Table 1.

Background characteristics of pregnant women who were offered counseling about prenatal screening

	Web application registrations June 2008–December 2010 (n = 30,549)			Exact numbers (n = 60,038)a
	N	%	Median (range)	N	%
Age (years)	30,095		30 (11–50)
≤19	550	2
20–29	13,394	44
30–39	15,375	51
40–50	776	3
Age category
<36	25,911	86b		47,791	80
≥36	4184	14		12,247	20
Ethnic origine	6083			17,990c
Dutch	4018	66		11,133	62
Surinamese	187	3		817	5
Antillean	150	2		484	3
Cape Verdean	64	1		187	1
Turkish	307	5		974	5
Moroccan	470	8		1116	6
Other	887	15		3279	18
Generatione	6083			17,990c
First-generation immigrants	1880	31		4430	25
Second-generation immigrants	185	3d		2427	13
Native Dutch	4018	66		11,133	62
Parity	30,229		1 (0–14)
Nulliparity	15,065	50
Multiparity 1–3	14,635	48
Multiparity 4–14	529	2
Gravidity	30,182		2 (0–20)
1–2 pregnancies	21,707	72
>2 pregnancies	8475	28
Gestational age (first booking visit)	29,007		9 (5–41)
0–11 weeks (on time)	22,894	79
12–41 weeks (too late)	6113	21
Dutch language proficiency level	28,043
Absent	583	2
Limited	1259	5
Fluent	26,201	93
Urbanity	30,549
Not or less urban	6397	21
Moderately urban	4841	16
Highly urban	19,311	63

^aExact numbers of mothers that gave birth to a living child in the study area from June 2008 to December 2010 [Data request, CBS Statistics Netherlands 2013]

^bHigher representation of pregnant women <36 years old due to more inclusion by midwifery practices (low risk population)

^cExact ethnicity distribution for the study area. To make the study outcomes comparable with the denominator data, only 9 months of the year 2010 were explored

^dUnder-reporting second generation caused by the strict definition of second generation (country of birth of the pregnant women and both partners most be known)

^eEthnicity and immigrant generation variables only registered from April 2010 to December 2010