TABLE 1

Demographic Data

VariableEntire Cohort (n = 450 Twin Pairs)Data With Zygosity (n = 252 Twin Pairs)Pa
GA, wkb29.12 ± 2.4229.70 ± 2.25<.001
BW, gb1285.58 ± 442.901397.46 ± 442.93<.001
Male gender, n (%)480 (53.30)273 (54.20).618
Concordant gender, n (%)604 (67.10)210 (65.63).065
RDS, n (%)612 (68.00)306 (60.70)<.001
IVH, n (%)137 (15.20)62 (12.30).008
NEC, n (%)89 (9.90)48 (9.50).763
BPD, n (%)192 (21.30)88 (17.50).002
  • a Comparison between the cohorts with and without zygosity data.

  • b Mean ± SD.