Department of Pediatrics, McMaster University, Hamilton, L8S 4L8, Canada.
Department of Medicine (Cardiology), McMaster University, Hamilton, L8S 4L8, Canada.
Nutrients. 2019 Jan 9;11(1):123. doi: 10.3390/nu11010123.
Vitamin D deficiency in pregnancy is widely reported, but whether this applies in North America is unclear since no population-based surveys of vitamin D status in pregnancy exist in Canada or the United States. The objectives were to assess (i) the intake and sources of vitamin D, (ii) vitamin D status, and (iii) factors associated with serum 25-hydroxyvitamin D (25-OHD) concentration in two cohorts of pregnant women from Southern Ontario, Canada, studied over a span of 14 years. Maternal characteristics, physical measurements, fasting blood samples and nutrient intake were obtained at enrolment in 332 pregnant women from the Family Atherosclerosis Monitoring In early Life (FAMILY) study and 191 from the Be Healthy in Pregnancy (BHIP) study. Serum 25-OHD was measured by LC/MS-MS. The median (Q1, Q3) total vitamin D intake was 383 IU/day (327, 551) in the FAMILY study and 554 IU/day (437, 796) in the BHIP study. Supplemental vitamin D represented 64% of total intake in participants in FAMILY and 78% in BHIP. The mean (SD) serum 25-OHD was 76.5 (32.9) nmol/L in FAMILY and 79.7 (22.3) nmol/L in BHIP. Being of European descent and blood sampling in the summer season were significantly associated with a higher maternal serum 25-OHD concentration. In summary, health care practitioners should be aware that vitamin D status is sufficient in the majority of pregnant Canadian women of European ancestry, likely due to sun exposure.
妊娠期维生素 D 缺乏症的报道较为广泛，但由于加拿大和美国均未进行过针对妊娠期维生素 D 状况的人群调查，因此不清楚这种情况是否适用于北美地区。本研究旨在评估安大略省南部的两个孕妇队列（一项研究为 FAMILY 研究，共纳入 332 名孕妇；另一项研究为 BHIP 研究，共纳入 191 名孕妇）中：（i）维生素 D 的摄入量和来源；（ii）维生素 D 状况；（iii）与血清 25-羟维生素 D（25-OHD）浓度相关的因素。在 FAMILY 研究中，于入组时获取了 332 名孕妇的母体特征、体格测量、空腹血样和营养素摄入量数据；在 BHIP 研究中，于入组时获取了 191 名孕妇的上述数据。采用 LC/MS-MS 法检测血清 25-OHD。FAMILY 研究中，母体总维生素 D 摄入量的中位数（Q1，Q3）为 383IU/天（327，551）；BHIP 研究中，母体总维生素 D 摄入量的中位数（Q1，Q3）为 554IU/天（437，796）。在 FAMILY 研究中，补充维生素 D 占总摄入量的 64%；在 BHIP 研究中，补充维生素 D 占总摄入量的 78%。FAMILY 研究中，母体血清 25-OHD 的平均值（标准差）为 76.5（32.9）nmol/L；BHIP 研究中，母体血清 25-OHD 的平均值（标准差）为 79.7（22.3）nmol/L。与血清 25-OHD 浓度较高相关的因素包括：欧洲裔血统和夏季采血。综上，加拿大的欧洲裔孕妇维生素 D 状态多数情况下较为充足，这可能与日晒有关，因此医疗保健从业者应注意这一点。
