妊娠早期妇女维生素D营养状况调查

Vitamin D status in early pregancy

目的了解妊娠早期妇女25-羟基维生素D25-(OH)-D的水平及相关因素。方法采用化学发光微粒子免疫法检测23396例妊娠早期(孕龄≤90d)孕妇血清中25-(OH)-D水平及其在不同年龄、不同体质量指数(BMI)、不同季节、初产妇和经产妇的水平分布及差异,同时以早产为临床结局的观察指标。结果23396例妊娠早期孕妇25-(OH)-D平均为42.0(17.6~76.6)nmol/L,5th和95th的25-(OH)-D分别为20.2nmol/L和70.7nmol/L;初产妇18170(77.7%)例,经产妇5226(22.3%)例,孕妇年龄平均30.0(24.0~38.0)岁,BMI20.7(16.5~27.6)kg/m^2,春(3、4、5月)、夏(6、7、8月)、秋(9、10、11月)、冬(12、1、2)检测的例数分别为5878、5554、5974、5990例,25-(OH)-D分别为40.0(29.3,52.7)、46.2(35.6,57.2)、43.8(33.1,54.8)、37.2(26.9,49.9)nmol/L,差异有统计学意义(P<0.001);按BMI划分为BMI<18.5kg/m^2,18.5kg/m^2≤BMI≤23.9kg/m^2,24kg/m^2≤BMI≤27.9kg/m^2,BMI≥28kg/m^24组,25-(OH)-D分别为43.5(30.9,56.9)、42.1(30.8,53.8)、39.9(30.7,50.4)、39.7(30.7,49.4)nmol/L,差异有统计学意义(P<0.001);各年龄组人群<25岁,25~29岁,30~34岁,≥35岁,25-(OH)-D分别为39.1(28.4,52.3)、41.3(30.1,52.9)、42.4(31.2,54.1)、43.8(31.9,55.7)nmol/L,各年龄组之间的差异有统计学意义(P<0.001);初产妇和经产妇25-(OH)-D分别为41.6(30.2,52.9)nmol/L和43.5(32.5,56.8)nmol/L,差异有统计学意义(P<0.001);分娩时不同孕周的产妇其妊娠早期血清25-(OH)-D差异无统计学意义(P=0.121)。以25-(OH)-D水平<5th为妊娠早期妇女维生素D严重缺乏指标,不同年龄、不同季节、不同BMI、经产妇和初产妇出现维生素D严重缺乏的概率差异均有统计学意义(P<0.001)。结论妊娠早期低体重、低妊娠年龄、初产有更高的维生素D严重缺乏发生率,不同季节25-(OH)-D有差异(冬<春<秋<夏),妊娠早期维生素D水平和早产不相关。

Objective To investigate the serum 25-hydroxy vitamin D concentrations and related factors in early pregnancy.Methods Plasma was collected in the first trimester from 23 396 pregnant women to investigate the vitamin D level,and its distribution and differences in different age,body maxx index(BMI)and seasons between primipara and multipara.Preterm birth was used as an indicator of clinical outcomes.Vitamin D concentrations were measured using chemiluminescence microparticle immunoassay.Results 25-hydroxy vitamin D level was 42.0(17.6-76.6)nmol/L in totally 23 396 pregnant women with early pregnancy,and 5% and 95% percentile sites of vitamin D level were 20.2 nmol/L and 70.7 nmol/L respectively.There were 18 170(77.7%)primiparas and 5 226(22.3%)multiparas,with the mean age of 30.0(24.0-38.0)years and BMI of 20.7(16.5-27.6)kg/m^2.The number of cases detected in spring(March,April and May),summer(June,July and August),autumn(September,October and November months)and winter(December,January and February)were 5 878,5 554,5 974,and 5 990,respectively,and the vitamin D levels were 40.0(29.3,52.7)nmol/L,46.2(35.6,57.2)nmol/L,43.8(33.1,54.8)nmol/L and 37.2(26.9,49.9)nmol/L respectively,with the difference in vitamin D levels statistically significant among the four seasons(P<0.001).According to BMI,all pregnant women were divided into four groups as BMI<18.5 kg/m^2,18.5 kg/m^2≤BMI≤23.9 kg/m^2,24 kg/m^2≤BMI≤27.9 kg/m^2,BMI≥28 kg/m^2,and the levels of 25-hydroxy vitamin D were 43.5(30.9,56.9)nmol/L,42.1(30.8,53.8)nmol/L,39.9(30.7,50.4)nmol/L and 39.7(30.7,49.4)nmol/L respectively with the difference statistically significant among the four groups.The levels of vitamin D detected in pregnant women with age<25 years,25~29 years,30~34 years,≥35 years were 39.1(28.4,52.3)nmol/L,41.3(30.1,52.9)nmol/L,42.4(31.2,54.1)nmol/L and 43.8(31.9,55.7)nmol/L respectively and the difference was statistically significant(P<0.001).The levels of 25-hydroxy vitamin D in primary and multiparas were 41.6(30.2,52.9)nmol/L and 43.5(32.5,56.8)nmol/L with the difference statistically significant(P<0.001).Among women of different gestational age during childbirth,the differences in serum 25-hydroxy vitamin D in early pregnancy were not statistically significant(P=0.121).The severe deficiency of vitamin D in early pregnancy was defined as serum level of 25-hydroxy vitamin D less than 5th level.There were statistical differences in the probability of severe vitamin D deficiency of different ages,seasons and BMI between primiparas and multiparas.Conclusions Pregnant women of lower weight,lower age and primiparity have higher incidence of the severe vitamin D deficiency in early trimester of pregnancy.There is significant difference in 25-hydroxy vitamin D level among the different seasons(winter<spring <autumn <summer).Vitamin D level in early pregnancy is not associated with preterm birth.