Prevalence of suboptimal vitamin D status during pregnancy. Maternal vitamin D in pregnancy may influence not only offspring bone mass but other aspects of musculoskeletal health and adiposity. Vitamin D and health in pregnancy, infants, children and adolescents in Australia and New Zealand: a position statement. Comparison of sun exposure versus vitamin D supplementation for pregnant women with vitamin D deficiency Vitamin D requirement in pregnancy to prevent deficiency in neonates: a randomised trial. Randomized controlled trial (RCT) of vitamin D supplementation in pregnancy in a population with endemic vitamin D deficiency. Maternal vitamin D supplementation in pregnancy and offspring outcomes: a double-blind randomized placebo-controlled trial Vitamin D requirements during lactation: high-dose maternal supplementation as therapy to prevent hypovitaminosis D for both the mother and the nursing infant. Maternal plasma 25-hydroxyvitamin D concentration and birthweight, growth and bone mineral accretion of Gambian infants Evaluation of Vitamin D Supplementation Doses during Pregnancy in a Population at High Risk for Deficiency Maternal Early-Pregnancy Vitamin D Status Is Associated With Maternal Depressive Symptoms in the Amsterdam Born Children and Their Development Cohort Daily Cholecalciferol Supplementation during Pregnancy Alters Markers of Regulatory Immunity, Inflammation, and Clinical Outcomes in a Randomized Controlled Trial. Vitamin D supplements in pregnant Asian women: effects on calcium status and fetal growth. Vitamin D intake during pregnancy: association with maternal characteristics and infant birth weight. VITAMIN D SUPPLEMENTS ENHANCE WEIGHT GAIN AND NUTRITIONAL STATUS IN PREGNANT ASIANS Determinants of the Maternal 25-Hydroxyvitamin D Response to Vitamin D Supplementation During Pregnancy Maternal Serum and Breast Milk Vitamin D Levels: Findings from the Universiti Sains Malaysia Pregnancy Cohort Study
Low maternal vitamin D status has been associated with reduced intrauterine long bone growth and shorter gestation , decreased birth weight , as well as reduced childhood bone-mineral accrual . Despite data from other countries indicating low maternal vitamin D status is common during pregnancy , there is a dearth of information about vitamin D status during pregnancy in the Irish female population . Therefore , we prospect ively assessed vitamin D nutritive status and the prevalence of suboptimal vitamin D status in a cohort of Irish pregnant women . The mean ( SD ) daily intake of vitamin D  by the group of pregnant women was 3.6 ( 1.9 ) microg/day . None of the women achieved the recommended daily vitamin D intake value for Irish pregnant women ( 10 microg/day ) . Taking all three trimesters collectively , 14.3 - 23.7 % and 34.3 - 52.6 % of Irish women had vitamin D deficiency ( serum 25 ( OH ) D < 25 nmol/l ) and insufficiency ( serum 25 ( OH ) D 25 - 50 nmol/l ) , respectively during pregnancy . Both the levels of serum 25 ( OH ) D and the prevalence of vitamin D deficiency/adequacy were dramatically influenced by season , with status being lowest during the extended winter period and best during the extended summer period . These findings show that inadequate vitamin D status is common in Irish pregnant women Osteoporotic fractures , falls and obesity are major health problems in developed nations . Evidence suggests that there are antenatal factors predisposing to these conditions . Data are emerging from Australia and elsewhere to suggest that maternal vitamin D status in pregnancy affects intrauterine skeletal mineralisation and skeletal growth together with muscle development and adiposity . Given that low levels of vitamin D have been documented in many urbanised population s , including those in countries with abundant sunlight , an important issue for public health is whether maternal vitamin D insufficiency during pregnancy has adverse effects on offspring health . The developing fetus may be exposed to low levels of vitamin D during critical phases of development as a result of maternal hypovitaminosis D. We hypothesise that this may have adverse effects on offspring musculoskeletal health and other aspects of body composition . Further research focused on the implication s of poor gestational