Table 2.

Socio-demographic and medical background data on the study population^a

	Mothers ≤ 39 n = 71,472		Mothers 40–44 n = 35,329		Mothers ≥ 45 n = 2229		P-value1	P-value2	P-value3	P-value4
	min-max (mean/sd)		min-max (mean/sd)		min-max (mean/sd)
Maternal age, min-max (mean/sd)	14–39 (31.45/4.54)		40–44 (41.41/1.19)		45–55 (45.92/1.39)		< 0.001	< 0.001	< 0.001	< 0.001
	n	%	n	%	n	%	P-value1	P-value2	P-value3	P-value4
Civil status							< 0.001	< 0.001	< 0.001	< 0.001
Married/ cohabiting	64,059	89.6	30,106	85.0	1802	80.8
Single status at registration	7413	10.4	5323	15.0	427	19.2
Parity							0.001	< 0.001	0.664	0.126
Primiparous	15,660	21.9	7417	20.9	497	22.3
Multiparous	55,812	78.1	28,012	79.1	1732	77.7
Worked during pregnancy							< 0.001	< 0.001	< 0.001	0.004
Unemployed/ student/ other	17,103	27.4	6418	20.8	454	23.9
Full time	27,543	44.2	16,219	52.5	964	50.8
Part time	17,717	28.4	8267	26.8	478	25.2
Tobacco use during pregnancy							< 0.001	< 0.001	0.004	0.383
Yes	8329	12.3	3588	10.8	210	10.2
Mother’s BMI (registration)							< 0.001	< 0.001	< 0.001	0.003
Normal	35,306	56.2	16,156	53.2	905	48.9
Underweight	1165	1.9	291	1.0	21	1.1
Overweight	17,117	27.3	9338	30.8	611	33.0
Obese	9185	14.6	4566	15.0	314	17.0
Chronic illnessb							0.725	0.890	0.440	0.422
Yes	15,035	21.0	7440	21.0	484	21.7
ART							< 0.001	< 0.001	< 0.001	< 0.001
Yes	1894	2.6	2813	7.9	249	11.2

^aNumbers may not add up to the total due to partially missing data

^be.g. Diabetes, Hypertension, Arthritis, SLE, Kidney disease, Epilepsy, Asthma, Ulcerative colitis

¹Across all age groups

²≤39 vs. 40–44

³≤39 vs. ≥45

⁴40–44 vs. ≥45