Maternal Serum Vitamin Research Articles

Evaluation of maternal serum folate, vitamin B12, and homocysteine levels andfactor V Leiden, factor II g.20210G>A, and MTHFR variations in prenatallydiagnosed neural tube defects.

Neural tube defects (NTDs) are common congenital malformations that develop as a result of interactions between several genes and environmental factors. Many factors have been investigated in order to understand the etiology of NTDs, and many studies have identified folate intake as a common contributing factor. The exact etiology of the disease is still unknown. In this study, we compared serum folate, vitamin B12, and homocysteine levels, along with common thrombophilia-related genetic variations, including factor V Leiden, factor II g.20210G>A, MTHFR c.677C>T, and MTHFR c.1298A>C, in 35 pregnant women with fetal NTDs and 38 pregnant women with healthy fetuses. A significant difference in serum vitamin B12 level and factor V Leiden frequency was detected between the two groups. On the other hand, serum folate, homocysteine levels, and factor II g.20210G>A, MTHFR c.677C>T, and MTHFR c.1298A>C were not significantly different in the NTD group compared to the controls. These results indicate that vitamin B12 supplementation along with folate may help in lowering NTD frequency. In addition, this is the first study that provides evidence for a possible relationship between increased NTD risk and factor V Leiden.

The clinical relevance of maternal serum HCY, folic acid and vitamin B12 levels with pregnancy induced hypertension

Objective To evaluate the clinical relevance of maternal serum HCY, folic acid (FA) and vitamin B12 (VB12) levels with pregnancy induced hypertension (PIH). Methods 100 pregnant women with PIH were selected as the observation group.100 non-PIH pregnant women at the same period in our hospital were selected as control group.Serum HCY, FA and VB12 levels at trimester, second trimester and third trimester of pregnancy were detected and compared. Results HCY levels at trimester, second trimester and third trimester of pregnancy were (15.07±4.86)μmol/L, (17.82±3.16)μmol/L and (19.25±3.24)μmol/L in the observation group, those were (6.36±2.47)μmol/L, (5.89±2.14)μmol/L and (6.68±2.08)μmol/L in the control group, prenatal HCY levels of the observation group in the three stages were significantly higher (t=15.97, 31.26, 15.97, all P 0.05). FA levels in the observation group at second trimester and third trimester were significantly lower than the control group (t=8.95, 11.06, all P<0.05). VB12 levels at three stages of prenatal in the observation group were significantly lower than the control group (t=4.23, 2.53, 4.23, all P<0.05). Conclusion Serum FA and VB12 levels are deficiency at second trimester and third trimester in PIH pregnant women, and with HCY rising, which may associated with the occurance and development of PIH. Key words: Pregnancy induced hypertension; Cysteine; Folic acid; Vitamin B12

Electronic Poster Presentations, Maternal Fetal Medicine

Electronic Poster Presentations, Maternal Fetal Medicine

The effects of maternal vitamin D on neonatal growth parameters.

Vitamin D facilitates calcium absorption and bone building. Presence of vitamin D is highly important in pregnant women due to its effect on the development of the fetal skeleton. The study population comprised 208 low-risk pregnant women of a heterogeneous population. Maternal and fetal serum concentrations of vitamin D were measured using the Liaison 25(OH)D Assay (DiaSorin, Italy). Maternal vitamin D serum concentrations correlate with neonatal vitamin D serum concentrations but do not affect neonatal weight and/or head circumference. WHAT IS KNOWN? • Vitamin D is known to be also involved in immunomodulation and cellular proliferation and differentiation. • Vitamin D is highly important in pregnant women for its effect on fetal musculoskeletal and neurological development. WHAT IS NEW? • No association was detected between maternal or neonatal vitamin D concentration with neonatal growth parameters or obstetrical complications, and no association was found between maternal vitamin D serum concentrations and maternal obstetrical complication rate. • A strong correlation was demonstrated between maternal and neonatal serum vitamin D concentrations.