vitamin D nutrition is warranted as these developmental effects are likely to have a sustained influence on health during childhood and in adult life . We suggest that there is a clear rationale for r and omised clinical trials to assess the potential benefits and harmful effects of vitamin D supplementation during pregnancy • The recommended level for serum 25-hydroxyvitamin D ( 25(OH)D ) in infants , children , adolescents and during pregnancy and lactation is ≥ 50 nmol/L. This level may need to be 10 - 20 nmol/L higher at the end of summer to maintain levels ≥ 50 nmol/L over winter and spring . • Sunlight is the most important source of vitamin D. The US recommended dietary allowance for vitamin D is 600 IU daily in children aged over 12 months and during pregnancy and lactation , assuming minimal sun exposure . • Risk factors for low vitamin D are : lack of skin exposure to sunlight , dark skin , southerly latitude , conditions affecting vitamin D metabolism and storage ( including obesity ) and , for infants , being born to a mother with low vitamin D and exclusive breastfeeding combined with at least one other risk factor . • Targeted measurement of 25(OH)D levels is recommended for infants , children and adolescents with at least one risk factor for low vitamin D and for pregnant women with at least one risk factor for low vitamin D at the first antenatal visit . • Vitamin D deficiency can be treated with daily low-dose vitamin D supplements , although barriers to adherence have been identified . High-dose intermittent vitamin D can be used in children and adolescents . Treatment should be paired with health education and advice about sensible sun exposure . Infants at risk of low vitamin D should be supplemented with 400 IU vitamin D₃ daily for at least the first year of life . • There is increasing evidence of an association between low vitamin D and a range of non-bone health outcomes , however there is a lack of data from robust r and omised controlled trials of vitamin D supplementation Abstract Introduction : Maternal vitamin D deficiency is widespread health problem that is more important in pregnant women , which affects fetus growth and bone development . The aim of this study was to evaluate the effect of sun exposure versus vitamin D supplementation for pregnant women with vitamin D deficiency . Material s and methods : This prospect i ve clinical trial was performed on 87 pregnant women with vitamin D deficiency . Group A was treated with vitamin D 4000 IU per day for 10 weeks , while group B was recommended for sun exposure for 30 minutes daily ( 30 % body surface area ) for 10 weeks in summer and between 10 am–4 pm in direct sunlight . After the delivery , 25-hydroxyvitamin D3 levels were measured in the same previous center . Moreover , weight , height , and head circumference of fetus were measured at delivery in both groups and compared with each other . Results : After 10-week intervention , 25-hydroxyvitamin D3 levels was significantly higher in group treated with vitamin D as compared to sun expose group ( 31.27 versus 19.79 ng/ml ) . ( p < .001 ) . However , height ( p = .118 ) , weight ( p = .245 ) , and head circumference ( p = .681 ) of infants in both groups did not show significant differences . Conclusions : Vitamin D supplementation is more effective than sun exposure in increasing 25-hydroxyvitamin D3 in pregnant women with vitamin D deficiency INTRODUCTION The exact amount of vitamin D required for pregnant women to adequately supply the foetus during pregnancy is still unclear . This r and omised trial attempted to determine the optimal dose of vitamin D necessary during pregnancy in order to attain a vitamin D level > 20 ng/mL in neonates . METHODS A total of 51 healthy , pregnant women in Yazd , Iran , were recruited in 2009 . Of these , 34 were r and omised to receive either 50,000 IU ( Group A ) or 100,000 IU ( Group B ) of vitamin D3 per month from the second trimester of pregnancy . The remaining 17 pregnant women , who formed the third group ( Group C ) and were found to have vitamin D deficiency , were initially treated with 200,000 IU of vitamin D3 , following which the dose was adjusted to 50,000 IU per month . 