Effects of ultrasound pregnancy dating on neonatal morbidity in late preterm and early term male infants: a register-based cohort study

Table 4 Adjusted^a odds ratios (OR) with 95 % confidence intervals (95 % CI) for prematurity-related adverse outcomes by male sex at birth in gestational week 35–36, and cohort ratios (CR) for the change in male risk before and after the implementation of ultrasound for pregnancy dating in Sweden

Outcome	Birth Cohort 1973–1978 Odds Ratio^a,b (95 % CI)	Birth Cohort 1995–2010 Odds Ratio^a,b (95 % CI)	Cohort Ratios: Ratio of Male ORs 1995–2010 to 1973–1978 (95 % CI)
Neonatal death	1.15 (0.91–1.45)	0.95 (0.71–1.26)	0.82 (0.57–1.19)
Apgar score <7 at 5 min	1.08 (0.91–1.28)	1.26 (1.10–1.45)	1.17 (0.94–1.45)
Pneumothorax	1.70 (1.10–2.62)	2.27 (1.66–3.11)	1.34 (0.78–2.28)
RDS^c	1.74 (1.40–2.16)	1.89 (1.56–2.28)	1.08 (0.81–1.45)
Other respiratory conditions	1.31 (1.12–1.54)	1.60 (1.48–1.72)	1.22 (1.02–1.45)
Hyperbilirubinemia	1.12 (1.03–1.20)	1.18 (1.12–1.23)	1.05 (0.96–1.15)