Systematic review and meta-analysis of vitamin D deficiency in different pregnancy on preterm birth

Abstract

Background: Current studies suggest that vitamin D deficiency during pregnancy can produce a certain effect for preterm birth (PTB), but there is no research showing whether vitamin D deficiency has a consistent effect in different pregnancies; thus, we conducted a systematic review and meta-analysis of 24 observational studies, grouping them according to the gestational age at the time of serum sampling, to investigate whether vitamin D deficiency in different periods of gestation has different effects on PTB and to provide an evidence-based basis for pregnant women to measure and supplement vitamin D. Methods: The databases PubMed-Medline, EMBASE, the Cochrane Library, Web of Science, EBSCO, CBM, and CNKI were searched until February 2020. Two researchers independently assessed the eligibility and quality of studies, and STATA 12.0 software was used for meta-analysis. Result: Seven cohort studies, 13 case–control studies, and 4 cross-sectional studies were included from 2500 articles by inclusion and exclusion criteria. After adjusting for age, race, and other confounding factors, meta-analysis results showed that vitamin D deficiency in the first trimester, the second trimester, and the third trimester did not increase the risk of PTB (odds ratio (OR) = 1.01, 95% confidence interval (CI) (0.88, 1.16), P = .867; OR = 1.12, 95%CI (0.92, 1.37), P = .249; OR = 1.05, 95%CI (0.87, 1.27), P = .602). However, there was moderate heterogeneity in the study of vitamin D deficiency in the second trimester, and subgroup analysis suggested that vitamin D deficiency in the second trimester may increase the risk of PTB (OR = 1.33, 95%CI (1.15, 1.54), P = .000). A sensitivity analysis of the second trimester showed that excluding any 1 study did not significantly change the results. Conclusions: Vitamin D deficiency in early and late pregnancy may not be associated with PTB, while vitamin D deficiency in middle pregnancy is likely to have an important effect on PTB. Vitamin D levels should be measured in the second trimester of pregnancy, and vitamin D supplements should be provided if necessary.

Periodontal Disease and Vitamin D Deficiency in Pregnant Women: Which Correlation with Preterm and Low-Weight Birth?

“…D sufficiency in the second and third trimesters was associated with higher gestational duration. Similar results were shown in a recent metanalysis on 24 studies [ 95 ]. The authors reported that vitamin D deficiency in the second trimester is likely associated with an increased risk of PTB with an odds ratio of 1.12.…”

“…Moreover, the elevated demand for micronutrients during pregnancy leads to women being at high risk of vitamin D deficiency and periodontal disease; thus, adequate vitamin D supplementation plays a crucial role in pregnant women to reduce the risk of periodontal disease, and even the risk of PTB and LBW in newborns [ 95 , 99 , 100 ].…”

Association between Maternal Serum 25-Hydroxyvitamin D Concentrations and the Risk of Preterm Birth in Central Sudan: A Case–Control Study

“…On the other hand, several previous studies did not identify an association between low serum 25(OH)D concentrations/vitamin D deficiency and the risk of PB [18][19][20][21]. Recently, Lian et al, in their meta-analysis which included 24 studies, concluded that vitamin D deficiency in early and late pregnancy was not associated with increased risk of PB; however, they reported that vitamin D deficiency in the second trimester of pregnancy was associated with increased risk of PB [17]. It is worth mentioning that a recent meta-analysis which included 55 studies showed that only a relatively high (<75 nmol/L) cut-off level of vitamin D was associated with PB [26].…”

“…Previous reports have shown that several maternal and perinatal adverse effects such as gestational diabetes, preeclampsia, PB and small for gestation age and intrauterine growth restriction are associated with low vitamin D levels in pregnancy [10,11]. Previous studies on the associations between vitamin D and Nutrients 2022, 14, 891 2 of 8 PB showed inconclusive results-while some of the studies showed that serum vitamin D levels are lower in women with PB and reported that vitamin D deficiency is associated with an increased risk of PB [10][11][12][13][14][15][16], other studies did not identify an association between low serum 25(OH)D concentrations/vitamin D deficiency and the risk of PB [17][18][19][20][21]. Moreover, most of these studies were conducted in countries outside Africa, with few published data on the association between serum 25(OH)D concentrations/vitamin D deficiency and the risk of PB in Africa [13,14].…”

Pregnancy and COVID-19: The Possible Contribution of Vitamin D

“…Different works suggested vitamin D deficiency during pregnancy could produce an effect on PTB [19][20][21]: A systematic review and meta-analysis of 24 observational studies was performed to clarify this topic. On one hand, a study highlighted vitamin D deficiency during gestation did not increase the risk of PTB.…”