Skip to main content

Vitamin D Deficiency in Pregnancy Linked to Low Birth Weight


Vitamin D levels in early pregnancy are closely related to birth weight, head circumference and ponderal index, but not placental growth, in term infants, according to a studypublished online November 16 and in the January 2013 issue of the Journal of Clinical Endocrinology & Metabolism.
Alison D. Gernand, PhD, MPH, a postdoctoral associate in the Department of Epidemiology at the University of Pittsburgh Graduate School of Public Health and School of Medicine in Pennsylvania, and colleagues measured maternal 25-hydroxyvitamin D [25(OH)D] levels to study the relationship between maternal 25(OH)D levels and newborn and placental weight.
Participants were mothers who took part in the Collaborative Perinatal Project, an observational cohort that was conducted in 12 medical centers in the United States from 1959 to 1965.
"Our study is an important contribution to the epidemiology evidence that maternal vitamin D status, especially in early pregnancy, may contribute to both pathological and physiological fetal growth, but not placental growth, in term infants," the authors write.
The mean maternal 25(OH)D was 51.3 ± 28.0 nmol/L. In 34.8% of women, it was less than 37.5 nmol/L, and in 55.9% of women it was less than 50 nmol/L. The incidence of babies who were small for gestational age (SGA) was high.
In a bivariate analysis, women who had 25(OH)D levels of 37.5 nmol/L or more had babies with higher birth weight, head circumference, and ponderal index when compared with those whose 25(OH) levels were less than 37.5 nmol/L, but there were no differences in placental weight and placental-to-fetal weight ratio.
The differences in birth weight and head circumference by vitamin D deficiency remained after adjustment for trimester at maternal blood draw, maternal race/ethnicity, prepregnancy body mass index, height, smoking, season, and study site.
Investigators observed a nonlinear relationship between 25(OH)D levels and birth weight and head circumference ( P < .01).
Birth weight increased by 3.6 g (95% confidence interval [CI], 1.1 - 6.1 g), and head circumference increased by 0.010 cm (95% CI, 0.002 - 0.018 cm) per 1 nmol/L increase in maternal 25(OH)D level up to 37.5 nmol/L, leveling off after that.
The researchers found no relationship between 25(OH)D level and ponderal index, placental weight, or placental-to-fetal weight ratio in adjusted analyses, regardless of the way vitamin D was specified. These associations were unaffected by trimester of vitamin D assessment, maternal race/ethnicity, or infant sex.
The trimester of vitamin D assessment did affect the relationship between maternal 25(OH)D and the risk for SGA ( P < .05).
After adjustment for maternal race/ethnicity, prepregnancy body mass index, height, smoking, season, and study site, maternal 25(OH)D levels of 37.5 nmol/L or greater in the first trimester were associated with almost half the risk for SGA compared with levels less than 37.5 nmol/L.
Each 1 SD increase in 25(OH)D lowered the risk for SGA by 34%. The researchers found no evidence of a nonlinear association, and no relationship existed between second trimester 25(OH)D level and SGA, regardless of the way vitamin D was specified.
"Randomized controlled trials that begin early in pregnancy are needed to provide causal evidence for clinical recommendations regarding vitamin D intake and potential screening in the care of pregnant women," the authors write.
This study was supported by the National Institutes of Health. The authors have disclosed no relevant financial relationships.

Comments

Post a Comment

Popular posts from this blog

Contact Precautions May Have Unintended Consequences

Contact precautions, including gloves, gowns, and isolated rooms, have helped stem the transmission of hospital pathogens but have also had some negative consequences, according to findings from a new study. Healthcare worker (HCWs) visited patients on contact precautions less frequently than other patients and spent less time with those patients when they did visit, report Daniel J. Morgan, MD, from the University of Maryland School of Medicine and the Veterans Affairs (VA) Maryland Health Care System, Baltimore, and colleagues. Moreover, patients on contact precautions also received fewer outside visitors. "Less contact with HCWs suggests that other unintended consequences of contact precautions still exist," Dr. Morgan and coauthors write. "The resulting decrease in HCW contact may lead to increased adverse events and a lower quality of patient care due to less consistent patient monitoring and poorer adherence to standard adverse event prevention methods (such...
Post a Comment
Read more

CareFusion Issues Update on Infant Breathing Product Recall

July 5, 2012 — Medical device maker CareFusion has issued an update reminding healthcare providers of its voluntary recall of its Air Life ™ Infant Breathing Circuit, initiated back in May. The US Food and Drug Administration (FDA) has classified this action as a class 1 recall, meaning there is a reasonable probability of serious adverse health consequences or death associated with use of the defective units. The update was posted July 2 on the FDA  Website. On May 29, 2012, CareFusion sent an  Urgent Recall Notice  to customers and distributors stating that the company had identified potential risks associated with the Air Life  Infant Breathing Circuit. The action was initiated after the company received complaints of the Y adapter within the breathing circuit developing cracks during patient use. "If a crack develops in the Y adapter, this could potentially result in a leak in the closed ventilation system, leading to a loss in the intended tidal volum...
Post a Comment
Read more

Patients With IBS More Likely to Keep Taking Rifaximin

March 29, 2012 — Patients who take the antibiotic rifaximin for irritable bowel syndrome (IBS) with diarrhea are far less likely to stop using the drug because of adverse effects than patients taking 2 other common IBS treatments, according to a study by Eric Shah, MBA, from the School of Medicine at the Texas Tech University Health Sciences Center in Lubbock. The study was published online March 26 and in the April print issue of the American Journal of Medicine . A research team led by Mark Pimentel, MD, from the GI Motility Program at the Cedars-Sinai Medical Center in Los Angeles, California, reviewed 26 clinical trials of drugs for IBS with diarrhea and for IBS with constipation. In forms of IBS with diarrhea, the review found that patients experienced fewer adverse effects from the antibiotic rifaximin than patients who used tricyclic antidepressants or stool-slowing alosetron. For every 2.3 and 2.6 patients who benefited from antidepressants or alosetron, respectively, 1 had...
1 comment
Read more