Early pregnancy maternal vitamin D concentrations and risk of gestational diabetes mellitus.

While associations of vitamin D deficiency with type 2 diabetes have been well demonstrated, investigations of vitamin D and risk of gestational diabetes mellitus (GDM) reported inconsistent findings. We examined associations of vitamin D status with GDM. In a nested case-cohort study (135 GDM cases and 517 non-GDM controls), we measured maternal serum vitamin D status (total 25[OH]D and 25[OH]D3 ) in early pregnancy (16 weeks on average) using liquid chromatography-tandem mass spectroscopy. GDM was diagnosed according to the American Diabetes Association guidelines. We calculated adjusted odds ratios and 95% confidence intervals (CIs) using logistic regression models. GDM cases had lower mean total 25[OH]D (27.3 vs. 29.3 ng/mL) and 25[OH]D3 (23.9 vs. 26.7 ng/mL) concentrations compared with women who did not develop GDM (both P-values < 0.05). Overall, 25[OH]D3 concentrations, but not total 25[OH]D concentrations, were significantly associated with GDM risk. A 5-ng/mL increase in 25[OH]D3 concentration was associated with a 14% decrease in GDM risk (P-value = 0.02). Women in the lowest quartile for 25[OH]D3 concentration had a twofold [95% CI 1.15, 3.58] higher risk of GDM compared with women in the highest quartile (P-value for trend < 0.05). Early pregnancy vitamin D status, particularly 25[OH]D3 , is inversely associated with GDM risk.

The Effect of Multi mineral-Vitamin D Supplementation on Pregnancy Outcomes in Pregnant Women at Risk for Pre-eclampsia.

Background:The objective of this study was to determine the favorable effects of multi mineral-Vitamin D supplementation on pregnancy outcomes among women at risk for pre-eclampsia.Methods:This randomized double-blind controlled clinical trial was conducted among 46 women at risk for pre-eclampsia at 27 weeks’ gestation with positive roll-over test. Pregnant women were randomly assigned to receive either the multi mineral-Vitamin D supplements (n = 23) or the placebo (n = 23) for 9-week. Multi mineral-Vitamin D supplements were containing 800 mg calcium, 200 mg magnesium, 8 mg zinc, and 400 IU Vitamin D3. Fasting blood samples were taken at baseline and after 9-week intervention to measure related factors. Newborn's outcomes were determined.Results:Although no significant difference was seen in newborn's weight and head circumference between the two groups, mean newborns’ length (51.3 ± 1.7 vs. 50.3 ± 1.2 cm, P = 0.03) was significantly higher in multi mineral-Vitamin D group than that in the placebo group. Compared to the placebo, consumption of multi mineral-Vitamin D supplements resulted in increased levels of serum calcium (+0.19 vs. −0.08 mg/dL, P = 0.03), magnesium (+0.15 vs. −0.08 mg/dL, P = 0.03), zinc (+8.25 vs. −21.38 mg/dL, P = 0.001) and Vitamin D (+3.79 vs. −1.37 ng/ml, P = 0.01). In addition, taking multi mineral-Vitamin D supplements favorably influenced systolic blood pressure (SBP) (−1.08 vs. 6.08 mmHg, P = 0.001) and diastolic blood pressure (DBP) (−0.44 vs. 3.05 mmHg, P = 0.02).Conclusions:Multi mineral-Vitamin D supplementation for 9-week in pregnant women at risk for pre-eclampsia resulted in increased newborn's length, increased circulating levels of maternal serum calcium, magnesium, zinc and Vitamin D, and led to decreased maternal SBP and DBP.

