Effect of Vitamin D on Endometrial Receptivity in Women with Infertility

Effect of Vitamin D on Vaginal / Endometrial Biomarkers and Endometrial Receptivity in Women With Fertility Problems

This study is testing if taking vitamin D can improve the chances of pregnancy by helping the lining of the uterus in women under 40 who are having trouble getting pregnant.

Quick facts

• Study type: Observational
• Enrollment: 105 (estimated)
• Ages: 18 Years to 40 Years
• Sex: Female
• Sponsor: The University of Hong Kong (other)
• Locations: 1 site (Hong Kong)
• Trial ID: NCT04721899 on ClinicalTrials.gov

What this trial studies

This observational study aims to evaluate the impact of vitamin D supplementation on endometrial receptivity in women experiencing fertility issues. Participants will undergo vaginal swabs and endometrial biopsies before and after an 8-week regimen of vitamin D, with the goal of assessing changes in biomarkers and trophoblast attachment rates. The study will include women under 40 with normal uterine cavities and regular ovulatory cycles, divided into groups based on their infertility history. The laboratory staff will remain blinded to the vitamin D treatment during the analysis.

Who should consider this trial

Good fit: Ideal candidates for this study are women under 40 with normal uterine anatomy and regular ovulatory cycles who are experiencing infertility.

Not a fit: Patients with medical conditions affecting vitamin D metabolism or those with a history of certain health issues may not benefit from this study.

Why it matters

Potential benefit: If successful, this study could enhance understanding of how vitamin D affects fertility, potentially improving outcomes for women with infertility.

How similar studies have performed: While the role of vitamin D in fertility is being explored, this specific approach of assessing its impact on endometrial receptivity is relatively novel.

Eligibility criteria

Inclusion Criteria:

* Age of women \< 40years old
* Normal uterine cavity as demonstrated by pelvic scanning with or without saline infusion sonogram or hysteroscopy
* Regular ovulatory cycles

They will be divided into three groups:

* RIF patients (n=35)- those who have failed to get pregnant after replacing four or more cleavage stage embryos or two or more blastocysts in two consecutive transfers.
* RPL patients (n=35)- those who have failed in three pregnancies before 24 weeks of gestation and includes embryonic and fetal losses.
* 'Infertile group'(n=35)- infertility except RIF and RPL, e.g. those seeking for preimplantation genetic testing, male factor infertility, unexplained infertility.

Exclusion Criteria:

* 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
* Taking vitamin D supplement
* Endometrial polyp or fibroid distorting the uterine cavity
* Presence of hydrosalpinx not corrected surgically
* Refusal to join the study

  • Discontinuation criteria-
* If the woman becomes pregnant during the study
* Pelvic inflammatory disease/ uterine perforation after endometrial biopsy
* Vitamin D toxicity (hypercalcemia)
* Withdrawal by patient

Where this trial is running

Hong Kong

• Queen Mary Hospital — Hong Kong, Hong Kong (RECRUITING)

Study contacts

• Study coordinator: Jennifer KY Ko

Conditions: Infertility, vitamin D, endometrial receptivity, infertility, recurrent pregnancy loss, recurrent implantation failure