Maternal serum vitamin D levels and preterm delivery among low-risk parturients in Lagos, Nigeria

Vitamin D Metabolites in Mother-Infant Dyads and Associated Clinical Outcomes in a Population of Nigerian Women

Low levels of vitamin D in maternal and cord blood have been associated with neonatal sepsis. This study assessed the association of vitamin D metabolites (25(OH)D, 3-epi-25(OH)D3, and 24,25(OH)2D3) levels in maternal and cord blood with newborn sepsis evaluation in Nigerian mother-infant dyads. Maternal and cord blood from 534 mothers and 536 newborns were processed using liquid chromatography-tandem mass spectrometry. Spearman correlation was used to compare continuous variables, Mann-Whitney for dichotomous variables, and Kruskal-Wallis for two or more groups. High cord percent 3-epi-25(OH)D3 levels were positively associated with newborn evaluation for sepsis (p = 0.036), while maternal and cord 25(OH)D and 24,25(OH)2D3 levels were not. Being employed was positively associated with maternal and newborn 3-epi-25(OH)D3 concentrations (p = 0.007 and p = 0.005, respectively). The maternal 3-epi-25(OH)D3 and percent 3-epi-25(OH)D3 were positively associated with vaginal delivery (p = 0.013 and p = 0.012, respectively). Having a weight-for-age Z-score ≤ -2 was positively associated with newborn percent 3-epi-25(OH)D3 levels (p = 0.004), while a weight-for-length Z-score ≤ -3 was positively associated with maternal and newborn percent 3-epi-25(OH)D3 levels (p = 0.044 and p = 0.022, respectively). Our study highlights the need to further investigate the biological role of 3-epi-25(OH)D3 and its clinical significance in fetal growth and newborn outcome.

Post Hoc Analysis of National Institute of Child Health and Human Development Vitamin-D Pregnancy Cohort and The Role of Functional Vitamin-D Deficiency in Pregnancy

OBJECTIVE

 Our objective was to conduct a secondary, post hoc analysis of the National Institute of Child Health and Human Development (NICHD) vitamin D (vitD) pregnancy study by Hollis et al, which reported on the effect of vitD supplementation in pregnant women and determine the potential interaction between intact parathyroid hormone (iPTH) concentrations, vitD status, and various comorbidities associated with pregnancy. Women with low 25-hydroxy vitamin D (25(OH)D) concentrations and high iPTH concentrations during pregnancy, known as functional vitamin-D deficiency (FVDD), were more likely to acquire complications also affecting their neonates.

STUDY DESIGN

 This post hoc analysis of data collected from a diverse group of pregnant women participating in the NICHD vitD pregnancy study was applied to investigate the applicability of the concept of FVDD in pregnancy (Hemmingway, 2018) in identifying potential risks for certain comorbidities of pregnancy. This analysis defines FVDD as maternal serum 25(OH)D concentrations below 20 ng/mL and iPTH concentrations above 65 pg/mL creating a definitive ratio number, 0.308, to classify mothers as having FVDD prior to delivery (PTD). Statistical analyses were performed using SAS 9.4 (Cary, NC).

RESULTS

 In total, 281 women (85 African American, 115 Hispanic, and 81 Caucasian) with 25(OH)D and iPTH concentrations measured at monthly visits were included in this analysis. No statistically significant association was found between mothers classified as having FVDD at baseline or 1-month PTD and hypertensive disorders of pregnancy, infection, or admittance to the neonatal intensive care unit. When combining all comorbidities of pregnancy in this cohort, results showed those with FVDD at baseline, 24 weeks' gestation, and 1-month PTD were more likely to experience a comorbidity (p = 0.001; p = 0.001; p = 0.004, respectively). Those with FVDD 1-month PTD were 7.1 times (confidence interval [CI]: 1.71-29.81) more likely to have preterm birth (<37 weeks) than women without FVDD.

CONCLUSION

 Participants were more likely to have experienced preterm birth if they met the criteria for FVDD. This study supports the importance of FVDD during pregnancy.

KEY POINTS

· Functional vitamin D deficiency (FVDD) is defined as the ratio of 25(OH)D divided by iPTH concentration ≤0.308.. · At a minimum, it is recommended that vitamin D status be kept in the healthy range based on current recommendations for pregnant individuals.. · FVDD is a more sensitive predictor of pregnancy risk than 25(OH)D alone.. · FVDD identified those with greater risk of preterm birth in this cohort..

Development and internal validation of a clinical prediction model for spontaneous abortion risk in early pregnancy

OBJECTIVE

This study aimed to develop and internally validate a prediction model for estimating the risk of spontaneous abortion in early pregnancy.

