Paediatric Department, Shahid Sadoughi Medical University, Avicenna St, Yazd, Iran.
Singapore Med J. 2013 May;54(5):285-8. doi: 10.11622/smedj.2013110.
The exact amount of vitamin D required for pregnant women to adequately supply the foetus during pregnancy is still unclear. This randomised 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.
A total of 51 healthy, pregnant women in Yazd, Iran, were recruited in 2009. Of these, 34 were randomised 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.
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.
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.
孕妇在怀孕期间为胎儿提供充足维生素 D 的具体剂量仍不清楚。本随机试验旨在确定怀孕期间维生素 D 的最佳剂量，以确保新生儿血清 25-羟维生素 D（25[OH]D）水平＞20ng/ml。
2009 年，我们在伊朗亚兹德招募了 51 名健康的孕妇。其中 34 名孕妇被随机分为两组，从妊娠中期开始每月分别接受 50,000IU（A 组）或 100,000IU（B 组）维生素 D3。其余 17 名孕妇（C 组）被发现维生素 D 缺乏，首先接受 200,000IU 维生素 D3 治疗，然后调整剂量为每月 50,000IU。采用化学发光免疫分析法测定脐血 25-羟维生素 D（25[OH]D），血清 25（OH）D 水平＜20ng/ml 定义为缺乏。
所有孕妇在妊娠中期开始时维生素 D 水平＜30ng/ml。A 组 76%的孕妇新生儿 25（OH）D 水平充足。B 组和 C 组所有孕妇新生儿 25（OH）D 水平＞20ng/ml。在维生素 D 补充期间，我们的参与者没有观察到不良反应。
对于妊娠中、晚期维生素 D 缺乏的孕妇，每月需要＞50,000IU 维生素 D3 才能使新生儿血清 25（OH）D 水平＞20ng/ml。每月补充＜50,000IU 不足以确保所有维生素 D 缺乏孕妇所生新生儿的 25（OH）D 水平＞20ng/ml。
