Micronutrient Deficiencies and Conception in Idiopathic Infertility: A Prospective Single-Centre Cohort Study

Abstract STRUCTURED ABSTRACT Objective To determine the prevalence of micronutrient deficiencies in women with confirmed idiopathic infertility, document laboratory improvement following individualised supplementation, and assess the association between deficiency correction and clinical pregnancy rates over 6 to 12 months. Design Prospective, single-centre, interventional cohort study. Setting: primary care fertility clinic, Dubai, United Arab Emirates, September 2023 to December 2024. STROBE-compliant. Subjects Twenty-seven women aged 18 to 40 years with confirmed idiopathic infertility after full standard workup per WHO 2021 criteria. Excluded: polycystic ovary syndrome, endometriosis, thyroid dysfunction, uterine anomaly, male-factor infertility, recent supplementation. No dropouts. Exposure Individualised supplementation targeting identified deficiencies: oral or intravenous iron; cholecalciferol; methylfolate; hydroxocobalamin and cyanocobalamin; calcium carbonate; magnesium glycinate; zinc picolinate. Structured dietary counselling provided to all. Main Outcome Measures Primary: confirmed clinical pregnancy (serum beta-hCG 25 mIU/mL or greater on two measurements 48 hours apart, with transvaginal ultrasound confirmation). Secondary: laboratory normalisation, time to conception, subgroup conception rates by age, infertility duration, prior IVF attempts, and chronic disease status. Results All 27 participants had at least one deficiency. Iron deficiency was most prevalent (70.4%), followed by vitamin D (55.6%), folate (51.9%), calcium (48.1%), vitamin B12 (25.9%), magnesium (25.9%), and zinc (22.2%). All values improved significantly after supplementation (all p less than 0.001); ferritin rose from 12.3 to 56.2 ng/mL and 25-hydroxyvitamin D from 18.4 to 35.8 ng/mL. Twenty of 27 women (74.1%) achieved confirmed pregnancy within 12 months. On exploratory logistic regression, infertility duration (OR 1.35, 95% CI 1.05 to 1.78) and absence of chronic disease (OR 2.10, 95% CI 1.02 to 4.34) were independent predictors (AUC 0.78). Ten of 20 conceptions occurred without concurrent assisted reproductive technology. Conclusion Micronutrient deficiencies were near-universal and largely undetected in this cohort. Supplementation was associated with a 74.1% clinical pregnancy rate. These hypothesis-generating findings support routine nutritional screening in the idiopathic infertility workup, pending larger randomised trials with live-birth endpoints.