Vitamin D Supplementation in Pregnancy and Lactation and Infant Growth


It is unclear whether maternal vitamin D supplementation during pregnancy and lactation improves fetal and infant growth in regions where vitamin D deficiency is common.


We conducted a randomized, double-blind, placebo-controlled trial in Bangladesh to assess the effects of weekly prenatal vitamin D supplementation (from 17 to 24 weeks of gestation until birth) and postpartum vitamin D supplementation on the primary outcome of infants’ length-for-age z scores at 1 year according to World Health Organization (WHO) child growth standards. One group received neither prenatal nor postpartum vitamin D (placebo group). Three groups received prenatal supplementation only, in doses of 4200 IU (prenatal 4200 group), 16,800 IU (prenatal 16,800 group), and 28,000 IU (prenatal 28,000 group). The fifth group received prenatal supplementation as well as 26 weeks of postpartum supplementation in the amount of 28,000 IU (prenatal and postpartum 28,000 group).


Among 1164 infants assessed at 1 year of age (89.5% of 1300 pregnancies), there were no significant differences across groups in the mean (±SD) length-for-age z scores. Scores were as follows: placebo, −0.93±1.05; prenatal 4200, −1.11±1.12; prenatal 16,800, −0.97±0.97; prenatal 28,000, −1.06±1.07; and prenatal and postpartum 28,000, −0.94±1.00 (P=0.23 for a global test of differences across groups). Other anthropometric measures, birth outcomes, and morbidity did not differ significantly across groups. Vitamin D supplementation had expected effects on maternal and infant serum 25-hydroxyvitamin D and calcium concentrations, maternal urinary calcium excretion, and maternal parathyroid hormone concentrations. There were no significant differences in the frequencies of adverse events across groups, with the exception of a higher rate of possible hypercalciuria among the women receiving the highest dose.


In a population with widespread prenatal vitamin D deficiency and fetal and infant growth restriction, maternal vitamin D supplementation from midpregnancy until birth or until 6 months post partum did not improve fetal or infant growth. (Funded by the Bill and Melinda Gates Foundation; number, NCT01924013.)

Infants who are small for gestational age or have impaired postnatal linear growth continue to be of major concern with regard to public health in low- and middle-income countries.1,2 However, environmental and dietary regulation of fetal and infant growth remain inadequately understood. Observational studies have shown numerous early-life risk factors for later anthropometric outcomes,3,4 but there is limited evidence of benefit of prenatal micronutrient interventions on childhood linear growth.5

Vitamin D may influence fetal and postnatal growth through effects on calcium absorption,6parathyroid hormone expression,7 phosphate metabolism,8 growth-plate function,9,10 and regulation of the insulin-like growth factor axis.11 Meta-analyses of observational studies12 and clinical trials13 have suggested that vitamin D may have a beneficial effect on fetal growth, but most previous trials have had methodologic limitations.13 In a previous small trial in Bangladesh, we found that early postnatal linear growth was higher in infants born to women who had received vitamin D supplementation as compared with those who had not received supplementation.14

In Bangladesh, approximately 30% of newborns are small for gestational age,1 and the growth of 36% of children younger than 5 years of age is stunted (height-for-age z score, <−2).15 Vitamin D deficiency is common in Bangladeshi women of reproductive age.16 In the Maternal Vitamin D for Infant Growth (MDIG) trial conducted in Dhaka, Bangladesh, we evaluated the dose-dependent effects of prenatal vitamin D supplementation, with and without postpartum supplementation, on infant growth and other maternal, newborn, and infant outcomes.

Reference: N Engl J Med 2018; 379:535-546


NIHR Signals

The National Institute for Health Research has published new Signals containing summaries of published research for health and social care decision makers:

Continuous glucose monitoring in pregnant women with type 1 diabetes (CONCEPTT)


Pregnant women with type 1 diabetes are a high-risk population who are recommended to strive for optimal glucose control, but neonatal outcomes attributed to maternal hyperglycaemia remain suboptimal. Our aim was to examine the effectiveness of continuous glucose monitoring (CGM) on maternal glucose control and obstetric and neonatal health outcomes.


In this multicentre, open-label, randomised controlled trial, we recruited women aged 18–40 years with type 1 diabetes for a minimum of 12 months who were receiving intensive insulin therapy. Participants were pregnant (≤13 weeks and 6 days’ gestation) or planning pregnancy from 31 hospitals in Canada, England, Scotland, Spain, Italy, Ireland, and the USA. We ran two trials in parallel for pregnant participants and for participants planning pregnancy. In both trials, participants were randomly assigned to either CGM in addition to capillary glucose monitoring or capillary glucose monitoring alone. Randomisation was stratified by insulin delivery (pump or injections) and baseline glycated haemoglobin (HbA1c). The primary outcome was change in HbA1c from randomisation to 34 weeks’ gestation in pregnant women and to 24 weeks or conception in women planning pregnancy, and was assessed in all randomised participants with baseline assessments. Secondary outcomes included obstetric and neonatal health outcomes, assessed with all available data without imputation. This trial is registered with, number NCT01788527.