Maternal serum vitamin D levels in pregnancies complicated by neural tube defects

Objective: The association between vitamin D deficiency and abnormal neural development has been proposed previously. We aimed to evaluate maternal serum vitamin D levels in pregnancies complicated by neural tube defects (NTDs) and compared them with healthy pregnant women.Methods: A total of 60 pregnant women were included in this controlled cross-sectional study. Thirty of the patients whose pregnancies were complicated by meningocele, meningomyelocele, encephalocele, anencephaly and fetal acrania constituted the study group, whereas 30 normal pregnant women constituted the control group. The main parameters recorded for each woman were as follows: age, body mass index (BMI), gestational week (GW), gravidity, abortion, co-morbidities, dressing style, consumption of milk and dairy products and serum levels of 25(OH)VitD3, calcium, albumin and total protein.Results: The mean maternal serum 25(OH)VitD3 level was 6.2 ± 5.0 ng/ml in the study group and 9.1 ± 7.3 ng/ml in the control group (p: 0.071). The mean maternal serum calcium level was statistically significantly higher in the control group, and calcium-rich dietary intake was also more common in this group (p < 0.05). There was no statistically significant difference between groups in terms of age, BMI, GW, dressing style and serum levels of albumin and total protein.Conclusions: Vitamin D deficiency is common among pregnant women, and maternal serum calcium levels were lower in pregnancies complicated by NTD than healthy pregnant women. Larger further studies are required to evaluate the effects of calcium-rich dietary sources or vitamin D and calcium in the development of NTDs.

The relationship between low maternal serum vitamin D levels and glycemic control in gestational diabetes assessed by HbA1c levels: an observational cross-sectional study

BackgroundA great association between vitamin D deficiency and type 2 diabetes mellitus has been suggested in literature. During pregnancy, this deficiency is even more critical. It appears that vitamin D insufficiency during pregnancy may be associated with maternal hazards. The aim of this study was to assess the relation between the levels of 25-hydroxy-cholecalciferol (vitamin D), and the glycemic control in pregnant women.MethodsAn observational cross-section study including 160 pregnant women between 20-40 years in age, in their third trimester, divided into two equal groups. First group consisted of 80 women with established diagnosis of gestational diabetes and the second group with proved normal blood glucose levels. We assessed vitamin D in serum, fasting blood glucose, serum insulin and glycosylated hemoglobin (HbA1c) levels and we depicted the insulin sensitivity using the Quantitative insulin sensitivity check index (Quicki). The results were collected and statistically correlated.ResultsThe mean vitamin D levels were 46.61 ± 6.087 and 47.25 ± 10.181in controls and women with gestational diabetes mellitus (GDM) respectively. The fasting insulin levels were significantly higher in the group with GDM with a mean of 18.51 ± 6.44 compared to 8.95 ± 2.52 in the control group.The correlation coefficient (r) between HbA1c levels and Vitamin D level was -0.492 with a P value <0.05. Similar associations were also found with the fasting blood sugar levels (r = - 0.386) and with Quicki values (r = -0.250). Vitamin D levels correlated significantly with the fasting blood glucose, the fasting serum insulin and the HbA1c levels, the P value in all these correlations were <0.05. The P value with Quicki results was 0.064.ConclusionsThere is a statistically significant negative correlation between the glycemic control and vitamin D levels in serum in the whole study population. The effect of adequate vitamin D replacement on glycemic control was not studied in our work correlation. We suggest larger scale studies addressing this issue.

Vitamin B12 and folic acid status of term pregnant women and newborns in the Antwerp region, Belgium

Objective: Descriptive study on maternal serum vitamin B12 and folic acid in term pregnancy and in umbilical cord blood that was performed in an inner city hospital with a mixed ethnic population in the region of Flanders in Belgium. Materials and Methods: A prospective cohort study that took place from April 1 until May 31, 2011. Plasma folic acid and vitamin B12 were measured in maternal and umbilical cord blood from all term uncomplicated deliveries in a single regional hospital. Data on age, previous obstetric history, ethnicity, nutritional intake, and use of vitamin supplements were registered. Results: Data were collected from 110 patients, mean maternal serum vitamin B12 was 243.9 pmol/l and mean folic acid level was 43.0 nmol/l. Using a cutoff of respectively 150 pmol/l for vitamin B12 and 7.1 nmol/l for folic acid, 13% of the women were classified as vitamin B12-deficient and 23% were deficient for folic acid. Vitamin B12 deficiency was only seen in autochthonous Belgian women. A correlation between the maternal and umbilical cord levels was noted (R = 0.7 for vitamin B12, R = 0.85 for folic acid), but none of the umbilical cord levels demonstrated deficiency. Number of previous pregnancies and intake of supplements had no influence. Conclusion: Pregnant women in Antwerp, Belgium, frequently show vitamin B12 and folic acid deficiency, although a correlation exists with lower umbilical cord levels, the present limited data did not demonstrate any case of deficiency in umbilical cord blood. The frequency is highest in the autochthonous population and is not influenced by intake of vitamin supplements.

