experimental | Early in the study, deficient participants were randomized to either the U.S. recommended daily allowance, 4200 IU/week or the high dose vitamin D arm. The low dose arm was discontinued mid-way through the trial and all deficient participants were assigned to the high dose arm. Receives: Dietary Supplement: Vitamin D |
What is being measured
The primary outcome is the main question the study is designed to answer.
To examine the effect of vitamin D supplementation on hypothalamic-pituitary-ovarian axis hormones.
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)
Measured: 60 months
Secondary outcomes (5)
To quantify the increase in 25OHD and the fraction who achieve a level of 40 ng/ml after 1.5 and 3 months of supplementation, in response to 50,000 IU/week of vitamin D.
25OHD
Measured: 60 months
To investigate the effect of vitamin D supplementation on the microbiome
Untargeted microbiome profiling
Measured: 60 months
To investigate the effect of vitamin D supplementation on endometrial stromal cell function.
Endometrial stromal cells isolated from menstrual effluent.
Measured: 60 months
To examine the change in whole blood metals levels in response to vitamin D supplementation.
Whole blood lead
Measured: 60 months
Determine the impact of Vitamin D supplementation in reproductive-aged women by assaying the metabolome before and after vitamin D supplementation.
Untargeted metabolomics
Measured: 60 months
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted21 Sep 2021
- Study start17 Mar 2023
- Primary completion7 Jun 2024
- Study completion27 Jun 2024
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (1)Papers the sponsor has linked to this study.
- Other trials for Reproductive IssuesStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase 2
- Primary purpose
- Basic science
- Allocation
- Non-randomised
- Intervention model
- Parallel groups
- Masking
- Triple blind
- Who is masked
- Participant, Investigator, Outcomes assessor
- Enrolment
- 998 participants (actual)
Sponsor and investigators
- Lead sponsor
- National Institute of Environmental Health Sciences (NIEHS)
- Sponsor type
- US National Institutes of Health
- Responsible party
- Sponsor
- Investigators
- Anne Marie Z Jukic, Ph.D., Principal investigator, National Institute of Environmental Health Sciences (NIEHS)
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT05050916
- Sponsor's protocol ID
- 10000476
- Other IDs
- 000476-E
- Status last verified
- 9 Sep 2026
- First submitted
- 18 Sep 2021
- Last updated
- 5 Nov 2026
- Results posted
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- Undecided
Publications
Metz CN, Chatterjee PK, Hyman N, Busch S, Tarasenko SA, Hoofnagle AN, Gregersen PK, Steiner AZ, Jukic AMZ. Leveraging Menstrual Effluent to Investigate Vitamin D and Human Decidualization: A Potential Link with Fertility. J Clin Endocrinol Metab. 2026 May 19;111(6):e1532-e1543. doi: 10.1210/clinem/dgaf708.
PubMed 41492807
Study at a glance
From the registry record, last updated by the sponsor on 5 Nov 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- The Investigation of Vitamin D and Menstrual Cycles Trial: A Phase II Clinical Trial
- ClinicalTrials.gov ID
- NCT05050916
- Acronym / sponsor ID
- 10000476
- Conditions
- Reproductive Issues
- Keywords
- reproductive, Health, Female, Hormones, period
- Phase
- Phase 2
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 998 participants (actual)
- Lead sponsor
- National Institute of Environmental Health Sciences (NIEHS)US National Institutes of Health
- Study start
- 17 Mar 2023 (actual)
- Primary completion
- 7 Jun 2024 (actual)
- Study completion
- 27 Jun 2024 (actual)
- First posted
- 21 Sep 2021 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
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)....
Detailed description
Study Description:
This Phase II clinical trial translates both animal studies and human observational research into public health relevant research. We will investigate vitamin D's influence on the hypothalamic-pituitary-ovarian axis by careful evaluation of hormonal and ovulatory menstrual cycle changes that occur with vitamin D supplementation. Vitamin D supplementation may be a low-cost intervention that improves menstrual cycle function and fertility.
