Prenatal diagnosis in Sweden 2011 to 2013—a register-based study

Petersson, Kerstin; Lindkvist, Marie; Persson, Margareta; Conner, Peter; Åhman, Annika; Mogren, Ingrid

doi:10.1186/s12884-016-1165-8

BMC Pregnancy and Childbirth

Table 2 Background characteristics and pregnancy outcomes in the Swedish Pregnancy Register 2011 to 2013 (N = 284,789)

From: Prenatal diagnosis in Sweden 2011 to 2013—a register-based study

Variable	Total		2011		2012		2013		Test of difference^a
	N = 284,789		n = 88,140		n = 96,043		n = 100,606
	n	%	n	%	n	%	n	%
Maternal age^b, primiparous women (years)
Mean (SD)^c	28.83 (5.12)		28.78 (5.17)		28.82 (5.14)		28.87 (5.07)		0.053
Min-max	13.49–56.30		13.52–52.64		13.78–56.30		13.49–52.89
Median (IQR)^d	28.64 (7.07)		28.66 (7.08)		28.59 (7.05)		28.67 (7.04)
Maternal age^b, multiparous women (years)
Mean (SD)^c	31.72 (4.90)		32.29 (4.89)		32.21 (4.90)		32.16 (4.89)		<0.001
Min-max	15.00–57.00		17.07–53.25		16.41–54.47		15.67–57.34
Median (IQR)^d	32.30 (6.88)		32.41 (6.91)		32.28 (6.84)		32.23 (6.89)
Maternal age^b in age-groups (years)
< 20	3976	1.4	1369	1.6	1319	1.4	1288	1.3
20–24	38,832	13.6	11,990	13.6	13,222	13.8	13,611	13.5
25–29	84,129	29.5	25,578	29.0	28,393	29.6	30,158	30.0
30–34	95,772	33.6	29,463	33.4	32,243	33.6	34,066	33.9
35–39	50,717	17.8	16,215	18.4	17,010	17.7	17,492	17.4
40–44	10,705	3.8	3323	3.8	3625	3.8	3757	3.7
> 44	583	0.2	167	0.2	213	0.2	203	0.2
Body mass index (kg/m²)
Mean (SD)^c	24.79 (4.65)		24.75 (4.62)		24.82 (4.67)		24.81 (4.66)		0.002
Min-max	13.03–71.63		13.82–62.06		13.63–67.22		13.03–71.63
Median (IQR)^d	23.80 (5.00)		23.74 (5.41)		23.81 (5.45)		23.81 (5.52)
< 18.5	6838	2.5	2044	2.4	2328	2.5	2466	2.5
18.5–24.99	163,856	59.2	50,787	59.7	55,203	58.9	57,866	58.9
25–29.99	70,440	25.4	21,478	25.3	23,870	25.5	25,092	25.5
30–34.99	25,166	9.1	7526	8.8	8573	9.2	9067	9.2
35.39.99	7899	2.9	2374	2.8	2734	2.9	2791	2.8
≥ 40	2759	1.0	836	1.0	969	1.0	954	1.0
Educational level
Elementary school	20,860	8.7	6662	9.4	6870	8.5	7328	8.4	<0.001
High school	95,564	40.0	27,821	39.4	32,660	40.3	35,083	40.1
University	122,623	51.3	36,155	51.2	41,432	51.2	45,036	51.5
Main occupation
Employed	195,880	70.3	59,890	70.3	66,622	70.5	69,368	70.1	<0.001
Student	31,021	11.1	9697	11.4	10,364	11.0	10,960	11.1
Parental leave	20,469	7.3	6082	7.1	6911	7.3	7475	7.5
Unemployed	15,163	5.4	4955	5.8	4996	5.3	5212	5.3
Sick leave	4421	1.6	1241	1.5	1557	1.6	1623	1.6
Other	11,686	4.2	3300	3.9	4013	4.2	4373	4.4
Country of birth
Sweden	221,398	79.4	70,376	81.8	74,187	78.9	76,835	77.8	<0.001
Other Nordic countries^e	2374	0.8	613	0.8	832	0.8	929	0.8
Europe^f	12,861	4.6	3486	4.0	4481	4.8	4900	5.0
Africa	10,782	3.9	2780	3.2	3658	3.9	4344	4.4
Asia	25,597	9.2	6886	8.0	8976	9.5	9735	9.9
Other	5902	2.1	1917	2.2	1940	2.1	2045	2.1
Smoking 3 months prior to pregnancy	38,854	13.8	12,134	13.9	13,285	14.0	13,435	13.5	0.004
