Work

Investigating the Association Between Serum 25‐Hydroxyvitamin D (25(OH)D) and Body Mass Index (BMI) With In Vitro Fertilization (IVF) Outcomes Among Iranian Women: A Case‐Control Study

Year: 2026

Type: article

Abstract: ABSTRACT Background and Aims Infertility affects approximately 18.3% of couples in Iran, and in vitro fertilization (IVF) remains a widely used treatment. Vitamin D deficiency and elevated body mass index (BMI) have been linked to poorer reproductive outcomes in some populations, but region‐specific evidence among Iranian women is limited. This study aimed to investigate the association between serum 25‐hydroxyvitamin D [25(OH)D] levels, BMI, and IVF outcomes in Iranian women. Methods This case‐control study was conducted at Fatemieh Medical Training Center, Hamadan, Iran. A total of 314 women undergoing IVF were included (157 with successful clinical pregnancy confirmed by positive β‐hCG test and 157 with unsuccessful outcomes). Serum 25(OH)D levels were measured using enzyme‐linked immunosorbent assay (ELISA). BMI was calculated as weight (kg)/height (m²) and categorized as normal (18.5–24.9), overweight (25–29.9), and obese (≥ 30). Exclusion criteria included systemic diseases, insulin resistance, polycystic ovary syndrome (PCOS), and diabetes. Data were collected using a researcher‐developed checklist from patient records. Statistical analyses were performed using Stata version 14. Pearson correlation coefficients were used to assess associations between continuous variables, and multivariable logistic regression was applied to estimate odds ratios (ORs) with 95% confidence intervals (CIs) for IVF failure, adjusting for age. All tests were two‐sided with a significance level of p < 0.05. Results Mean serum 25(OH)D levels were significantly lower in the unsuccessful IVF group (17.8 ± 5.9 ng/mL) compared to the successful group (24.6 ± 6.8 ng/mL; mean difference = 6.8 ng/mL, p < 0.001). BMI showed a moderate negative correlation with 25(OH)D levels ( r = −0.38, p < 0.01). Obese women (BMI ≥ 30) had a higher likelihood of IVF failure (adjusted OR = 2.3, 95% CI: 1.4–3.7, p = 0.001). Participant age (mean 33.2 ± 5.1 years, range 20–45) showed a weak positive correlation with unsuccessful outcomes ( r = 0.15, p = 0.04). Conclusion Vitamin D deficiency and higher BMI are independently associated with increased risk of IVF failure among Iranian women. Optimizing vitamin D status and achieving a healthy BMI prior to IVF treatment may improve success rates. Given the observed association, routine assessment and supplementation of vitamin D in women of reproductive age preparing for assisted reproductive technologies should be considered. Future studies should adjust for additional potential confounders, including chronic inflammation and lifestyle factors.

Source: Health Science Reports

DOI: 10.1002/hsr2.72029

Authors: Atefeh Asgari, Reza Mohammadi, Mohaddeseh Kalhori, Salman Khazaei, Azita Tiznobaik

Institution: Hamedan University of Medical Sciences

Language: English

Topic: Reproductive Health and Technologies

Subfield: Reproductive Medicine

Field: Medicine

Domain: Health Sciences

SDG: Good health and well-being

Open Access status: gold

Estimated APC paid: $3,280