After recruitment, there will be two phases to this study: Phase 1 will follow all women for at least one menstrual cycle prior to supplementation, the pre-supplementation cycle. During Phase 1, blood will be drawn and assayed for 25-hydroxyvitamin D (25OHD). If their level is less than 20 ng/ml, they will be invited to participate in Phase 2. A small sample of participants with a level >= 20 ng/ml will also be invited to participate in Phase 2, to maintain participant blinding. Participation ends for the remaining participants whose level is 20 ng/ml or higher. During Phase 2, those with low vitamin D receive a blinded dose of 50,000 IU/week of vitamin D supplementation. The small group of sufficient participants will receive a placebo. Participants will not be told what their 25OHD level was. Women will be followed for three more menstrual cycles. In the pre-supplementation cycle and in the last supplemented cycle, women will collect daily urine specimens. Hormone levels will be compared between the pre-supplementation and supplemented cycles as the primary analysis. A secondary analysis will compare the supplemented cycles in those who received 50,000 IU and those who received placebo.
The original design of this trial included a low-dose (4,200 IU) vitamin D supplementation arm. At entry into Phase 2, participants were randomized to receive the 4,200 IU/week vitamin D supplement or 50,000 IU/week vitamin D supplement in a 2:3 ratio. The low-dose arm of the trial has been discontinued for cost and efficiency purposes. As of 12/13/22, 16 participants were randomized to receive the low-dose vitamin D supplement. On approval of the current document, this information will be updated to reflect the final count of participants who received the low-dose vitamin D supplement and the specific date at which the low-dose arm was discontinued via a future amendment. Study data for those who received the low-dose vitamin D supplement will be retained for research and analysis. Specific analyses, biospecimen use, and statistical comparisons will not differ from those described below for the participants who receive the 50,000 IU vitamin D supplement or the placebo. All data handling and security procedures described in this document equivalently apply to data collected from participants receiving the low-dose vitamin D supplement.
The primary aim of this trial will test the following hypotheses by comparing vitamin D supplemented cycles to the pre-supplementation cycles, within-woman: (1) Mid-luteal progesterone is higher in vitamin D supplemented cycles; (2) Rate of estrogen rise is higher in vitamin D supplemented cycles; (3) Pre-ovulatory luteinizing hormone (LH) is higher in vitamin D supplemented cycles.
Objectives:
Primary objective:
-To examine the effect of vitamin D supplementation on hypothalamic-pituitary-ovarian axis hormones. We will evaluate the extent to which vitamin D supplementation:
- Increases urinary mid-luteal progesterone (an indicator of healthy, fertile follicle development)
- Increases the rate of rise in urinary follicular phase estrogen (an indicator of follicular development)
- Increases urinary pre-ovulatory LH (an indicator of healthy ovarian-hypothalamic interaction)
Secondary objectives:
- Determine the impact of vitamin D supplementation in reproductive-aged women by assaying the metabolome before and after vitamin D supplementation
- To quantify the increase in 25OHD and the fraction who achieve a level of 40 ng/ml after 1.5 and 3 months of supplementation, in response to 50,000 IU/week of vitamin D.
- To examine the effects of vitamin D supplementation on endometrial stromal cell decidualization
Tertiary/Exploratory objectives:
- To examine the change in whole blood metals levels in response to vitamin D supplementation.
- To examine the change in vaginal or oral microbiome in response to vitamin D supplementation.
- To investigate the extent to which vitamin D reduces the incidence of --delayed ovulation (follicular phase >20 days), 2) short luteal phase (<=10 days), and 3) long cycles (>34 days)
- To investigate the association between 25OHD levels, sleep measures, physical activity, exposure to white/red/green/blue light, and hypothalamic-pituitary-ovarian axis hormones.