Serum vitamin B12 levels during the first trimester of pregnancy correlate with newborn screening markers of vitamin B12 deficiency.

Low maternal vitamin B12 status is a risk factor for various adverse pregnancy outcomes. Although vitamin B12 deficiency is not a primary target of newborn screening (NBS) programs, measurements of propionylcarnitine (C3) and its ratios with acetylcarnitine (C3/C2) and palmitoylcarnitine (C3/C16) may incidentally identify vitamin B12-deficient newborns. The objective of this study was to measure vitamin B12 levels in women during the first trimester of pregnancy, evaluate predictors of these concentrations, and study their relationship with newborn screening results. Vitamin B12 concentrations were evaluated in 204 women during the first trimester of pregnancy and possible confounding factors were analyzed. After giving birth, data of their newborns (189) were collected (sex, gestational age, birthweight) and the acylcarnitine profile obtained by tandem mass spectrometry during NBS was analyzed. To assess the effects of the variables on vitamin B12 serum concentrations and newborn screening markers, stepwise multiple linear regression models were used. The mean serum concentration of vitamin B12 was 370.8 pmol/L (502.4 pg/mL) (SD 142.81). Vitamin B12 concentrations were significantly lower in smokers (p=0.027), and in women with low meat consumption (p=0.040). There was a significant inverse correlation between mothers'’ vitamin B12 concentrations and their children’'s C3 (r=-0.24; p=0.001), C3/C2 (r=-0.23; p=0.002) and C3/C16 levels (r=-0.20; p=0.006). Newborn screening markers (C3, C3/C2, and C3/C16) present an inverse correlation with maternal vitamin B12 status in the first trimester of pregnancy. Regarding factors that may influence maternal serum vitamin B12 levels during the first trimester, smoking seems to have a negative effect, and meat consumption a positive effect.

Low maternal serum vitamin D during pregnancy and the risk for postpartum depression symptoms

Pregnancy is a time of vulnerability for vitamin D insufficiency, and there is an emerging literature associating low levels of 25(OH)-vitamin D with depressive symptoms. However, the link between 25(OH)-vitamin D status in pregnancy and altered risk of postnatal depressive symptoms has not been examined. We hypothesise that low levels of 25(OH)-vitamin D in maternal serum during pregnancy will be associated with a higher incidence of postpartum depressive symptoms. We prospectively collected sera at 18weeks gestation from 796 pregnant women in Perth (1989-1992) who were enrolled in the Western Australian Pregnancy Cohort (Raine) Study and measured levels of 25(OH)-vitamin D. Women reported postnatal depressive symptoms at 3days post-delivery. Women in the lowest quartile for 25(OH)-vitamin D status were more likely to report a higher level of postnatal depression symptoms than women who were in the highest quartile for vitamin D, even after accounting for a range of confounding variables including season of birth, body mass index and sociodemographic factors. Low vitamin D during pregnancy is a risk factor for the development of postpartum depression symptoms.