METHODS

This prospective cohort study included 9,895 pregnant women who received prenatal care at a maternal health facility in China from January 2021 to December 2022. Data on demographics, medical history, lifestyle factors, and mental health were collected. A multivariable logistic regression analysis was performed to develop the prediction model with spontaneous abortion as the outcome. The model was internally validated using bootstrapping techniques, and its discrimination and calibration were assessed.

RESULTS

The spontaneous abortion rate was 5.95% (589/9,895) 1. The final prediction model included nine variables: maternal age, history of embryonic arrest, thyroid dysfunction, polycystic ovary syndrome, assisted reproduction, exposure to pollution, recent home renovation, depression score, and stress score 1. The model showed good discrimination with a C-statistic of 0.88 (95% CI 0.87‒0.90) 1, and its calibration was adequate based on the Hosmer-Lemeshow test (p = 0.27).

CONCLUSIONS

The prediction model demonstrated good performance in estimating spontaneous abortion risk in early pregnancy based on demographic, clinical, and psychosocial factors. Further external validation is recommended before clinical application.

The effect of vitamin D on the severity of dysmenorrhea and menstrual blood loss: a randomized clinical trial

BACKGROUND

Primary dysmenorrhea is considered as one of the women's main problems during reproductive age. The present study aimed to investigate the effect of vitamin D on the severity of dysmenorrhea and menstrual blood loss.

METHODS

This double-blind, randomized, placebo-controlled trial, was performed on 84 single female college students between 18 and 25 years old who living in dormitories. Students with primary dysmenorrhea and vitamin D deficiency were divided into experimental (n = 42) and control (n = 42) groups. Five days before the putative beginning of their next menstrual cycle, the experimental group received 300,000 IU vitamin D (50,000 IU, two tablets every 8 h), and the control group received a placebo (oral paraffin). The effects of the supplement on the severity of dysmenorrhea and menstrual blood loss were evaluated one cycle before and during two successive cycles. Using the visual analog scale (VAS), verbal multidimensional scoring system (VMS), and pictorial blood assessment chart (PBLAC) questionnaires. Fisher's exact, Chi-square, independent sample t-test and repeated measurements were used.

RESULTS

In total, 78 of the 84 students completed the study (39 students per group). The intervention resulted in a significant reduction in the mean scores of both the VAS and VMS in the experimental group, in the first and second menstrual cycles (p < 0.001, p < 0.001, respectively), but not in the means score of PBLAC. Mefenamic acid consumption at the first and second menstruation period, in the experimental group was lower than the control group (p = 0.009, p < 0.001, respectively).

CONCLUSIONS

The results indicate that vitamin D supplementation could decrease the severity of primary dysmenorrhea and the need to consume pain-relief medications. Contrariwise vitamin D supplementation had no significant effect on menstrual blood loss.

TRIAL REGISTRATION

This trial was registered in the Iranian Registry of Clinical Trials with code IRCT201305212324N on 18/1/2014. URL of registry: https://en.irct.ir/trial/1964 .

A Scoping Review of Preterm Births in Sub-Saharan Africa: Burden, Risk Factors and Outcomes

Preterm births (PTB) are the leading cause of neonatal deaths, the majority of which occur in low- and middle-income countries, particularly those in Sub-Saharan Africa (SSA). Understanding the epidemiology of prematurity is an essential step towards tackling the challenge of PTB in the sub-continent. We performed a scoping review of the burden, predictors and outcomes of PTB in SSA. We searched PubMed, Embase, and three other databases for articles published from the database inception to 10 July 2021. Studies reporting the prevalence of PTB, the associated risk factors, and/or its outcomes were eligible for inclusion in this review. Our literature search identified 4441 publications, but only 181 met the inclusion criteria. Last menstrual period (LMP) was the most commonly used method of estimating gestational age. The prevalence of PTB in SSA ranged from 3.4% to 49.4%. Several risk factors of PTB were identified in this review. The most frequently reported risk factors (i.e., reported in ≥10 studies) were previous history of PTB, underutilization of antenatal care (<4 visits), premature rupture of membrane, maternal age (≤20 or ≥35 years), inter-pregnancy interval, malaria, HIV and hypertension in pregnancy. Premature babies had high rates of hospital admissions, were at risk of poor growth and development, and were also at a high risk of morbidity and mortality. There is a high burden of PTB in SSA. The true burden of PTB is underestimated due to the widespread use of LMP, an unreliable and often inaccurate method for estimating gestational age. The associated risk factors for PTB are mostly modifiable and require an all-inclusive intervention to reduce the burden and improve outcomes in SSA.