Endpoints:
Primary Endpoint: Mid-luteal progesterone, follicular estrogen, preovulatory LH
Secondary Endpoints: Untargeted metabolomics, 25OHD, endometrial stromal cell function,
Tertiary Endpoints: metals, microbiome, ovulation, menstrual cycle length, sleep
Study design
- Primary purpose
- Basic science
- Allocation
- Non-randomised
- Intervention model
- Parallel groups
- Masking
- Triple blind (participant, investigator, outcomes assessor)
- Number of arms
- 3
| Arm | Type | Receives |
|---|---|---|
| 1/High Dose Vitamin D | Experimental | Dietary Supplement: Vitamin DDeficient participants will be assigned to the Endocrine Society recommendation for deficiency, 50,000 IU/week. |
| 2/Placebo | Placebo comparator | Other: PlaceboParticipants with sufficient levels of vitamin D will receive placebo instead of Vitamin D supplementation. |
| 3/Low Dose Vitamin D | Experimental | Dietary Supplement: Vitamin DEarly in the study, deficient participants were randomized to either the U.S. recommended daily allowance, 4200 IU/week or the high dose vitamin D arm. The low dose arm was discontinued mid-way through the trial and all deficient participants were assigned to the high dose arm. |
Who may qualify
- Ages
- 19 to 40 years
- Sex
- Female only
- Healthy volunteers
- Not accepted
- Age groups
- Adult
Key inclusion criteria (7 listed)
- In order to be eligible to participate in this study, an individual must meet all of the following criteria:
- Provision of signed and dated informed consent form
- Stated willingness to comply with all study procedures and availability for the duration of the study
- Having natural, spontaneous menstrual cycles (no hormonal therapy) less than 50 days in length.
- Aged 19-40 years
Key exclusion criteria (26 listed)
- An individual who meets any of the following criteria will be excluded from participation in this study:
- No menstrual period in the last 50 days, or, a typical menstrual cycle length <16 or >49 days.
- Use of a vitamin D supplement for more than one month and on more than 15 days out of each month. Volunteers will be asked to check their supplement label for vitamin D content.
- Unwilling to abstain from taking non-study vitamin D supplements during the study or if already taking a medically-advised vitamin D supplement.
- Use of a calcium supplement (including certain antacids) and unwilling to abstain from taking a calcium supplement during the study.
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Vitamin DThe High Dose Vitamin D arm will receive 50,000 IU/week of cholecalciferol. The Low Dose Vitamin D arm will receive 4,200 IU/week of cholecalciferol | Dietary supplement | 1/High Dose Vitamin D, 3/Low Dose Vitamin D |
| PlaceboCellulose capsule | Other | 2/Placebo |
Primary outcome
To examine the effect of vitamin D supplementation on hypothalamic-pituitary-ovarian axis hormones.
Time frame: 60 months
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)
5 secondary outcomes
To quantify the increase in 25OHD and the fraction who achieve a level of 40 ng/ml after 1.5 and 3 months of supplementation, in response to 50,000 IU/week of vitamin D.
Time frame: 60 months
To investigate the effect of vitamin D supplementation on the microbiome
Time frame: 60 months
To investigate the effect of vitamin D supplementation on endometrial stromal cell function.
Time frame: 60 months
To examine the change in whole blood metals levels in response to vitamin D supplementation.
Time frame: 60 months
Determine the impact of Vitamin D supplementation in reproductive-aged women by assaying the metabolome before and after vitamin D supplementation.
Time frame: 60 months
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 5 Nov 2026.
- Derived from this study: PubMed 41492807Metz CN, Chatterjee PK, Hyman N, Busch S, Tarasenko SA, Hoofnagle AN, Gregersen PK, Steiner AZ, Jukic AMZ. Leveraging Menstrual Effluent to Investigate Vitamin D and Human Decidualization: A Potential Link with Fertility. J Clin Endocrinol Metab. 2026 May 19;111(6):e1532-e1543. doi: 10.1210/clinem/dgaf708.
- NIH Clinical Center Detailed Web PageLink provided by the sponsor.
- Individual participant dataSharing planned: Undecided
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
Anne Marie Z Jukic, Ph.D. principal investigator
National Institute of Environmental Health Sciences (NIEHS)
2 sites in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Phase 2 study testing Vitamin D in people with Reproductive Issues, run by National Institute of Environmental Health Sciences (NIEHS) at 2 sites in United States.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 7 inclusion and 26 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 5 Nov 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 2 sites in United States. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. Some participants in this study may receive a placebo. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
What does this phase mean?
Phase 2 studies give the treatment to a larger group to see whether it has the intended effect and to keep checking safety.
Not every study follows the same path, and some studies (observational studies, device studies) have no phase.
Are results available for this study?
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
To examine the effect of vitamin D supplementation on hypothalamic-pituitary-ovarian axis hormones. (time frame: 60 months). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
On the ClinicalTrials.gov record for NCT05050916, which also lists 1 linked publication.
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 5 Nov 2026.