Serum Vitamin B12 and Folate Concentrations and the Effect of the Mediterranean Diet on Vulnerable Populations

Low vitamin B12 and folate levels in expectant mothers may lead to low stores in babies. The aim of this study was to determine the frequencies of vitamin B12 and folate deficiencies in pregnant women and neonates, and to assess the effect of maternal vitamin status on babies’ vitamin levels in the Aegean region of Turkey, where the Mediterranean diet (mainly fresh fruits and vegetables) is adopted. We studied 72 pregnant women and their singleton-term babies. Venous blood samples of expectant mothers were collected 1 h before delivery and cord blood of babies were obtained at birth. The mean vitamin B12 in maternal and cord blood serum was 163.1 ± 72.0 pg/mL and 146.2 ± 102.5 pg/mL, and the mean folate, 9.8 ± 4.8 ng/mL and 15.8 ± 3.8 ng/mL, respectively. There were statistically significant correlation between maternal and cord blood serum vitamin B12 (r = 0.61, P = .04) and folate levels (r = 0.65, P < .001). 70.8% of the mothers and 83.9% of the babies were vitamin B12 deficient (<200 pg/mL). Neither group showed folate deficiency. The mean level of vitamin B12 in mothers significantly varied by the type of diet (241.6 (72.1) pg/mL versus 155.9 (68.2) pg/mL; P = .012). Vitamin B12 deficiency in pregnant women and neonates may be a public health problem in our community. The Mediterranean diet in these vulnerable groups may be an aggravating factor for vitamin B12 deficiency. Prenatal screening of all expectant mothers, prenatal supplementation of vitamin B12, and an increase in animal-source food intake may improve expectant mother's vitamin B12 level.

Maternal Vitamin D Status and Risk of Pre-Eclampsia: A Systematic Review and Meta-Analysis

Although several studies have investigated the association between maternal serum vitamin D levels and risk of pre-eclampsia, findings are inconsistent. This systematic review and meta-analysis of published observational studies was conducted to summarize the evidence on the association between maternal serum vitamin D levels and risk of pre-eclampsia. PubMed, ISI (Web of science), SCOPUS, SCIRUS, Google Scholar, and EMBASE databases were searched to identify related articles published through December 2012. For systematic review, we found 15 articles that assessed the association between maternal serum vitamin D levels and risk of pre-eclampsia. The meta-analysis was done on 8 studies that reported odds ratios or relative risks for pre-eclampsia. Between-study heterogeneity was examined using Cochran's Q test and I(2). Subgroup analysis and meta-regression were used to find possible sources of heterogeneity. The meta-analysis on 8 relevant papers revealed an overall significant association between vitamin D deficiency and risk of pre-eclampsia; however, there was significant between-study heterogeneity (I(2) = 52.7%; P = .039). In the subgroup analysis, we found that the overall effect was significant for studies that defined vitamin D deficiency as 25(OH)D ≤ 50 nmol/L (20 ng/mL), but not for those that considered it as <38 nmol/L (15.2 ng/mL). The association was seen for "cohort or nested case-control studies" as well as for "cross-sectional or case-control studies" (2.78; 1.45-5.33; P = .002). When the analysis was done by study location, the associations remained significant only for studies that came from the United States. There was a significant relationship between vitamin D deficiency and increased risk of pre-eclampsia. Further studies are required, particularly in developing countries.

Maternal early-pregnancy vitamin D status in relation to linear growth at the age of 5–6 years: results of the ABCD cohort

Low vitamin D status during pregnancy may be associated with infant skeletal growth. However, evidence on the longer-term effect is limited. This study aims to assess the association between maternal vitamin D status in early pregnancy and markers of linear growth (height, leg length and relative leg length) of the child at age 5-6 years. A subsample of data from the Amsterdam Born Children and Development (ABCD) study was used. Ethnic Dutch pregnant women and their children (n=1208) were included. Maternal serum vitamin D level was determined at first antenatal visit (median 13 weeks, interquartile range: 12-14). We investigated the association of maternal vitamin D, corrected for season, with height, leg length and relative leg length at age 5-6 years. Linear regression analyses showed no significant association between maternal vitamin D levels (nmol/l) and height (cm) (B=-0.006; P=0.205), leg length (cm) (B=-0.002, P=0.540) or relative leg length (%) (B=0.001; P=0.579). Adjustment for potential confounders (parental heights, maternal educational level, alcohol use during pregnancy, child sex, child age at measurement and child screen time) did not change these results. Maternal vitamin D level was not associated with early linear growth in children. Other factors, such as parental height, appear to be more important.

