ArticleBMC pregnancy and childbirth2020
Association between pre-pregnancy calcium intake and hypertensive disorders during the first pregnancy: the Japan environment and children's study.
Article in BMC pregnancy and childbirth, 2020. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 13 papers, 2 of them syntheses that pooled it.
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Who cites it
13 citing papers in PubMed, 2 syntheses or guidelines pooled it, 34 citations in OpenAlex.
- Calcium Supplementation in Pregnancy: A Systematic Review of Clinical Studies.Medicina (Kaunas, Lithuania) · 2025Pooled it
- Association of parathyroid hormone with risk of hypertension and type 2 diabetes: a dose-response meta-analysis.BMC cardiovascular disorders · 2024Pooled it
- Pre-pregnancy body mass index range and prevalence of hypertensive disorders of pregnancy: the Japan environment and children's study.BMC pregnancy and childbirth · 2025Article
- Maternal Dietary Zinc Intake during Pregnancy and Childhood Allergic Diseases up to Four Years: The Japan Environment and Children's Study.Nutrients · 2023Article
- Article
- Secondhand smoke exposure is associated with the risk of hypertensive disorders of pregnancy: the Japan Environment and Children's Study.Hypertension research : official journal of the Japanese Society of Hypertension · 2023Article
- Dietary calcium intake was related to the onset of pre-eclampsia: The TMM BirThree Cohort Study.Journal of clinical hypertension (Greenwich, Conn.) · 2023Article
- Article
- Gestational weight gain as a risk factor for dystocia during first delivery: a multicenter retrospective cohort study in Japan.BMC pregnancy and childbirth · 2022Article
- Hypertensive disorders of pregnancy: definition, management, and out-of-office blood pressure measurement.Hypertension research : official journal of the Japanese Society of Hypertension · 2022Review
- Article
- Adverse obstetric outcomes in early-diagnosed gestational diabetes mellitus: The Japan Environment and Children's Study.Journal of diabetes investigation · 2021Article
- Immunoglobulin E levels and pregnancy-induced hypertension: Japan Environment and Children's Study.Scientific reports · 2021Article
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Authors and funding
15 authors at 2 institutions in 1 country.
Funding
No grant is acknowledged in the PubMed record.
Abstract
backgroundDetermining the appropriate preconception care to reduce the occurrence of hypertensive disorder of pregnancy (HDP) remains a challenge in modern obstetrics. This study aimed to examine the association between pre-pregnancy calcium (Ca) intake and HDP in normotensive primiparas.
methodsWe used data from the Japan Environment Children's study (JECS), which is the largest birth cohort study. A total of 33,894 normotensive Japanese primiparas were recruited for JECS between January 2011 and March 2014. Participants were categorized into five groups according to pre-pregnancy Ca intake quintiles (Q1 and Q5 were the lowest and highest Ca intake groups, respectively) to compare their basic background and obstetrics outcome. Multiple logistic regressions were performed to identify the effect of pre-pregnancy Ca intake on HDP, early onset HDP, and late-onset HDP, using Ca intake thresholds of 500, 550, 650, 700, 1000, 1500, and 1500 mg.
resultsWe found significant differences in maternal background among the Ca intake groups; in particular, there were more participants with low socioeconomic status, indicated by low education level and low household income, and smokers in the lowest Ca intake group. Multiple logistic regression did not show any significant difference with regard to HDP, early onset HDP, and late-onset HDP in each Ca intake threshold.
conclusionsDespite considerable recommendations concerning Ca intake for women of reproductive age, the present study indicates that pre-pregnancy Ca intake was not associated with an increased risk of new-onset hypertension among primiparas during pregnancy. Further studies examining the effect of other pre-pregnancy dietary factors on obstetric outcomes should be considered in the formulation of earlier preventive strategies for primiparas.
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