Research Article

Gestational Medication Use, Birth Conditions, and Early Postnatal Exposures for Childhood Asthma

Table 3

Risks for childhood asthma in relation to delivery modes and birth conditions.

ControlsEver asthmaEarly-onset asthmaLate-onset asthma
N (%)§N §OR95%CINOR95%CIN §OR95%CI

Modes of delivery
Vaginal255 (66.2)1281.00611.00671.00
Scheduled CS58(15.1)251.04(0.59, 1.83)131.19(0.49, 2.88)120.97(0.45, 2.09)
Emergent CS72(18.7)381.13(0.70, 1.83)160.76(0.37, 1.57)221.63(0.81, 3.28)
Forceps usage during vaginal delivery
 No250(98.0)1181.00591.00591.00
 Yes5(2.0)92.12(0.57, 7.91)20.41(0.04, 3.95)75.10(0.84, 30.93)
Vacuum usage during vaginal delivery
 No243(95.3)1031.00511.00521.00
 Yes12(4.7)243.68(1.34, 10.1)*102.01(0.47, 8.63)145.16(1.29, 20.60)*
Low birth weight
 No338(90.4)1581.00781.00801.00
 Yes36(9.6)311.73(0.96, 3.1)131.99(0.77, 5.13)181.76(0.81, 3.8)
 2000–2500 gm25(6.7)221.70(0.86, 3.35)91.61(0.56, 4.62)131.60(0.72, 3.55)
 < 2000 gm11(2.9)91.79(0.66, 4.87)44.18(0.65, 26.77)55.69(0.49, 65.67)
for trend0.080.100.09
Preterm delivery
 No356(92.2)1691.00801.00891.00
 Yes30(7.8)241.83(0.98, 3.41)112.47(0.94, 6.50)131.4(0.63, 3.27)
 34–36 wk22(7.2)161.74(0.81, 3.74)82.51(0.82, 7.72) 81.16(0.40, 3.36)
 < 34 wk2(0.7)54.31 (0.81, 2.88)34.80(0.44, 52.14)24.48 (0.39, 51.97)
for trend0.030.040.32

Models are adjusted for parental education, mother’s age at birth of her child, parental history of asthma, parental history of atopy, and in utero maternal smoking.
* .
§Number of subjects does not add up to total n because of missing data.
Early onset: asthma diagnosed ≦3 yr of age.
Late onset: asthma diagnosed >3 yr of age.
Preterm delivery was defined as children born at gestational age less than 37 weeks.