Effect of vitamin D administration in vitamin D-deficient pregnant women on maternal and neonatal serum calcium and vitamin D concentrations: a randomised clinical trial

There are several studies in which a correlation between maternal vitamin D deficiency and serum mineral disorders in the mother and the newborn has been reported. The present randomised clinical trial was designed to investigate the effect of vitamin D administration on maternal and fetal Ca and vitamin D status. The trial was carried out on 160 pregnant women. Vitamin D-deficient (25-hydroxyvitamin D (25(OH)D) < 30 ng/ml) pregnant women were recruited at 26-28 weeks of pregnancy. In the control group, a multivitamin supplement containing 400 IU vitamin D3/d was given. Patients in the treatment group were treated with 50 000 IU vitamin D3 weekly for a total duration of 8 weeks. At delivery, maternal and fetal Ca and 25(OH)D levels in both groups were compared. In total, 81 % of pregnant women were vitamin D deficient. At the time of delivery, Ca and vitamin D levels were higher in the treatment group compared with the control group (92 (SD 3) v. 85 (SD 4) mg/l, respectively, P= 0·001 for serum Ca; 47·8 (SD 11·1) v. 15·9 (SD 6·6) ng/ml, respectively, P< 0·001 for vitamin D). At the time of delivery, 32·7 % of women in the control group had hypocalcaemia, while no hypocalcaemic case was detected in the vitamin D-treated group. Mean neonatal serum 25(OH)D was higher in the treatment group compared with the control group (27·7 (SD 5·2) v.10·9 (SD 4·4) ng/ml, respectively, P< 0·01). The neonatal Ca level in the treatment group was significantly higher than that of the control group (99 (SD 3) v. 91 (SD 3) mg/l, respectively, P< 0·001). The administration of vitamin D to pregnant women with vitamin D deficiency improves both maternal and neonatal Ca levels.

Maternal Serum Vitamin D Levels During Pregnancy and Offspring Neurocognitive Development

Maternal Serum Vitamin D Levels During Pregnancy and Offspring Neurocognitive Development

896 Vitamin D Supplementation and the Risk of Infections in Fullterm Infants. Correlations with the Maternal Serum Vitamin D

Vitamin D insufficiency has been linked with susceptibility to infection, autoimmune diseases and cancers.ObjectiveTo study the effect of vitamin D supplementation on the immunity and the risk of infections during...

The Effect of Maternal Vitamin D Concentration on Fetal Bone

Vitamin D deficiency during pregnancy may be associated with suboptimal fetal growth, but direct evidence is lacking. The aim of the study was to validate a method for fetal femur volume (FV) measurement using three-dimensional ultrasound and to detect correlations between FV and maternal vitamin D concentration. A novel method for assessing FV consists of three ultrasound measurements-femur length, proximal metaphyseal diameter (PMD), and midshaft diameter-and a volume equation; this was validated by comparing ultrasound to computed tomography measurements in six pregnancies after mid-trimester termination. This method was then applied in a cohort of healthy pregnant women participating in the Southampton Women Survey. Fetal three-dimensional ultrasound and maternal 25-hydroxyvitamin D [25(OH)D] levels were performed at 34 wk; dual-energy x-ray absorptiometry of the newborn was performed shortly after birth. Univariate and multiple linear regression analyses were performed between maternal characteristics and fetal outcomes. We performed ultrasound measurements of the fetal femur. In 357 pregnant participants, serum 25(OH)D correlated significantly with FV (P = 0.006; r = 0.147) and PMD (P = 0.001; r = 0.176); FV also demonstrated positive univariate correlations with maternal height (P < 0.001; r = 0.246), weight (P = 0.003; r = 0.160), triceps skinfold thickness (P = 0.013; r = 0.134), and a borderline negative effect from smoking (P = 0.061). On multiple regression, independent predictors of FV were the maternal height and triceps skinfold thickness; the effect of 25(OH)D on FV was attenuated, but it remained significant for PMD. Using a novel method for assessing FV, independent predictors of femoral size were maternal height, adiposity, and serum vitamin D. Future trials should establish whether pregnancy supplementation with vitamin D is beneficial for the fetal skeleton, using FV and PMD as fetal outcome measures.