25-hydroxyvitamin D ( 25[OH]D ) in cord blood was measured by chemiluminescence immunoassay , and a serum 25(OH)D level < 20 ng/mL was defined as deficiency . RESULTS All the pregnant women had a vitamin D level < 30 ng/mL at the beginning of the second trimester . The neonates of 76 % of women from Group A had sufficient levels of 25(OH)D. All the neonates born to women in Groups B and C had 25(OH)D > 20 ng/mL. No side effects were observed in our participants during the period of vitamin D supplementation . CONCLUSION A vitamin D3dose > 50,000 IU/month is required during the second and third trimesters of pregnancy for vitamin D-deficient pregnant women in order for their neonates to achieve serum 25(OH)D levels > 20 ng/mL. Supplementation with < 50,000 IU/month is insufficient to ensure a vitamin D level > 20 ng/mL in all neonates born to vitamin D-deficient pregnant women BACKGROUND Vitamin D ( vD ) deficiency in pregnancy is a global health problem and the amount of vD supplementation to prevent vD deficiency is controversial . OBJECTIVE The objective of the study was to determine effectiveness and safety of prenatal 2000 IU and 4000 IU/d compared with 400 IU/d vD3 supplementation in a r and omized controlled trial in population in which vD deficiency is endemic . DESIGN / METHODS Arab women were r and omized at 12 - 16 weeks of gestation to 400 , 2000 , and 4000 IU/d  vD3 , which were continued to delivery . Serum 25-hydroxyvitamin D [ 25(OH)D ] concentrations were measured during pregnancy and at delivery . The primary outcome was the maternal and cord blood 25(OH)D , and the secondary outcomes were the achievement of sufficient serum 25(OH)D of 32 ng/mL or greater ( ≥80 nmol/L ) at delivery . SETTING The locations were primary care and tertiary perinatal care centers . RESULTS Of 192 enrolled , 162 ( 84 % ) continued to delivery . Mean serum 25(OH)D of 8.2 ng/mL ( 20.5 nmol/L ) at enrollment was low . Mean serum 25(OH)D concentrations at delivery and in cord blood were significantly higher in the 2000 and 4000 IU than the 400 IU/d group ( P < .001 ) and was highest in the 4000 IU/d group . The percent who achieved 25(OH)D greater than 32 ng/mL and greater than 20 ng/mL concentrations in mothers and infants was highest in 4000 IU/d group . Safety measurements were similar by group and no adverse event related to vD supplementation . CONCLUSIONS Vitamin D supplementation of 2000 and 4000 IU/d appeared safe in pregnancy , and 4000 IU/d was most effective in optimizing serum 25(OH)D concentrations in mothers and their infants . These findings could apply to other population s in which vD deficiency is endemic We studied bone mineral content ( BMC ) , bone mineral density ( BMD ) , and body composition in offspring of women supplemented with vitamin D during pregnancy . Pregnant women were r and omized to receive oral cholecalciferol 60,000 units 4 weekly ( group 1 ) , 8 weekly ( group 2 ) , or placebo ( group 3 ) . All received 1 g calcium daily ( groups 1 and 2 without , and group 3 with 400 units vitamin D ) . Offspring at 12–16 months underwent dual-energy X-ray absorptiometry .  Maternal hypovitaminosis D  at recruitment was common ( serum 25OHD < 50 nmol/L in 88 % ) and severe ( 25OHD < 25 nmol/L in 46 % ) . Groups 1 and 2 ( n = 23 and 13 , median age 14 months ) had higher cord blood 25OHD ( 47.8 ± 13.8 and 31.0 ± 14.0 nmol/L ) versus group 3 ( n = 16 , median age 16 months , 17.8 ± 13.5 nmol/L , p < 0.001 ) . Babies in group 3 had higher whole-body BMC ( 250.8 ± 42.5 gm ) and BMD ( 0.335 ± 0.033 gm/cm2 ) compared to group 1 ( 213.1 ± 46.2 gm and 0.295 ± 0.041 gm/cm2 ) and group 2 ( 202.9 ± 29.9 gm and 0.287 ± 0.023 gm/cm2 ) ( p = 0.006 and 0.001 , respectively ) . In multivariate analysis , age , weight z score , and lean body mass remained significant contributors to BMC . Parameters of body composition were comparable among the groups . Vitamin D supplementation to pregnant women with severe deficiency in doses that improved cord blood 25OHD did not result in improved bone health or body composition in offspring at 12–16 months , compared to a dose too small to improve 25OHD levels Scientific data pertaining to vitamin D supplementation during lactation are scarce . The daily recommended intake for vitamin D during lactation has been arbitrarily set at 400 IU/d ( 10 microg/d ) . This recommendation is irrelevant with respect to maintaining the nutritional vitamin D status of mothers and nursing infants , especially among darkly pigmented individuals . Our objective was to examine the effect of high-dose maternal vitamin D2 supplementation on the nutritional vitamin D status  of mothers and nursing infants . Fully lactating women ( n = 18 ) were enrolled at 1 mo after birth to 1 of 2 treatment arms , ie , 1600 IU vitamin D2 and 400 IU vitamin D3 ( prenatal vitamin ) or 3600 IU vitamin D2 and 400 IU vitamin D3 , for a 3-mo study period . High-dose ( 1600 or 3600 IU/d ) vitamin D2 supplementation for a period of 3 mo safely increased circulating 25-hydroxyvitamin D [ 25(OH)D ] concentrations for both groups . The antirachitic activity of milk from mothers receiving 2000 IU/d vitamin D increased by 34.2 IU/L , on average , whereas the activity in the 4000 IU/d group increased by 94.2 IU/L. Nursing infant circulating 25(OH)D2 concentrations reflected maternal intake and the amount contained in the milk . With limited sun exposure , an intake of 400 IU/d vitamin D would not sustain circulating 25(OH)D concentrations and thus would supply only limited amounts of vitamin D to nursing infants in breast milk . A maternal intake of 2000 IU/d vitamin D would elevate circulating 25(OH)D concentrations for both mothers and nursing infants , albeit with limited capacity , especially with respect to nursing infants . A maternal intake of 4000 IU/d could achieve substantial progress toward improving both maternal and neonatal nutritional vitamin D status Maternal vitamin D deficiency during pregnancy is a recognized risk factor for rickets and osteomalacia in infancy ( 1 ) . The circulating plasma concentration of 25-hydroxyvitamin D ( 25OHD ) , a long-lived metabolite of vitamin D , is used to judge vitamin D status ; values below 25 nmol/L are associated with an increased risk of rickets and osteomalacia ( 1 ) . There is evidence that a low maternal plasma 25OHD in pregnancy may influence the growth and bone mineral accrual of the offspring during foetal life , infancy and childhood . Positive associations have been reported between maternal  vitamin D  status in pregnancy and birthweight , birth length , length at 1 year and bone mineral accretion at 9 years ( 2–6 ) , although evidence is conflicting ( 7,8 ) . These relationships have been observed at concentrations of 25OHD higher than those associated with rickets and osteomalacia , and there are calls to raise the accepted lower threshold of vitamin D sufficiency for pregnant women , most recently to 80 nmol/L ( 9 ) . On a population basis , plasma 25OHD concentrations above 80 nmol/L are relatively uncommon in countries at temperate latitudes but are more common among people living in the tropics who have abundant skin sunshine exposure ( 10 ) . To contribute to the debate on the definition of vitamin D sufficiency in pregnancy , we have investigated the influence of maternal plasma 25OHD concentration on foetal and infant growth in a rural area of The Gambia , West Africa ( 13 ° N ) . In this region , there is tropical sunshine all year , the women are farmers who work out-of-doors for much of each day , and local female dress does not restrict regular sunshine exposure to the face , neck , shoulders , arms and feet , especially during farm work and gardening . The study was a secondary analysis of biochemical , anthropometric and bone data from a subset of 125 women and infants collected during a calcium supplementation study of blood pressure in pregnant Gambian women ( International Trial Registry : IS RCT N96502494 ) . No significant benefits for foetal and infant growth of maternal calcium supplementation were identified despite the low customary calcium intake in The Gambia ( 11 ) . The protocol , methods , maternal characteristics and infant data from the detailed study have been published ( 11 ) . Briefly , women from the rural villages of Keneba and M and uar , West Kiang , The Gambia were recruited at 20 weeks of pregnancy ( P20 ) and r and omized to a daily calcium supplement or a matching placebo tablet until parturition ( 1500 mg Ca as calcium carbonate and microcellulose-lactose , respectively ; Nycomed Pharma AS , Asker , Norway ) . Fasting , early morning blood was collected and anthropometry performed at P20 and 36 weeks of pregnancy ( P36 ) . The mean ( ± SD ) age , weight , height and dietary calcium intake of the women at P20 were 27.4 ± 7.5 years , 56.3 ± 6.7 kg , 1.61 ± 0.05 m and 356 ± 190 mg/day , respectively . The median parity ( range ) was 3 ( 0–10 ) . Infant birthweight was measured within 24 h of delivery . Weight , crown-heel length and head circumference were measured at 2 , 13 and 52 weeks postpartum . In addition , infant bone mineral content ( BMC ) , bone mineral density ( BMD ) and bone width ( BW ) or bone area ( BA ) , were measured by single photon absorptiometry of the midshaft radius ( Lunar SP2 , Lunar Corporation , Madison , WI , USA ) and , for a subset ( n = 44 , 47 and 52 at 2 , 13 and 52 weeks , respectively ) , by whole-body dual-energy X-ray absorptiometry ( Lunar DPX+ , software version 4.7b , Lunar Corporation ) . Plasma 25OHD was measured a using radioimmunometric assay ( Diasorin Ltd , Wokingham , Berks , UK ) , with assay performance monitored through the Vitamin D External Quality Assessment Scheme ( DEQAS ; Endocrine/Oncology Laboratory , Charing Cross Hospital , London , UK ) . The intra- and inter-assay coefficients of variation were 4 % and 100 ) ; possible trends in the data with p = 0.01–0.1 were noted . The analysis was conducted on 123 mother – infant pairs ; blood sample s from two subjects were not available . Mean ± SD 25OHD ( range ) was : P20 = 103 ± 25 ( 53–167 ) nmol/L ; P36 = 111 ± 27 ( 51–189 ) nmol/L. No subject had a 25OHD value < 50 nmol/L , 20 % and 16 % had 25OHD < 80 nmol/L , at P20 and P36 , respectively . There was a high degree of within-subject consistency in 25OHD at P20 and P36 ( 25OHDP36 = 33.2 + [ 0.79 ± 0.07] × 25OHDP20 , p ≤ 0.001 , R2 adjusted 51.5 % , n = 121 ) ; 11 % of women had 25OHD < 80 nmol/L at both P20 and P36 . The mean birthweight of the infants was 2.99 ± 0.36 kg . The infant anthropometric and bone measures during the first year are given in Table 1 . No significant relationships or trends in the data were observed between maternal 25OHD concentration using the values at P20 , P36 or the mean of the two and any of the following infant measures : birthweight , infant weight , length , head circumference , BMC , BW ( or BA ) , BMD and size-adjusted BMC of the midshaft radius and whole body at any time postpartum . This is illustrated in Figure 1 for birthweight as a function of maternal 25OHD concentration at P20 . Comparing the results for mothers with 25OHD above and below 80 nmol/L did not alter this finding . Table 1 Anthropometric and bone measures  of Gambian infants Figure 1 Lack of a significant relationship between infant birthweight and maternal vitamin D status at 20 weeks of pregnancy ( p = 0.8 ) . Multiple regression model included season , maternal height , weight , weight gain , supplement group and sex of the infant . No significant interaction between supplement group and maternal 25OHD concentration was observed for any infant variable . Trends in the data were observed in a few instances for a supplement group × 25OHD interaction among the bone measures but no consistent picture emerged and they were considered to have arisen by chance . We conclude that there is no evidence for an influence of vitamin D status during pregnancy on infant growth and bone mineral accrual in the conditions prevailing in The Gambia . The children in this study , as is common in this region of The Gambia ( 13 ) , were born small , grew well for the first months of life but experienced growth faltering during later infancy compared to Western children ( 11,14 ) , as demonstrated by their weight and length SDS . The 25OHD concentrations of the women were > 50 nmol/L in the second half of pregnancy , and no distinction could be drawn in infant outcomes between mothers with concentrations above or below 80 nmol/L. Thus , our study suggests that , for women with regular , adventitious UVB sunshine exposure and in situations where foetal and infant growth may be constrained by multiple factors , there would be no benefit for foetal and infant growth or bone mineral accrual in aim ing to increase the vitamin D status of individual mothers during pregnancy above 50 or 80 Aim / Background : Vitamin D supplementation during pregnancy is a well-accepted recommendation worldwide ; however , the debate about the correct dose is ongoing . We aim ed to compare daily doses of 600 , 1,200 , and 2,000 IU in this r and omized , controlled study . Methods : The study group consisted of 91 pregnant women aged 16 - 42 years admitted to Kocaeli Maternity and Children Hospital between April 2011 and April 2012 . The participants were r and omly divided into 3 groups . 