Measuring the invisible: perinatal health outcomes of unregistered women giving birth in Belgium, a population-based study

Table 4 Prematurity (crude rates among No maternal NPR) and Odds Ratios) according to registration status (reference is maternal NPR), stratified by maternal nationality

Maternal Nationality	Per 100 births	OR^a	CI (95%)	*p-value*	aOR^b	CI (95%)	*p-value*
Belgium		cases = 44,936 / n = 661,984			cases = 41,659 / n = 626,412
	10.7	1.6	1.5–1.8	*< 0.0001*	1.4	1.2–1.6	*< 0.0001*
EU15		cases = 3373 / n = 54,330			cases = 2939 / n = 49,798
	11.7	2.2	1.96–2.4	*< 0.0001*	1.7	1.5–1.9	*< 0.0001*
EU27 (without EU15)		cases = 1886 / n = 29,545			cases = 1611 / n = 26,398
	12.2	2.2	1.9–2.5	*< 0.0001*	1.7	1.45–2.05	*< 0.0001*
Eastern Europe		cases = 855 / n = 15,042			cases = 667 / n = 12,470
	7.65	1.4	1.2–1.8	*0.001*	1.2	0.95–1.6	0.11
Turkey		cases = 487 / n = 8374			cases = 430/ n = 74,610
	7.6	1.3	0.8–2.2	0.26	0.91	0.44–1.85	0.79
Maghreb		cases = 1580 / n = 34,647			cases = 1355 / n = 30,611
	7.5	1.7	1.4–2.1	*< 0.0001*	1.6	1.25–2.1	*< 0.0001*
Sub-Saharan Africa		cases = 1905 / n = 26,170			cases = 1557 / n = 22,276
	11.0	1.6	1.4–1.9	*< 0.0001*	1.4	1.2–1.8	*< 0.0001*
South America		cases = 340 / n = 4921			cases = 286 / n = 4283
	7.7	1.15	0.9–1.5	0.31	0.98	0.7–1.42	0.91
Middle East and North/West Asia		cases = 642 / n = 11,008			cases = 489 / n = 8953
Middle East and North/West Asia	8.65	1.6	1.2–2.1	*0.003*	1.6	1.1–2.3	*0.015*
Other		cases = 671 / n = 10,934			cases = 567 / n = 9643
	7.7	1.3	0.96–1.8	0.09	1.4	1.0–2.01	0.07
Outside EU		cases = 5914 / n = 102,109			cases = 4876 / n = 87,764
	8.6	1.6	1.44–1.74	< 0.0001	1.4	1.23–1.55	< 0.0001

^a Crude OR
^b Adjusted OR for maternal age, single, parity, number of incomes and maternal education

ISSN: 1471-2393