Table 2.

Antepartum death rate in males and females by birthweight percentiles and gestational age category

	Male infants		Female infants		RRa	(95% CI)
	(n = 895 272)	%	(n = 847 559)	%
Birthweight <p10 (SGA)
25‐27 wk GA	397/79 442	0.50	371/75 691	0.49	1.02	(0.89‐1.17)
28‐31 wk GA	303/78 863	0.38	206/75 223	0.27	1.40	(1.17‐1.67)
32‐36 wk GA	370/78 017	0.47	264/74 710	0.35	1.34	(1.15‐1.57)
37‐42 wk GA	503/73 106	0.69	420/70 774	0.59	1.16	(1.02‐1.32)
Birthweight p10‐p90 (normal weight)
25‐27 wk GA	277/719 424	0.04	304/677 826	0.04	0.86	(0.73‐1.01)
28‐31 wk GA	404/718 042	0.06	422/676 696	0.06	0.90	(0.79‐1.03)
32‐36 wk GA	597/713 388	0.08	563/673 002	0.08	1.00	(.89‐1.12)
37‐42 wk GA	937/671 723	0.14	978/640 051	0.15	0.91	(0.83‐1.00)
Birthweight ≥p90 (LGA)
25‐27 wk GA	31/96 406	0.03	29/94 042	0.03	1.04	(0.63‐1.73)
28‐31 wk GA	46/96 243	0.05	44/93 850	0.05	1.02	(0.67‐1.54)
32‐36 wk GA	36/95 757	0.04	24/93 409	0.03	1.46	(0.87‐2.45)
37‐42 wk GA	131/93 090	0.14	122/90 754	0.13	1.05	(0.82‐1.34)
All birthweights
25‐27 wk GA	705/895 272	0.08	704/847 559	0.08	0.95	(0.85‐1.05)
28‐31 wk GA	753/893 148	0.08	672/845 769	0.08	1.06	(0.96‐1.18)
32‐36 wk GA	1003/887 162	0.11	851/841 121	0.10	1.12	(1.02‐1.22)
37‐42 wk GA	1571/837 919	0.19	1520/801 579	0.19	0.99	(0.92‐1.06)

Abbreviations: CI, confidence interval; LGA, large‐for‐gestational age; RR, relative risk ratio; SGA, small‐for‐gestational age.

^aRR calculated with fetus at risk approach, meaning the numerator is all neonates with antepartum death in each stratum and the denominator all women remaining pregnant at the beginning of the gestational age stratum in each birthweight category.