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

There are few published studies on the association between vitamin D concentrations and preterm birth (PB) in sub-Saharan Africa. The current study aimed to assess the association between 25-hydroxyvitamin D (25[OH)] D) levels and PB. A matched case–control study (60 women in each arm) was conducted in Medani maternity hospital in central Sudan. The cases were women with spontaneous PB, and healthy women with term deliveries were the controls. The clinical/medical and obstetric history was gathered using a questionnaire. The enzyme-linked immunosorbent assay was used to measure the serum 25(OH)D levels. Women with PB had significantly lower median (interquartile range) 25(OH)D concentrations compared with the controls (18.4 (7.3) ng/mL vs. 20.2 (16.5) ng/mL, p = 0.001). Forty-two (70.0%) women with PB and 29 (48.3%) women in the control group had vitamin D deficiency (25(OH)D level ≤ 20 ng/mL). The results of the multivariable logistic regression showed that the 25(OH)D concentrations were negatively associated with PB (adjusted odds ratio (aOR) = 0.92, 95% confidence interval (CI) = 0.87–0.97). Vitamin D-deficient pregnant women were at a higher risk of PB (aOR = 2.69, 95% CI = 1.17–6.23). Low 25(OH)D concentrations were found at the time the variable was determined in women with spontaneous PB and were an independent risk factor for PB.

Second-trimester 25-hydroxyvitamin D status in pregnant women from southern China and risk of macrosomia: a large-scale retrospective cohort study

PURPOSE

The association between maternal vitamin D concentrations and birth weight is controversial. We conducted a large-scale retrospective cohort study in southern China to explore this relationship.

METHODS

From July 2017 to April 2019, we enrolled 10,586 pregnant women and measured serum vitamin D [via 25-hydroxyvitamin D, 25(OH)D] in the second trimester using electrochemiluminescence immunoassays. The association between macrosomia and 25(OH)D was analyzed using logistic regression and ROC curve.

RESULTS

Average vitamin D concentration was 61.1 ± 20.2 nmol/L. Additionally, 31.1% participants had 25(OH)D concentrations <50.0 nmol/L, while 68.9% exhibited concentrations ≥50.0 nmol/L. Of the subjects, 3.2% of women delivered macrosomic infants (neonatal birth weight ≥4000 g) and 96.8% did not. The macrosomia group had lower vitamin D concentrations than the non-macrosomia group (59.5 ± 22.3 vs. 61.2 ± 20.1, p < .05). Approximately a third of each group had vitamin D < 50.0 nmol/L (non-macrosomia, 31.3%; macrosomia, 35.9%; p = .055). After adjusting for confounding variables, women with 25(OH)D ≥ 50.0 nmol/L had 24.3% lower macrosomia risk than women with 25(OH)D < 50.0 nmol/L (adjusted OR = 0.757, 95% CI = 0.599-0.956, p = .0193). The predictive accuracy of vitamin D concentrations for evaluating macrosomia risk was 0.667 area under the ROC curve.

CONCLUSION

Maternal vitamin D levels are negatively correlated with macrosomia. Elevating vitamin D above 50.0 nmol/L may reduce macrosomia incidence.

High prevalence of vitamin D deficiency among normotensive and hypertensive pregnant women in Ghana

BACKGROUND

Hypovitaminosis D in pregnancy is associated with adverse health outcomes in mothers, newborns and infants. This study assessed the levels of 25-hydroxyvitamin D [25(OH)D] in normotensive pregnancies and in preeclampsia, evaluated the association between vitamin D deficiency and preeclampsia risk; and determined the foeto-maternal outcome in preeclamptic women with vitamin D deficiency.

METHODS

This case-control study was conducted among pregnant women who visited the Comboni Hospital, in Ghana from January 2017 to May 2018 for antenatal care. A total of 180 pregnant women comprising 88 preeclamptic women (PE) and 92 healthy normotensive pregnant women (NP) were recruited. Socio-demographic, clinical and obstetric data were obtained using validated questionnaires. Blood pressure and anthropometrics were measured, and blood samples were collected for the estimation of 25- hydroxyvitamin D [25(OH)D] using enzyme-linked immunosorbent assay technique. Lipids (total cholesterol, triglycerides, HDL-cholesterol and LDL-cholesterol) were also estimated.

