Table 1: Relation between maternal smoking and neonatal characteristics.*

NonsmokersSmokers 𝑃

Number of subjects4020
Maternal age (y) 2 7 ± 5 2 5 ± 4 NS
Number of parities 2 ± 1 1 . 7 ± 0 . 8 NS
Duration of gestation (wk) 4 0 ± 1 4 0 ± 1 NS
Birth weight (kg) 3 . 4 ± 0 . 4 3 . 3 ± 0 . 3 NS
Sex of neonate
 Male23 (57%)10 (50%) NS
 Female 17 (43%)10 (50%)
Apgar score
 1st minute 8 . 3 ± 0 . 4 8 . 4 ± 0 . 4 NS
 5th minute 9 . 5 ± 0 . 5 9 . 4 ± 0 . 5
Cord blood
 pH 7 . 3 2 ± 0 . 0 7 7 . 3 ± 0 . 6 NS
 PO2 (mm Hg) 2 5 ± 7 2 2 ± 3 NS
 PCO2 (mm Hg) 4 4 ± 8 4 8 ± 1 0 NS
 Erythropoietin (IU/L) 2 4 ± 9 6 1 ± 4 6 .001

*Data reported as mean ± S E or number (percent).
NS, not significant ( 𝑃 > . 0 5 ).