EA Martin Program in Human Nutrition, SWC, Box 506, South Dakota State University, Brookings, SD 57007, USA.
Proc Nutr Soc. 2012 Feb;71(1):38-45. doi: 10.1017/S0029665111003053. Epub 2011 Aug 24.
During pregnancy, maternal and fetal Ca demands are met through increased intestinal Ca absorption. Increased Ca absorption may be more dependent on oestrogen's up-regulation of Ca transport genes than on vitamin D status. Numerous studies, however, have found that severe vitamin D deficiency with secondary hyperparathyroidism during pregnancy leads to abnormal Ca homoeostasis in the neonate. Some, but not all, studies of maternal vitamin D supplementation during pregnancy find a greater birth weight among infants of mothers with adequate vitamin D status. Observational studies find a higher incidence of small-for-gestational age (SGA) infants among mothers who are vitamin D deficient, but this effect may be modified by genetics. In addition, the effect of vitamin D status on SGA may not be linear, with increased occurrence of SGA at high maternal 25-hydroxyvitamin D (25-OHD) concentrations. Some studies, but not all, also have found that maternal vitamin D status is associated with growth trajectory during the first year of life, although the findings are contradictory. There are recent studies that suggest maternal 25-OHD, or surrogates of vitamin D status, are associated with growth and bone mass later in childhood. These results are not consistent, and blinded randomised trials of vitamin D supplementation during pregnancy with long-term follow-up are needed to determine the benefits, and possible risks, of maternal vitamin D status on offspring growth and bone development. The possibility of adverse outcomes with higher maternal 25-OHD concentrations should be considered and investigated in all ongoing and future studies.
在妊娠期间，母体和胎儿的钙需求通过增加肠道钙吸收来满足。钙吸收的增加可能更依赖于雌激素对钙转运基因的上调，而不是维生素 D 状态。然而，许多研究发现，妊娠期间严重的维生素 D 缺乏伴继发性甲状旁腺功能亢进会导致新生儿钙稳态异常。一些（但不是全部）关于妊娠期间母体维生素 D 补充的研究发现，维生素 D 状态充足的母亲所生婴儿的出生体重更大。观察性研究发现，维生素 D 缺乏的母亲所生的小于胎龄儿（SGA）的发生率较高，但这种影响可能受到遗传因素的影响。此外，维生素 D 状态对 SGA 的影响可能不是线性的，高母体 25-羟维生素 D（25-OHD）浓度会增加 SGA 的发生。一些研究（但不是全部）还发现，母体维生素 D 状态与生命第一年的生长轨迹有关，尽管结果存在矛盾。最近的一些研究表明，母体 25-OHD 或维生素 D 状态的替代物与儿童后期的生长和骨量有关。这些结果并不一致，需要进行随机对照试验，在妊娠期间补充维生素 D 并进行长期随访，以确定母体维生素 D 状态对后代生长和骨骼发育的益处和可能的风险。应考虑并研究所有正在进行和未来的研究中较高的母体 25-OHD 浓度可能带来的不良后果。