600 , 1,200 , and 2,000 IU/day of vitamin D was supplemented to group 1 ( control group , n = 31 ) , group 2 ( n = 31 ) , and group 3 ( n = 32 ) , respectively . Serum calcium , 25-hydroxyvitamin D ( 25OHD ) , and the calcium/creatinine ratio in spot urine sample s were measured in the follow-up period . The serum calcium and 25OHD levels of the mothers ' infants were measured as well . Results : The frequency of vitamin D sufficiency after supplementation was 80 % in group 3 and it was significantly higher than in groups 1 ( 42 % ) and 2 ( 39 % ) ( p = 0.03 ) . The frequency of vitamin D sufficiency in the infants of the participants was 91 % in group 3 and it was significantly higher than in groups 1 ( 36 % ) and 2 ( 52 % ) ( p = 0.006 ) . Conclusions : At least 2,000 IU/day of vitamin D is needed to ensure adequate vitamin D status in pregnancy and early infancy Objective To examine low maternal vitamin D  status as a potential risk factor for high levels of depressive symptoms in a pregnant population . Methods 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 ) . Results 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 . Conclusions In this study , low early-pregnancy vitamin D status was associated with elevated depressive symptoms in pregnancy . Further research , using a r and omized controlled design , would be required to confirm the causality of this association and the potential benefits of higher vitamin D intake for psychosocial health BACKGROUND Vitamin D deficiency is widespread in pregnancy and has been associated with adverse health conditions in mothers and infants .  Vitamin D supplementation in pregnancy may support the maintenance of pregnancy by its effects on innate and adaptive immunity . OBJECTIVE We assessed the effects of vitamin D supplementation during pregnancy on vitamin D status and markers of immune function associated with adverse pregnancy outcomes . METHODS We conducted a r and omized , controlled , double-blind intervention of 2 doses of cholecalciferol ( 400 and 2000 IU/d ) from < 20 wk to delivery in 57 pregnant women .  Vitamin D status , regulatory and inflammatory T cells , markers of innate immunity and systemic inflammation , and clinical outcomes including maternal blood pressure and birth weight were assessed at 26 and 36 wk of pregnancy . RESULTS Supplementation with 2000 IU/d vitamin D had a greater effect on the change in vitamin D status over pregnancy ( P < 0.0001 ) and the final value at 36 wk ( P < 0.0001 ) than 400 IU/d , increasing serum 25-hydroxyvitamin D from 81.1 nmol/L at baseline to 116 nmol/L at 36 wk and from 69.6 nmol/L at baseline to 85.6 nmol/L at 36 wk , respectively . The 2000-IU/d group had 36 % more interleukin-10 + regulatory CD4 + T cells at 36 wk than did the 400-IU/d group ( P < 0.007 ) . The daily intake of 2000 compared with 400 IU/d tended to dampen the pregnancy-related increase in diastolic blood pressure by 1.3-fold ( P = 0.06 ) and increase birth weight by 8.6 % ( P = 0.06 ) , but these differences were not statistically significant . CONCLUSIONS Supplementation with 2000 IU/d is more effective at increasing vitamin D status in pregnant women than 400 IU/d and is associated with increased regulatory T cell immunity that may prevent adverse outcomes caused by excess inflammation . This trial was registered at clinical trials.gov as NCT01417351 In a double-blind trial of vitamin D supplements in pregnant Asian women calciferol ( ergocalciferol , 1000 IU/day ) was administered to 59 women and placebo to 67 controls during the last trimester . The two groups had similar distributions of maternal age , height , parity , number of vegetarians , countries of origin , and sex and gestation of the infants . At entry to the trial maternal serum 25-hydroxy vitamin D ( 