孕妇产前血清25（OH）D3水平与产后出血关联性研究

目的：分析目前南京地区孕妇的维生素D状况，并评价其与产后出血发生的关系。方法选择2012年3月至2015年2月期间在我院产科进行孕检的2794例孕妇为研究对象，采集受试孕妇外周血5 mL，低温离心分离，于-80°C冰箱保存，并同时收集其基本信息及后续分娩方式。采用酶联免疫法测定25(OH)D浓度，运用条件Logistic回归分析25(OH)D水平与产后出血发生的关联程度。结果2794例孕妇中，1752例(62.7%)孕妇的血清25(OH)D<50 nmol/L，处于维生素缺乏状态；血清25(OH)D水平的中位数和四分位间距为43.80 nmol/L和35.60~58.40 nmol/L；不同年龄段的孕妇其血清25(OH)D水平比较差异有统计学意义(P<0.05)，年龄<25岁的孕妇其血清25(OH)D水平低于25~32岁和>32岁的孕妇；有不良孕产史的孕妇，其血清25(OH)D水平高于无不良孕产史的孕妇(P<0.05)；且不同季节检测的25(OH)D水平差异有统计学意义(P<0.01)，其中夏秋季检测的25(OH)D水平相对较高45.65 nmol/L (36.78~59.43 nmol/L)、45.50 nmol/L (36.88~61.43 nmol/L)]，而春冬季相对较低(40.40 nmol/L (33.65~54.80 nmol/L)、42.80 nmol/L (35.60~55.75 nmol/L)]；在产后出血的孕妇中，高龄、高BMI、经产妇、不良孕产史、子宫肌瘤、疾病史和低维生素D可能为产后出血的危险因素；关联分析及亚组分析结果显示，相对于血清25(OH)D水平处于50~75 nmol/L的孕妇，血清25(OH)D水平<50 nmol/L和>75 nmol/L的孕妇并未显著增加产后出血的风险。维生素D缺乏(<50 nmol/L)在子宫肌瘤和无疾病史的孕妇中，可显著增加产后出血的风险(OR=5.96和1.29；95%CI=1.98~17.92和1.01~1.63)。结论南京孕晚期妇女存在维生素D水平不足或缺乏状况，维生素D不足或缺乏未能显著增加产后出血的风险，而低水平的血清25(OH)D在子宫肌瘤和无疾病史的孕妇中，可能增加产后出血的风险。

Relationship between prenatal serum vitamin D level and postpartum haemorrhage for pregnant women

Objective To analyze the status of vitamin D in pregnant women in Nanjing, and to evaluate the re-lationship between vitamin D level and the occurrence of postpartum hemorrhage. Methods A total of 2 794 pregnant women who underwent pregnancy test in our hospital from March 2012 to February 2015 were selected as research ob-jects. Peripheral blood (5 mL) were collected from the test pregnant women, and then centrifuged at low temperature and stored at-80 °C until assayed. The subjects’basic information and delivery mode were collected. The serum 25-hydroxy vitamin D (25(OH)D) levels was measured by enzyme linked immunosorbent assay. The relationship between 25(OH)D level and postpartum haemorrhage were analyzed by logistic regression. Results Among 2 794 cases, there were 1 752 cases (62.7%) of 25(OH)D<50 nmol/L, in a vitamin deficiency state. The median and range interquartile of serum 25(OH)D level were 43.80 nmol/L and 35.60~58.40 nmol/L. There were significant differences in the serum 25(OH)D level between pregnant women of different age periods (P<0.05), with the serum 25(OH)D level of age <25 years group significantly lower than that of 25~32 years group and >32 years group. Pregnant women with history of ad-verse pregnancy had higher 25(OH)D levels than those without history of adverse pregnancy (P<0.05). The 25(OH)D levels also showed statistically significant difference in different detection seasons (P<0.01), and the 25(OH)D levels were relatively higher in summer and autumn and relatively lower in spring and winter, which were 45.65 nmol/L (36.78~59.43 nmol/L), 45.50 nmol/L (36.88~61.43 nmol/L), 40.40 nmol/L (33.65~54.80 nmol/L, 42.80 nmol/L (35.60~55.75 nmol/L), respectively. Advanced age, obesity, high body mass index (BMI), pregnancy history, abnormal pregnan-cy history, uterine fibroids, disease history, and lower Vitamin D may be the risk factors for the subsequent postpar-tum haemorrhage. Correlation analysis and subgroup analysis showed that, compared with that in pregnant women with 25(OH)D level of 50~75 nmol/L, the risk of postpartum haemorrhage in pregnant women with serum 25(OH)D lev-els<50 nmol/L and>75 nmol/L was not significantly increased. Vitamin D deficiency (<50 nmol/L) in pregnant women with uterine fibroids and without disease history resulted in significantly increased risk of postpartum hemorrhage (OR=5.96 and 1.29; 95% CI=1.98~17.92 and 1.01~1.63). Conclusion Vitamin D deficiency is a common phenomenon in the third trimester of pregnancy for pregnant women in Nanjing area. There is no evidence indicating that Vitamin D defi-ciency is associated with increased risk of postpartum haemorrhage. However, low serum 25(OH)D level in pregnant women with uterine fibroids and without disease history may increase the risk of postpartum hemorrhage.