TY - JOUR
T1 - Estimation of the maternal vitamin D intake that maintains circulating 25-hydroxyvitamin D in late gestation at a concentration sufficient to keep umbilical cord sera ≥25-30 nmol/L
T2 - A dose-response, double-blind, randomized placebo-controlled trial in pregnant women at northern latitude
AU - O'Callaghan, Karen M
AU - Hennessy, Áine
AU - Hull, George L J
AU - Healy, Karina
AU - Ritz, Christian
AU - Kenny, Louise C
AU - Cashman, Kevin D
AU - Kiely, Mairead E
N1 - CURIS 2018 NEXS 197
PY - 2018/7/1
Y1 - 2018/7/1
N2 - Background In the absence of dose-response data, Dietary Reference Values for vitamin D in nonpregnant adults are extended to pregnancy. Objective The aim was to estimate vitamin D intake needed to maintain maternal 25-hydroxyvitamin D [25(OH)D] in late gestation at a concentration sufficient to prevent newborn 25(OH)D <25-30 nmol/L, a threshold indicative of increased risk of nutritional rickets. Design We conducted a 3-arm, dose-response, double-blind, randomized placebo-controlled trial in Cork, Ireland (51.9 o N). A total of 144 white-skinned pregnant women were assigned to receive 0, 10 (400 IU), or 20 (800 IU) μg vitamin D 3 /d from ≤18 wk of gestation. Vitamin D metabolites at 14, 24, and 36 wk of gestation and in cord sera, including 25(OH)D 3, 3-epi-25(OH)D 3, 24,25(OH) 2 D 3, and 25(OH)D 2 were quantified by liquid chromatography-tandem mass spectrometry. A curvilinear regression model predicted the total vitamin D intake (from diet and antenatal supplements plus treatment dose) that maintained maternal 25(OH)D in late gestation at a concentration sufficient to maintain cord 25(OH)D at ≥25-30 nmol/L. Results Mean ± SD baseline 25(OH)D was 54.9 ± 10.7 nmol/L. Total vitamin D intakes at the study endpoint (36 wk of gestation) were 12.1 ± 8.0, 21.9 ± 5.3, and 33.7 ± 5.1 μg/d in the placebo and 10-μg and 20-μg vitamin D 3 groups, respectively; and 25(OH)D was 24.3 ± 5.8 and 29.2 ± 5.6 nmol/L higher in the 10- and 20-μg groups, respectively, compared with placebo (P < 0.001). For maternal 25(OH)D concentrations ≥50 nmol/L, 95% of cord sera were ≥30 nmol/L and 99% were >25 nmol/L. The estimated vitamin D intake required to maintain serum 25(OH)D at ≥50 nmol/L in 97.5% of women was 28.9 μg/d. Conclusions Thirty micrograms of vitamin D per day safely maintained serum 25(OH)D concentrations at ≥50 nmol/L in almost all white-skinned women during pregnancy at a northern latitude, which kept 25(OH)D at >25 nmol/L in 99% and ≥30 nmol/L in 95% of umbilical cord sera. This trial was registered at www.clinicaltrials.gov as NCT02506439.
AB - Background In the absence of dose-response data, Dietary Reference Values for vitamin D in nonpregnant adults are extended to pregnancy. Objective The aim was to estimate vitamin D intake needed to maintain maternal 25-hydroxyvitamin D [25(OH)D] in late gestation at a concentration sufficient to prevent newborn 25(OH)D <25-30 nmol/L, a threshold indicative of increased risk of nutritional rickets. Design We conducted a 3-arm, dose-response, double-blind, randomized placebo-controlled trial in Cork, Ireland (51.9 o N). A total of 144 white-skinned pregnant women were assigned to receive 0, 10 (400 IU), or 20 (800 IU) μg vitamin D 3 /d from ≤18 wk of gestation. Vitamin D metabolites at 14, 24, and 36 wk of gestation and in cord sera, including 25(OH)D 3, 3-epi-25(OH)D 3, 24,25(OH) 2 D 3, and 25(OH)D 2 were quantified by liquid chromatography-tandem mass spectrometry. A curvilinear regression model predicted the total vitamin D intake (from diet and antenatal supplements plus treatment dose) that maintained maternal 25(OH)D in late gestation at a concentration sufficient to maintain cord 25(OH)D at ≥25-30 nmol/L. Results Mean ± SD baseline 25(OH)D was 54.9 ± 10.7 nmol/L. Total vitamin D intakes at the study endpoint (36 wk of gestation) were 12.1 ± 8.0, 21.9 ± 5.3, and 33.7 ± 5.1 μg/d in the placebo and 10-μg and 20-μg vitamin D 3 groups, respectively; and 25(OH)D was 24.3 ± 5.8 and 29.2 ± 5.6 nmol/L higher in the 10- and 20-μg groups, respectively, compared with placebo (P < 0.001). For maternal 25(OH)D concentrations ≥50 nmol/L, 95% of cord sera were ≥30 nmol/L and 99% were >25 nmol/L. The estimated vitamin D intake required to maintain serum 25(OH)D at ≥50 nmol/L in 97.5% of women was 28.9 μg/d. Conclusions Thirty micrograms of vitamin D per day safely maintained serum 25(OH)D concentrations at ≥50 nmol/L in almost all white-skinned women during pregnancy at a northern latitude, which kept 25(OH)D at >25 nmol/L in 99% and ≥30 nmol/L in 95% of umbilical cord sera. This trial was registered at www.clinicaltrials.gov as NCT02506439.
KW - Faculty of Science
KW - 25-hydroxyvitamin D
KW - Dietary requirements
KW - Dose-response
KW - ODIN
KW - Neonatal
KW - Pregnancy
KW - Randomized controlled trial
KW - Vitamin D
KW - Vitamin D requirements
U2 - 10.1093/ajcn/nqy064
DO - 10.1093/ajcn/nqy064
M3 - Journal article
C2 - 29878035
SN - 0002-9165
VL - 108
SP - 77
EP - 91
JO - American Journal of Clinical Nutrition
JF - American Journal of Clinical Nutrition
IS - 1
ER -