25-OHD ) concentrations were low in both treatment and control groups and significantly lower in vegetarians than non-vegetarians . Mothers in the treatment group gained weight faster in the last trimester than those in the control group , and at term they and their infants all had adequate plasma 25-OHD concentrations , Mothers and infants in the control group , however , had low plasma concentrations of 25-OHD and calcium and raised plasma alkaline phosphatase ( bone isoenzyme ) activity . Five of these infants developed symptomatic hypocalcaemia . Almost twice as many infants in the control group were small for gestational age ( 29 % v 15 % ) , but there were no significant differences between the two groups of infants in antropometric measurements . Infants in the control group , however , had larger fontanelles , suggesting impaired ossification of the skull . Because of the benefits to mothers and infants in the treatment group and the absence of side effects , vitamin D supplements should be given to all pregnant Asian women in the United Kingdom BACKGROUND Vitamin D insufficiency is beginning to be recognized as a public health problem . It is plausible that some portion of the lower Vitamin D levels which characterize minority population s is related to diet . AIMS We examined and described total Vitamin D intake during pregnancy from the mean of three 24-hour recalls plus use of dietary supplements . STUDY DESIGN Prospect i ve cohort . SUBJECTS 2251 low income , minority gravidae from Camden , New Jersey , USA . OUTCOME MEASURES Differences in total Vitamin D intake by maternal ethnicity . BMI and other factors ( age , parity ) and associations of total Vitamin D intake with gestation duration and birth weight adjusted for gestation . RESULTS AND CONCLUSIONS Total Vitamin D intake was significantly lower for minority gravidae ( African American , and Hispanic , mainly Puerto Rican ) , for parous women , and for women with pregravid BMI s consistent with obesity or being overweight . After control for energy , other nutrients , and other potential confounding variables , total intake of Vitamin D was associated with increased infant birth weight ; gravidae below the current adequate intake ( < 5 microg/day or 200 IU ) had infants with significantly lower birth weights ( p<0.05 ) . Additional intake of Vitamin D may be of importance since higher intake is associated with increased birth weight in a population at risk of adverse pregnancy outcomes In a double blind trial of supplementary vitamin D ( 1000 iu daily ) administered in the last trimester of pregnancy to Asian women living in London , supplemented mothers gained weight faster ( 63.3 g/day ) than those in the control group ( 46.4 g/day ) , and at term had significantly higher plasma levels of retinol binding protein and thyroid binding prealbumin indicating better protein‐calorie nutrition . Maternal weight gain correlated with postpartum levels of both retinol binding protein and thyroid binding prealbumin . Almost twice as many infants in the unsupplemented group weighed under 2500 g at birth , and had significantly lower retinol binding protein levels than infants of supplemented mothers . The nutritional benefits of supplementation provide further support for the routine administration of vitamin D to all British Asians during pregnancy Context : Current approaches to antenatal vitamin D supplementation do not account for interindividual differences in 25-hydroxyvitamin D ( 25(OH)D ) response . Objective : We assessed which maternal and environmental characteristics were associated with 25(OH)D after supplementation with cholecalciferol . Design : Within-r and omization-group analysis of participants in the Maternal Vitamin D Osteoporosis Study trial of vitamin D  supplementation in pregnancy . Setting : Hospital antenatal clinics . Participants : A total of 829 pregnant women ( 422 placebo , 407 cholecalciferol ) . At 14 and 34 weeks of gestation , maternal anthropometry , health , and lifestyle were assessed and 25(OH)D measured . Compliance was determined using pill counts at 19 and 34 weeks . Interventions : 1000 IU/d of cholecalciferol or matched placebo from 14 weeks of gestation until delivery . Main Outcome Measure : 25(OH)D at 34 weeks , measured