Table 2.

Estimated probabilities and 95% CI of obstetric and neonatal morbidity according to maternal age adjusted for: obesity, assisted reproductive technology and geographical origin. Probabilities were estimated by modelling the relationship between maternal age and outcome (see Fig. 2)

		Maternal age				P 1
	< 25	25–34	35–39	40–44	≥ 45
Unfavourable pregnancy outcome	0.06 [0.05–0.08]	0.05 [0.04–0.05]	0.07 [0.06–0.07]	0.09 [0.08–0.11]	0.16 [0.12–0.23]	< 0.001
Hospitalisation during pregnancy a	0.16 [0.14–0.19]	0.11 [0.11–0.12]	0.14 [0.13–0.15]	0.18 [0.16–0.20]	0.28 [0.23–0.34]	< 0.001
Pre-eclampsia	0.01 [0.01–0.02]	0.01 [0.01–0.02]	0.02 [0.01–0.02]	0.02 [0.02–0.03]	0.04 [0.02–0.08]	0.02
Gestational diabetes b	0.01 [0.00–0.01]	0.02 [0.02–0.02]	0.03 [0.03–0.04]	0.05 [0.04–0.06]	0.10 [0.06–0.16]	< 0.001
Caesarean delivery	0.14 [0.13–0.16]	0.18 [0.18–0.19]	0.27 [0.25–0.28]	0.37 [0.34–0.41]	0.62 [0.52–0.71]	< 0.001
Preterm birth	0.08 [0.07–0.10]	0.07 [0.06–0.07]	0.07 [0.07–0.08]	0.08 [0.07–0.10]	0.10 [0.08–0.12]	0.01
Newborn small-for-gestational age	0.18 [0.17–0.21]	0.14 [0.13–0.14]	0.14 [0.13–0.15]	0.18 [0.16–0.21]	0.34 [0.24–0.46]	< 0.001
Newborn transfer c	0.18 [0.16–0.21]	0.12 [0.11–0.12]	0.14 [0.13–0.15]	0.18 [0.16–0.20]	0.29 [0.23–0.36]	< 0.001

¹ test of the association with age as a continuous variable

^a more than 1 day

^b requiring hospitalisation

^c in paediatric unit or neonatal intensive care unit