关键词: font-size:medium, ">血清25（OH）D3水平；婴幼儿喘息；巢式病例对照研究；孕期

Abstract: Objective： To explore the correlation between the serum levels of 25（OH） D3 in the third trimester of pregnancy and infant wheezing before 6 months old. Methods： In this study， a cohort-based nested case-control study was used and 900 pregnant women who delivered in our hospital were collected from 2017 to 2018. A cohort study of pregnant women and infants was established to collect baseline information of pregnant women and infants. Follow-up infants by telephone to 6 months old， including infants with at least one wheezing episode as the case group， and healthy infants without wheezing episodes as the control group after the follow-up. Results： The average serum 25（OH） D3 concentration in the third trimester of pregnancy was （52.5±15.1） nmol·L-1. The level in the case group was lower than that in the control group， and the difference was statistically significant (P＜0.05). Logistic regression analysis showed that elderly parturient women (7.95， 95% CI： 4.23-15.21)， smoke exposure (6.01， 95% CI： 2.24-16.34)， history of allergies (4.13， 95% CI： 1.28-13.34) and late pregnancy serum 25（OH） D3 deficiency (1.89，95% CI：1.80～3.03) are risk factors for wheezing in infants within 6 months old (P<0.05). Conclusion： elderly parturient women， smoke exposure， history of allergies， and vitamin D deficiency during pregnancy are closely related to the episocle of wheezing in infants within 6 months old. Interventions that increase vitamin D levels during pregnancy can reduce the risk of early wheezing episodes in infants.

Key words: font-size:medium, ">Serum 25 (OH) D3 level； Infant wheezing； Nested case-control study； Pregnancy