in a single batch ( Diasorin Liaison ) . Results : 25(OH)D at 34 weeks of gestation was higher in the women r and omized to vitamin D ( mean [ SD ] , 67.7 [ 21.3 ] nmol/L ) compared with placebo ( 43.1 [ 22.5 ] nmol/L ; P < .001 ) . In women r and omized to cholecalciferol , higher pregnancy weight gain from 14 to 34 weeks of gestation ( kg ) ( β = −0.81 [ 95 % confidence interval −1.39 , −0.22 ] ) , lower compliance with study medication ( % ) ( β = −0.28 [ −0.072 , −0.48 ] ) , lower early pregnancy 25(OH)D ( nmol/L ) ( β = 0.28 [ 0.16 , 0.40 ] ) , and delivery in the winter vs the summer ( β = −10.5 [ −6.4 , −14.6 ] ) were independently associated with lower 25(OH)D at 34 weeks of gestation . Conclusions : Women who gained more weight during pregnancy had lower 25(OH)D in early pregnancy and delivered in winter achieved a lower 25(OH)D in late pregnancy when supplemented with 1000 IU/d cholecalciferol . Future studies should aim to determine appropriate doses to enable consistent repletion of 25(OH)D during pregnancy Background Vitamin D deficiency has become a global health issue in pregnant women . This study aim ed to assess the adequacy of maternal vitamin D status by measuring maternal serum and breast milk 25-hydroxyvitamin D [ 25(OH)D ] levels and to determine the association between maternal serum and milk 25(OH)D levels . Methods Data was obtained from the Universiti Sains Malaysia Pregnancy Cohort Study . This study was conducted from April 2010 to December 2012 in the state of Kelantan , Malaysia . Blood sample s from pregnant women aged 19 to 40 years were drawn in the second and third trimesters of pregnancy , while breast milk sample s at delivery , 2 , 6 and 12 months postpartum were collected to analyze for 25(OH)D levels . A total of 102 pregnant women were included in the analysis . Results Vitamin D deficiency [ 25(OH)D < 50 nmol/L ] was detected in 60 % and 37 % of women in the second and third trimesters of pregnancy , respectively . There were 6 % and 23 % of women who reached normal level of vitamin D status in the second trimester and the third trimester , respectively . Multivitamin intakes during pregnancy were significantly associated with higher serum 25(OH)D levels in the second trimester ( β = 9.16 , p = 0.005 ) and the third trimester ( β = 13.65 , p = 0.003 ) . 25(OH)D levels in breast milk during the first year of lactation ranged from 1.01 to 1.26 nmol/L. Higher maternal serum 25(OH)D level in the second trimester of pregnancy was associated with an elevated level of 25(OH)D in breast milk at delivery ( β = 0.002 , p = 0.026 ) . Conclusions This study shows that high proportions of Malay pregnant women are at risk of vitamin D deficiency . Maternal vitamin D status in the second trimester of pregnancy was found to influence vitamin D level in breast milk at delivery
Meta-analyses of r and omized controlled trials ( RCTs ) document that physiological vitamin D supplementation during pregnancy is safe and improves vitamin D and calcium status , thereby protecting skeletal health .
Although certain RCTs and /or meta-analyses reported some other beneficial effects , it is still not clear whether vitamin D supplementation  improves fertility or decreases the risk of adverse pregnancy outcomes such as low birth weight , pre-eclampsia and neonatal mortality , or reduces wheeze/asthma in the infants .
Vitamin D deficiency is common and there exists a huge gap between recommended dietary vitamin D intakes and the poor vitamin D supply in the general population .
While vitamin D is important for musculoskeletal health , there are accumulating data suggesting that vitamin D may also be important for fertility , pregnancy outcomes and lactation .
Significant changes in vitamin D metabolism during pregnancy such as increased production of the " active vitamin D hormone " calcitriol support the important role of vitamin D in this setting .
Observational studies show that vitamin D deficiency is a risk marker for reduced fertility and various adverse pregnancy outcomes and is associated with a low vitamin D content of breast milk .
Nevertheless , vitamin D supplementation in pregnant women is frequently required to achieve a sufficient vitamin D status as recommended by nutritional vitamin D guidelines .