Between March 25, 2013, and March 22, 2016, we randomly assigned 325 women (215 pregnant, 110 planning pregnancy) to capillary glucose monitoring with CGM (108 pregnant and 53 planning pregnancy) or without (107 pregnant and 57 planning pregnancy). We found a small difference in HbA1c in pregnant women using CGM (mean difference −0·19%; 95% CI −0·34 to −0·03; p=0·0207). Pregnant CGM users spent more time in target (68% vs 61%; p=0·0034) and less time hyperglycaemic (27% vs 32%; p=0·0279) than did pregnant control participants, with comparable severe hypoglycaemia episodes (18 CGM and 21 control) and time spent hypoglycaemic (3% vs 4%; p=0·10). Neonatal health outcomes were significantly improved, with lower incidence of large for gestational age (odds ratio 0·51, 95% CI 0·28 to 0·90; p=0·0210), fewer neonatal intensive care admissions lasting more than 24 h (0·48; 0·26 to 0·86; p=0·0157), fewer incidences of neonatal hypoglycaemia (0·45; 0·22 to 0·89; p=0·0250), and 1-day shorter length of hospital stay (p=0·0091). We found no apparent benefit of CGM in women planning pregnancy. Adverse events occurred in 51 (48%) of CGM participants and 43 (40%) of control participants in the pregnancy trial, and in 12 (27%) of CGM participants and 21 (37%) of control participants in the planning pregnancy trial. Serious adverse events occurred in 13 (6%) participants in the pregnancy trial (eight [7%] CGM, five [5%] control) and in three (3%) participants in the planning pregnancy trial (two [4%] CGM and one [2%] control). The most common adverse events were skin reactions occurring in 49 (48%) of 103 CGM participants and eight (8%) of 104 control participants during pregnancy and in 23 (44%) of 52 CGM participants and five (9%) of 57 control participants in the planning pregnancy trial. The most common serious adverse events were gastrointestinal (nausea and vomiting in four participants during pregnancy and three participants planning pregnancy).


Use of CGM during pregnancy in patients with type 1 diabetes is associated with improved neonatal outcomes, which are likely to be attributed to reduced exposure to maternal hyperglycaemia. CGM should be offered to all pregnant women with type 1 diabetes using intensive insulin therapy. This study is the first to indicate potential for improvements in non-glycaemic health outcomes from CGM use.


Juvenile Diabetes Research Foundation, Canadian Clinical Trials Network, and National Institute for Health Research.

Reference: The Lancet, Volume 390, No. 10110, p2347–2359, 25 November 2017

Antenatal nutritional supplementation and autism spectrum disorders in the Stockholm youth cohort: population based cohort study

Objective To determine whether nutritional supplementation during pregnancy is associated with a reduced risk of autism spectrum disorder (ASD) with and without intellectual disability in offspring.

Design Observational prospective cohort study using multivariable logistic regression, sibling controls, and propensity score matching.

Setting Stockholm County, Sweden.

Participants 273 107 mother-child pairs identified through population registers. The study sample was restricted to children who were aged 4 to 15 years by the end of follow-up on 31 December 2011 and were born between 1996 and 2007.

Exposures Multivitamin, iron, and folic acid supplement use was reported at the first antenatal visit.

Main outcome measure Diagnosis of ASD with and without intellectual disability in children determined from register data up to 31 December 2011.

Results Prevalence of ASD with intellectual disability was 0.26% (158 cases in 61 934) in the maternal multivitamin use group and 0.48% (430 cases in 90 480) in the no nutritional supplementation use group. Maternal multivitamin use with or without additional iron or folic acid, or both was associated with lower odds of ASD with intellectual disability in the child compared with mothers who did not use multivitamins, iron, and folic acid (odds ratio 0.69, 95% confidence interval 0.57 to 0.84). Similar estimates were found in propensity score matched (0.68, 0.54 to 0.86) and sibling control (0.77, 0.52 to 1.15) matched analyses, though the confidence interval for the latter association included 1.0 and was therefore not statistically significant. There was no consistent evidence that either iron or folic acid use were inversely associated with ASD prevalence.

Conclusions Maternal multivitamin supplementation during pregnancy may be inversely associated with ASD with intellectual disability in offspring. Further scrutiny of maternal nutrition and its role in the cause of autism is recommended.

Reference: BMJ 2017;359:j4273

Antidepressant use during pregnancy and psychiatric disorders in offspring: Danish nationwide register based cohort study

Objective To investigate the association between in utero exposure to antidepressants and risk of psychiatric disorders.

Design Population based cohort study.

Setting Danish national registers.

Participants 905 383 liveborn singletons born during 1998-2012 in Denmark and followed from birth until July 2014, death, emigration, or date of first psychiatric diagnosis, whichever came first. The children were followed for a maximum of 16.5 years and contributed 8.1×106 person years at risk.

