Open AccessA Nested Case-Control Study of First-Trimester Maternal Vitamin D Status and Risk for Spontaneous Preterm Birth
Author(s) -
Arthur Baker,
Sina Haeri,
Carlos A. Camargo,
Alison M. Stuebe,
Kim Boggess
Publication year - 2011
Publication title -
american journal of perinatology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.793
H-Index - 67
eISSN - 1098-8785
pISSN - 0735-1631
DOI - 10.1055/s-0031-1276731
Subject(s) - medicine , interquartile range , nested case control study , obstetrics , vitamin d and neurology , cohort , vitamin d deficiency , pregnancy , cohort study , case control study , premature birth , gestation , gynecology , biology , genetics
We assessed if first-trimester vitamin D deficiency is more prevalent in women who experienced a spontaneous preterm birth compared with women who delivered at term. We conducted a nested case-control study of pregnant women who had previously given blood for first-trimester combined screening for trisomy 21 and subsequently delivered at a tertiary hospital between November 2004 and July 2009. From an overall cohort of 4225 women, 40 cases of spontaneous preterm birth (≥ 23 (0/7) and ≤ 34 (6/7) weeks) were matched by race/ethnicity with 120 women delivering at term (≥ 37 (0/7) weeks) with uncomplicated pregnancies. Banked maternal serum was used to measure maternal 25-hydroxyvitamin D [25(OH)D]. The prevalence of first-trimester maternal vitamin D deficiency [25(OH)D < 50 nmol/L] was comparable among women who subsequently delivered preterm compared with controls (7.5% versus 6.7%, P = 0.90). The median 25(OH)D level for all subjects was 89 nmol/L (interquartile range, 73 to 106 nmol/L). Seventy-three percent (117/160) of the cohort had sufficient vitamin D levels [25(OH)D ≥ 75 nmol/L]. In a cohort of pregnant women with mostly sufficient levels of first-trimester serum 25(OH)D, vitamin D deficiency was not associated with spontaneous preterm birth.