RESULTS

A total of 81.7% of the study participants had vitamin D deficiency. Of these, 88.6% of the women with PE had vitamin D deficiency compared to 75.0% in the NP. Vitamin D levels were significantly reduced in the PE women compared to the normotensive pregnant women (p = 0.001). A higher proportion of the preeclamptic women who were vitamin D deficient had preterm delivery (p < 0:0001) and delivered low birth weight infants (p < 0:0001), and infants with IUGR (p < 0:0001) compared to the control group (p < 0:0001). Pregnant women with PE presented with significant dyslipidemia, evidenced by significantly elevated TC (p = 0.008), LDL (p < 0.0001), triglycerides (p = 0.017) and a significantly reduced HDL (p = 0.001) as compared to NP. In the preeclamptic women, serum 25(OH) D showed an inverse, but not significant association with TC (β = - 0.043, p = 0.722, TG (β = - 0.144, p = 0.210) and LDL (β = - 0.076, p = 0.524) and a positive, but not significant association with HDL (β = 0.171, p = 0.156).

CONCLUSION

The prevalence of vitamin D deficiency is high in both normotensive pregnancies and pregnancies complicated by preeclampsia but amplified in preeclampsia. Higher proportion of pregnant women with hypovitaminosis D had preterm babies and delivered low birth weight neonates. Additional studies are needed to explore the potential benefits and optimal dosing of vitamin D use in pregnancy, especially in sub-Saharan Africa.

Exploration of strategic food vehicles for vitamin D fortification in low/lower-middle income countries

We previously identified 7 low/lower-middle income countries (LMICs; Afghanistan, Pakistan, India, Mongolia, Yemen, Nigeria, Tunisia) which have excess burden of vitamin D deficiency and could benefit enormously from food fortification with vitamin D. A key challenge is finding a suitable industrially-manufactured food vehicle that is consumed in sufficient amounts by the population at-risk. We used FAO Food Balance Sheet data (from 2003-2013) to model the potential impact of four different food vehicles (edible plant-based oil, wheat flour, maize flour, and milk), and at different addition levels, on the average per capita vitamin D supply in all 7 LMICs. Daily per capita supply for ˜95 foods was calculated and vitamin D supply determined using dietary analysis software with no addition and following stepwise additions of vitamin D to the four food vehicles. The daily per capita vitamin D supply without fortification ranged from 0.4 to 3.3 μg (≤2 μg/d in six LMICs). We applied a vitamin D intake of 5 μg/d as a benchmark because it maintains serum 25-hydroxyvitamin D ≥ 25 nmol/L in ˜90% of individuals. Modelling showed that fortifying edible oil with vitamin D at the 7.5 μg/100 g (guideline) and 15 μg/100 g levels allowed vitamin D supply in 1 and 3 of the 7 LMICs, respectively, to attain ≥5 μg/d (range: 5.8-11.0 μg/d). Fortifying milk at the 1.0 μg/100 g and 2.0 μg/100 g guideline levels, allowed 2 and 3 LMICs, respectively, to attain ≥5 μg/d (range: 5.2-9.8 μg/d). Fortifying wheat flour at the 1.4 μg/100 g (guideline) and 2.8 μg/100 g allowed 5 and 6 LMICs, respectively, to attain ≥5 μg/d (range: 5.3-18.6 μg/d). Maize flour had low impact due to consumption levels. In conclusion, using these levels of addition, at least one food vehicle was able to increase per capita vitamin D supply to ≥5 μg/d in each of the LMICs.

Protective effects of vitamin D against injury in intestinal epithelium

BACKGROUND

Vitamin D deficiency is associated with intestinal barrier dysfunction, which contributes to pathogenesis of acute intestinal injury in children. We aim to investigate the effects of vitamin D on intestinal injury in intestinal epithelial cells and organoids.

METHODS

Lipopolysaccharide (LPS) was used to induce injury in intestinal epithelial cells (IEC-18) and organoids, and the effect of vitamin D was assessed. Cell viability was measured and inflammation cytokines TNFα and IL-8 were quantified. FITC-dextran 4 kDa (FD4) permeability was measured using Transwell while tight junction markers were assessed by immunofluorescence staining in IEC-18 and intestinal organoids. Data were compared using one-way ANOVA with Bonferroni post-test.

RESULTS

IEC-18 viability was decreased by LPS treatment, but was prevented by vitamin D. The upregulation of inflammation was inhibited by vitamin D, which also decreased epithelium permeability. Vitamin D restored tight junction ZO-1 and claudin 2. In addition, vitamin D decreased TNFα expression and prevented the disruption of ZO-1 in injured organoids.

CONCLUSIONS

Vitamin D rescued epithelial barrier function by improving permeability and restoring tight junctions, leading to decrease inflammation. This study confirms the protective effects of vitamin D, which could be used as a treatment strategy for infants at risk of developing intestinal injury.