ArticleBMC pregnancy and childbirth2022
Preconception vitamin D intake and obstetric outcomes in women using assisted reproductive technology: the Japan Environment and Children's Study.
Article in BMC pregnancy and childbirth, 2022. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 4 papers.
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4 citing papers in PubMed, 9 citations in OpenAlex.
- Effect of pre-conception serum vitamin D level on pregnancy outcomes in women undergoing in vitro fertilization with fresh embryo transfer: a retrospective analysis.Reproductive biology and endocrinology : RB&E · 2025Article
- Review
- Predicting postpartum hemorrhage in women undergoing planned cesarean section: A multicenter retrospective cohort study in Japan.PloS one · 2024Article
- Article
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15 authors at 2 institutions in 1 country.
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Abstract
backgroundIn reproductive medicine, vitamin D (VitD) is of particular interest because its deficiency has been linked to various infertility issues. Thus, preconception care, including appropriate VitD supplementation, is essential, especially in women using assisted reproductive technology (ART). Despite the therapeutic benefits of VitD, adverse events due to a high daily intake may influence obstetric outcomes. However, the effects of either low or high preconception VitD intake on obstetric outcomes, including the outcomes in women who used ART, remain unclear. Therefore, the aim of this study was to examine the association between pre-pregnancy daily VitD intake and obstetric outcomes in Japanese women, including those who conceived through ART.
methodsData were obtained from the Japan Environment and Children's study database comprising 92,571 women recruited between January 2011 and March 2014 in Japan. Participants were categorized into five quintiles according to pre-pregnancy VitD intake (Q1 and Q5 had the lowest and highest VitD intake, respectively) and stratified according to the use of ART. Multiple logistic regression was performed to identify the effects of pre-pregnancy VitD intake on preterm birth (PTB), low-birth weight infant (LBW), and small for gestational age (SGA).
resultsUsing Q3 (middle VitD intake) as a reference, our analysis revealed that Q5 (highest VitD intake) showed an increased risk of LBW < 1500 g (adjusted odds ratio [aOR]: 1.09, 95% confidence interval [CI]: 1.00-1.18) and SGA (aOR: 1.26, 95% CI: 1.14-1.39) among women who conceived without ART. Among women who conceived with ART, we found that Q5 (highest VitD intake) showed an increased risk of PTB at < 37 weeks (aOR: 2.05, 95% CI: 1.27-3.31).
conclusionThe present study revealed that higher VitD intake before pregnancy may affect perinatal outcomes, particularly in women using ART. Our findings may facilitate personalized preconceptional counseling regarding VitD intake based on the method of conception, especially among women using ART.
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