Maternal Early-Pregnancy Vitamin D Status Is Associated With Maternal Depressive Symptoms in the Amsterdam Born Children and Their Development Cohort

To examine low maternal vitamin D status as a potential risk factor for high levels of depressive symptoms in a pregnant population. In the Amsterdam Born Children and Their Development cohort, maternal serum vitamin D (n = 4236) was measured during early pregnancy (median, 13 weeks) and labeled "deficient" (≤ 29.9 nM), "insufficient" (30-49.9 nM), "sufficient" (50-79.9 nM), and "normal" (≥ 80 nM). Maternal depressive symptoms were measured by the Center for Epidemiological Studies Depression Scale at 16-week gestation. The association of vitamin D status with high levels of depressive symptoms (Center for Epidemiological Studies Depression score ≥ 16) was assessed by multivariate logistic regression (final sample, 4101). Overall, 23% of women had vitamin D deficiency, and 21% of women had vitamin D insufficiency. Women with high levels of depressive symptoms (28%) had lower vitamin D concentrations than women with low levels of depressive symptoms (p < .001). After adjustment for constitutional factors, life-style and psychosocial covariates, and sociodemographic factors, vitamin D deficiency (odds ratio [OR], 1.48; 95% confidence interval [CI], 1.13-1.95) and insufficiency (OR, 1.44; 95% CI, 1.12-1.85) were significantly associated with high levels of depressive symptoms. Additional analyses revealed a linear trend, with an OR of 1.05 (95% CI, 1.02-1.08) for each 10-nM decrease in vitamin D status. In this study, low early-pregnancy vitamin D status was associated with elevated depressive symptoms in pregnancy. Further research, using a randomized controlled design, would be required to confirm the causality of this association and the potential benefits of higher vitamin D intake for psychosocial health.

Associations of serum vitamin D concentrations with obstetric glucose metabolism in a subset of the Hyperglycemia and Adverse Pregnancy Outcome (HAPO) study cohort

To assess associations between maternal serum vitamin D concentration and glucose metabolism in a cohort of pregnant women living in an Australian subtropical environment. Cross-sectional assessment of 25-hydroxy vitamin D concentrations in 399 Hyperglycemia and Adverse Pregnancy Outcome ancillary study participants, treated at an obstetric teaching hospital in Brisbane, Australia. All patients underwent a blinded 75-g oral glucose tolerance test at 24-32 (target 28) weeks' gestation. The mean (± standard deviation) fasting plasma glucose was 4.5 ± 0.4 mmol/l. Mean (± standard deviation) serum 25-hydroxy vitamin D was 132.5 ± 44.0 nmol/l. A difference of one standard deviation in maternal 25-hydroxy vitamin D was inversely related to fasting glucose (fasting glucose lower by 0.047 mmol/l, P=0.012) when assessed with multiple linear regression after adjusting for confounders. Maternal 25-hydroxy vitamin D correlated with β-cell function as estimated by the log-transformed homeostasis model assessment-β-cell function equation (r=0.131, P=0.009), but not with the homeostasis model assessment of insulin resistance. An association between mid-gestational 25-hydroxy vitamin D and fasting glucose was confirmed in a largely normoglycaemic and vitamin D-replete pregnant population. The correlation between 25-hydroxy vitamin D and β-cell function suggests that vitamin D may influence glucose metabolism through this mechanism. Intervention studies are required to determine causality and the role of vitamin D replacement in deficient individuals.