Smoking at first ANC^g visit	15,874	5.6	5062	5.8	5475	5.7	5337	5.4	<0.001
Smoking at 32 weeks of gestation	11,990	4.2	3923	4.5	4133	4.3	3934	3.9	<0.001
Use of snuff 3 months prior to pregnancy	9954	3.5	2530	2.9	3506	3.7	3918	3.9	<0.001
Use of snuff at first ANC^g visit	2858	1.0	793	0.9	945	1.0	1120	1.1	<0.001
Use of snuff at 32 weeks of gestation	1721	0.6	548	0.6	561	0.6	612	0.6	0.572
Alcohol screening (AUDIT)^h	245,544	88.1	74,712	86.7	81,408	86.7	89,424	90.6	<0.001
AUDIT-score^j
Mean (SD)^c	2.19 (2.19)		2.28 (2.22)		2.20 (2.22)		2.09 (2.15)
Min-max	0–40		0–39		0–40		0–40
Median (IQR)^d	2.00 (2)		2.00 (2)		2.00 (2)		2.00 (3)
≤ 5p	229,854	94.0	69,110	93.6	76,327	93.8	84,417	94.4	<0.001
≥ 6p	14,751	6.0	4704	6.4	5044	6.2	5003	5.6
Self-rated health prior to pregnancy	241,854	84.9	70,633	80.1	82,594	86.0	88,627	88.1
Very good	72,321	29.9	19,838	28.1	24,472	29.6	28,011	31.6	<0.001
Good	141,251	58.4	41,299	58.5	48,441	58.6	51,511	58.1
Neither good nor poor	20,425	8.4	6793	9.6	6962	8.4	6670	7.5
Poor	6325	2.6	2174	3.1	2197	2.7	1954	2.2
Very poor	1532	0.6	529	0.7	522	0.6	481	0.5
Counselling due to fear of childbirth	21,595	7.6	6518	7.5	7186	7.5	7891	7.9	0.001
Treatment of psychiatric disorder	17,724	6.3	5122	5.9	6061	6.4	6541	6.5	<0.001
Gestational age (days)
Mean (SD)^c	278.0 (13.8)		278.0 (13.9)		277.8 (13.9)		278.1 (13.7)		<0.001
Min-max	154–301		155–301		154–301		154–301
Median (IQR)^d	280.00 (13.00)		280.00 (13.00)		280.00 (13.00)		280.00 (13.00)
Mode of delivery	283,660	99.6	87,915	99.7	95,594	99.5	100,151	99.5
Vaginal	217,898	76.8	67,277	76.5	73,333	76.7	77,288	77.2	<0.001
Instrumental	19,177	6.8	6208	7.1	6616	6.9	6353	6.3
Caesarean section	46,585	16.4	14,430	16.4	15,645	16.4	16,510	16.5
Caesarean section (CS)
Elective CS^j	20,272	43.6	6321	43.9	6718	43.0	7233	43.9	0.193
Emergency CS^j	26,214	56.4	8085	56.1	8897	57.0	9232	56.1
Birth weight (grams)^k
Mean (SD)^c	3542 (556)		3540 (557)		3543 (556)		3543 (556)		0.352
Min-max	300–6640		300–6050		305–6270		300–6640
Median (IQR)^d	3550 (670)		3550 (675)		3550 (674)		3550 (670)

^aTest of difference between years using One-Way Anova test on numeric variables, and Pearsons’s Chi-Square test for categorical variables
^bMaternal age at delivery
^cSD = Standard Deviation
^dIQR = Interquartile Range
^eOther Nordic countries includes Norway, Finland, Iceland and Denmark
^fThe Nordic countries are excluded
^gAntenatal care
^hAssessment of use of alcohol prior to pregnancy with screening instrument Alcohol Use Disorder Identification Test (AUDIT)
ⁱ AUDIT score ranging from 0 to 40
^jCaesarean section
^kSingletons exclusively included in analysis

Back to article page

ISSN: 1471-2393

Contact us

Submission enquiries: bmcpregnancyandchildbirth@biomedcentral.com
General enquiries: ORSupport@springernature.com