Table 1

Baseline characteristics and TBFVL parameters in all BLT and BILD study infants, stratified for term pregnancy and asthma in pregnancy

Maternal asthma,
term infants
(BLT cohort, n=373)*
No maternal asthma,
term infants
(BILD cohort, n=193)
Maternal asthma,
preterm infants
(BLT cohort, n=33)*
Maternal asthma, term infants
(BILD cohort, n=20)
Mean (SD)Mean (SD)P value†Mean (SD)Mean (SD)P value‡
tPTEF:tE%§32.00 (9.8)35.00 (10.5) 0.0022 28.55 (8.4)34.45 (8.8)0.1603
Birth order1.7 (1.0)1.7 (0.8)0.22991.6 (0.9)1.5 (0.8)0.5826
Age (days)48.1 (10.8)35.8 (5.2) <0.0001 65.2 (22.6)36.9 (5.6) <0.0001
Weight gain (kg per day)0.031 (0.012)0.028 (0.011)0.07630.030 (0.008)0.025 (0.009)0.0544
Maternal age (years)30.0 (5.2)32.5 (4.2) <0.0001 30.2 (4.4)32.4 (2.9) 0.0200
n (%) n (%) n (%) n (%)
Male sex190 (51)101 (52)0.790419 (57)13 (65)0.2561
Exclusive breast feeding224 (59)181 (94) <0.0001 17 (48)19 (95) 0.0014
Tobacco exposure in pregnancy37 (10)17 (9)0.76344 (12)0
Caesarean section107 (29)30 (15) 0.0004 26 (81)9 (45)0.1347
  • BLT infants were all born to mothers with asthma, stratified for term and preterm. BILD infants were term born babies, stratified for no maternal asthma and maternal asthma.

  • *Maternal asthma, term infants (BLT) n=373; and maternal asthma, preterm infants (BLT) n=33. 1 BLT infant did not have perinatal outcomes available.

  • †Comparing maternal asthma, term infants from BLT cohort versus no maternal asthma and term infants from BILD cohort. P values <0.05 in bold.

  • ‡Comparing maternal asthma, term infants from BLT cohort versus maternal asthma and term infants from BILD cohort. P values <0.05 in bold.

  • §tPTEF:tE%=percentage time to peak tidal expiratory flow divided by total expiratory time.

  • BILD, Bern Infant Lung Development; BLT, Breathing for Life Trial; TBFVL, tidal breathing flow–volume loop.