Exposures for observational studies Children were categorised into four groups according to maternal antidepressant use within two years before and during pregnancy: unexposed, antidepressant discontinuation (use before but not during pregnancy), antidepressant continuation (use both before and during pregnancy), and new user (use only during pregnancy).

Main outcome measure First psychiatric diagnosis in children, defined as first day of inpatient or outpatient treatment for psychiatric disorders. Hazard ratios of psychiatric disorders were estimated using Cox regression models.

Results Overall, psychiatric disorders were diagnosed in 32 400 children. The adjusted 15 year cumulative incidence of psychiatric disorders was 8.0% (95% confidence interval 7.9% to 8.2%) in the unexposed group, 11.5% (10.3% to 12.9%) in the antidepressant discontinuation group, 13.6% (11.3% to 16.3%) in the continuation group, and 14.5% (10.5% to 19.8%) in the new user group. The antidepressant continuation group had an increased risk of psychiatric disorders (hazard ratio 1.27, 1.17 to 1.38), compared with the discontinuation group.

Conclusions In utero exposure to antidepressants was associated with increased risk of psychiatric disorders. The association may be attributable to the severity of underlying maternal disorders in combination with antidepressant exposure in utero. The findings suggest that focusing solely on a single psychiatric disorder among offspring in studies of in utero antidepressant exposure may be too restrictive.

Reference: BMJ 2017;358:j3668

Aspirin versus Placebo in Pregnancies at High Risk for Preterm Preeclampsia


Preterm preeclampsia is an important cause of maternal and perinatal death and complications. It is uncertain whether the intake of low-dose aspirin during pregnancy reduces the risk of preterm preeclampsia.


In this multicenter, double-blind, placebo-controlled trial, we randomly assigned 1776 women with singleton pregnancies who were at high risk for preterm preeclampsia to receive aspirin, at a dose of 150 mg per day, or placebo from 11 to 14 weeks of gestation until 36 weeks of gestation. The primary outcome was delivery with preeclampsia before 37 weeks of gestation. The analysis was performed according to the intention-to-treat principle.


A total of 152 women withdrew consent during the trial, and 4 were lost to follow up, which left 798 participants in the aspirin group and 822 in the placebo group. Preterm preeclampsia occurred in 13 participants (1.6%) in the aspirin group, as compared with 35 (4.3%) in the placebo group (odds ratio in the aspirin group, 0.38; 95% confidence interval, 0.20 to 0.74; P=0.004). Results were materially unchanged in a sensitivity analysis that took into account participants who had withdrawn or were lost to follow-up. Adherence was good, with a reported intake of 85% or more of the required number of tablets in 79.9% of the participants. There were no significant between-group differences in the incidence of neonatal adverse outcomes or other adverse events.


Treatment with low-dose aspirin in women at high risk for preterm preeclampsia resulted in a lower incidence of this diagnosis than placebo. (Funded by the European Union Seventh Framework Program and the Fetal Medicine Foundation; EudraCT number, 2013-003778-29; Current Controlled Trials number, ISRCTN13633058.)

Reference: N Engl J Med 2017; 377:613-622August 17, 2017

Risk of neonatal drug withdrawal after intrauterine co-exposure to opioids and psychotropic medications: cohort study


Objectives To assess the impact of in utero co-exposure to psychotropic medications and opioids on the incidence and severity of neonatal drug withdrawal.

Design Observational cohort study.

Setting Nationwide sample of pregnancies in publicly insured women in the US, nested in the Medicaid Analytic eXtract (2000-10).

Participants 201 275 pregnant women with public insurance who were exposed to opioids around the time of delivery and their liveborn infants.

Interventions In utero exposure to psychotropic medications, in particular antidepressants, atypical antipsychotics, benzodiazepines, gabapentin, and non-benzodiazepine hypnotics (Z drugs), with prescriptions filled within the same time window as prescriptions for opioids.

Main outcome measure Diagnosis of neonatal drug withdrawal in infants exposed in utero to opioids and psychotropic medications compared with opioids alone.

Results The absolute risk for neonatal drug withdrawal ranged from 1.0% in infants exposed in utero to prescription opioids alone to 11.4% for those exposed to opioids co-prescribed with gabapentin. Among neonates exposed in utero to prescription opioids, the relative risk adjusted for propensity score was 1.34 (95% confidence interval 1.22 to 1.47) with concomitant exposure to antidepressants, 1.49 (1.35 to 1.63) with benzodiazepines, 1.61 (1.26 to 2.06) with gabapentin, 1.20 (0.95 to 1.51) with antipsychotics, and 1.01 (0.88 to 1.15) with Z drugs. In utero exposure to two or more psychotropic medications along with opioids was associated with a twofold increased risk of withdrawal (2.05, 1.77 to 2.37). The severity of the withdrawal seemed increased in neonates exposed to both opioids and psychotropic medications compared with opioids alone.

Conclusions During pregnancy, the use of psychotropic medications in addition to prescription opioids is common, despite a lack of safety data. The current findings suggest that these drugs could further increase the risk and severity of neonatal drug withdrawal.

Reference: BMJ 2017;358:j3326