Table 1

Prevalence of SGA in the whole population of babies and in strata of gestational age in Sweden 1987–1993

			SGA stratified by gestational age
	SGA		Term		Preterm		Post-term
	768 059	(2.3%)	676 961	(1.9%)	36 080	(10.1%)	55 018	(3.0%)
	N	Per cent	N	Per cent	N	Per cent	N	Per cent
Newborn babies
Male	393 538	2.33	343 549	1.86	19 635	9.20	30 354	3.24
Female	374 521	2.34	333 412	1.87	16 445	11.26	24 664	2.78
Birth order
First	325 326	3.30	279 426	2.66	18 796	11.67	27 104	4.10
Second	268 998	1.63	242 276	1.31	9 774	8.79	16 948	2.01
≥Third	173 735	1.63	155 259	1.30	7,510	8.07	10 866	1.97
Birth intervals
<1 year	4557	3.55	3841	2.76	415	6.99	301	8.97
1–2 years	77 922	2.00	69 232	1.61	3585	8.23	5105	2.86
>2 years	147 354	1.97	130 979	1.57	5970	9.45	10 405	2.72
‘Only child’	341 906	2.77	298 264	2.20	17 789	11.63	25 853	3.29
First child	196 320	1.97	174 645	1.60	8321	8.45	13 354	2.70
Previous child SGA
Yes	3371	9.58	2913	7.69	259	30.12	196	9.18
No	226 462	1.90	201 139	1.52	9711	8.34	15 615	2.80
‘Only child’	341 906	2.77	298 264	2.20	17 789	11.63	25 853	3.29
First child	196 320	1.97	174 645	1.60	8321	8.45	13 354	2.70
Maternal age
<20	40 735	3.06	35 367	2.49	2485	9.93	2883	4.30
20–24	156 736	2.39	138 232	1.91	7842	9.82	10 662	3.24
25–34	481 689	2.19	425 980	1.76	20 796	9.59	34 913	2.89
>35	88 899	2.69	77 382	2.08	4957	12.04	6 560	2.90
Hypertension	3166	8.69	2648	5.44	383	32.11	135	5.93
Smoking
Non-smoker	541 962	1.77	479 851	1.37	22 603	9.14	39 508	2.41
Light smoker	109 799	3.62	76 327	3.05	5884	11.86	7588	4.40
Heavy smoker	67 454	4.41	58 790	3.79	4234	11.76	4430	5.64
Missing	48 844	2.90	41 993	2.12	3359	11.79	3492	3.78
Marital status
Married or cohabiting	385 173	2.02	342 330	1.61	16,50	9.36	26 343	2.69
Divorced or widowed	27 151	3.03	23 475	2.43	1706	10.67	1970	3.55
Single	355 735	2.63	311 156	2.10	17 874	10.81	26 705	3.33
Maternal origin
Born in Sweden	663 043	2.25	584 683	1.79	30 745	10.19	47 615	2.79
Not born in Sweden	95 393	2.83	84 022	2.30	4749	10.07	6 622	4.27
Missing	9623	2.67	8256	3.02	586	8.02	781	7.30
Maternal education
University	181 083	1.95	160 102	1.52	7367	10.26	13 614	2.57
Secondary	400 363	2.22	353 813	1.77	18 457	9.96	28 093	2.74
Primary	140 186	3.21	122 919	2.31	7631	10.78	9636	3.84
Missing	46 427	2.34	40 127	2.67	2625	9.22	3675	4.82

SGA, small for gestational age.