Birth outcomes across the spectrum of maternal age: dissecting aging effect versus confounding by social and medical determinants

Table 2 Adverse outcomes in study population by maternal age groups (N = 8509)

*Adverse Pregnancy Outcomes*	< 20 years		20–29 years		30–39 years		40+ years		Total		P-value^a
*Adverse Pregnancy Outcomes*	N	%	N	%	N	%	N	%	N	%
Total	907	100	4305	100	2960	100	337	100	8509	100
Spontaneous preterm delivery											0.546
No	736	81.1	3561	82.7	2417	81.7	275	81.6	6989	82.1
Yes	171	18.9	744	17.3	543	18.3	62	18.4	1520	17.9
Cesarean delivery (n = 8420)											< 0.001
No	725	80.8	3045	71.6	1731	58.9	158	47.2	5659	67.2
Yes	172	19.2	1206	28.4	1206	41.1	177	52.8	2761	32.8
Low birth weight											0.037
No	659	72.7	3240	75.3	2147	72.5	242	71.8	6288	73.9
Yes	248	27.3	1065	24.7	813	27.5	95	28.2	2221	26.1

ISSN: 1471-2393