Table 1.

Characteristics of mother and newborns according to mode of conception

	Spontaneous conception (N = 269,986)*		Non-spontaneous conception (N = 7057)*		p-value***	IVF/ICSI		p-value***	IVF		p-value***
	N	%**	N	%		N	%**		N	%**
Maternal age (yrs)
≤24	28,660	10.7	60	0.9	<0.0001	15	0.3	<0.0001	11	0.5	<0.0001
25–29	58,974	21.9	466	6.6		293	5.7		121	5.5
30–34	91,841	34.2	1932	27.4		1355	26.1		552	25.2
35–39	71,969	26.8	2886	41.0		2258	43.5		904	41.3
40+	17,332	6.5	1700	24.1		1268	24.4		602	27.5
Mean (SD)	31.8 (5.4)		36.3 (4.8)
Paternal age (yrs)
≤ 29	39,714	15.4	176	2.6	<0.0001	84	1.7	<0.0001	41	2.0	<0.0001
30–34	75,452	29.3	1177	17.4		806	16.2		351	16.8
35–39	84,796	32.9	2558	37.9		1902	38.2		780	37.2
40–44	41,460	16.1	1865	27.6		1447	29.1		624	29.8
45+	16,071	6.2	979	14.5		736	14.8		298	14.2
Mean (SD)	35.3 (6.0)		39.0 (5.6)
Maternal education
University	72,515	27.0	2802	39.8	<0.0001	2120	40.8	<0.0001	786	35.8	<0.0001
High school degree	117,422	43.7	3139	44.5		2306	44.4		1020	46.5
Primary/intermediate school or no education	78,684	29.3	1108	15.7		770	14.8		388	17.7
Paternal education
University	52,240	20.1	2041	30.0	<0.0001	1582	31.5	<0.0001	614	29.1	<0.0001
High school degree	110,415	42.6	3060	44.9		2214	44.1		925	43.9
Primary/intermediate school or no education	96,835	37.3	1713	25.1		1225	24.4		568	27.0
Cityzenship of the mother
Italian	190,834	70.8	6244	88.6	<0.0001	4574	88.1	<0.0001	1895	86.5	<0.0001
Foreign	78,840	29.2	805	11.4		617	11.9		296	13.5
Geographical area of foreign citizenship
Europe	25,874	32.8	416	51.7		332	53.8		160	54.0
Africa	23,476	29.8	157	19.5		116	18.8		61	20.6
Asia	16,530	21.0	93	11.6		71	11.5		30	10.1
Southern America	9473	12.0	90	11.2		63	10.2		36	12.2
USA, Canada	184	0.2	8	1.0		5	0.8		2	0.7
Other or missing	3303	4.2	41	5.1		30	4.9		7	2.4
Number of ultrasound examination
0	4016	1.5	75	1.1	<0.0001	57	1.1	<0.0001	29	1.3	<0.0001
1	3305	1.2	40	0.6		19	0.4		7	0.3
2	9716	3.6	66	0.9		41	0.8		12	0.6
3	88,116	32.6	1006	14.3		635	12.2		271	12.4
4–6	108,839	40.3	2430	34.4		1757	33.8		765	34.9
7–9	55,994	20.7	3440	48.8		2690	51.7		1110	50.6
Amniocentesis
No	234,318	89.0	5621	81.5	<0.0001	4088	80.7	<0.0001	1714	80.0	<0.0001
Yes	28,986	11.0	1273	18.5		979	19.3		429	20.0
Chorionic villus sampling
No	246,824	94.0	6164	89.9	<0.0001	4507	89.4	<0.0001	1928	90.4	<0.0001
Yes	15,705	6.0	696	10.1		534	10.6		205	9.6
Course of pregnancy
Phisiological	252,253	93.4	5787	82.0	<0.0001	4250	81.9	<0.0001	1792	81.7	<0.0001
Pathological	16,870	6.2	1253	17.8		937	18.1		400	18.3
Status
Liveborn	269,528	99.8	7004	99.3	<0.0001	5158	99.5	NE	2177	99.3	NE
Stillborn	117	0.0	17	0.2		13	0.3		7	0.3
Early neo-natal mortality 0–7 days	190	0.1	21	0.3		8	0.2		6	0.3
Neo-natal mortality 8–28 days	101	0.0	13	0.2		2	0.03		2	0.1
Sex
Male	139,190	51.6	3542	50.2	0.0237	2585	49.7	0.0088	1112	50.7	0.4163
Female	130,796	48.4	3515	49.8		2614	50.3		1082	49.3
Birth
Single	263,707	97.7	4721	66.9	<0.0001	3283	63.2	<0.0001	1362	62.1	<0.0001
Twin	6279	2.3	2336	33.1		1916	36.9		832	37.9
Birthweight (gr)
< 1000	904	0.3	134	1.9	<0.0001	107	2.1	<0.0001	49	2.2	<0.0001
1000–1499	1539	0.6	243	3.4		190	3.7		84	3.8
1500–2499	15,553	5.8	1695	24.0		1340	25.8		576	26.3
2500–3999	237,388	87.9	4787	67.8		3433	66.0		1425	65.0
4000+	14,602	5.4	198	2.8		129	2.5		60	2.7
Mean (SD)	3240 (518.9)		2819 (716.2)
Gestational age at birth
< 32	2289	0.9	348	4.9	<0.0001	274	5.3	<0.0001	120	5.5	<0.0001
32–36	16,054	5.9	1688	24.0		1325	25.5		602	27.4
37–40	210,764	78.2	4420	62.7		3163	60.9		1308	59.6
41+	40,528	15.0	591	8.4		432	8.3		164	7.5

NE not evaluable

*In some cases the sum does not add up the total due to missing values

**Column percent

***Heterogeneity Chi–square test