Table 1

Demographics and characteristics of previous pregnancies by infertility type

Birth year*	Female		Male		Combined		Unknown		Total		Female+Combined
	1977 (1973–1985)		1976 (1973–1987)		1975 (1973–1983)		1976 (1973–1984)		1976 (1973–1984)		1976 (1973–1985)
	n	Per cent	n	Per cent	n	Per cent	n	Per cent	n	Per cent	n	Per cent
BMI
<20	61	13.8	36	11.5	8	10.3	35	10.9	140	12.1	69	13.3
20–24, 99	248	56.1	181	58.0	39	50.0	217	67.6	685	59.4	287	55.2
25–29, 99	102	23.1	80	25.6	21	26.9	65	20.2	268	23.2	123	23.7
>30	31	7.0	15	4.8	10	12.8	4	1.2	60	5.2	41	7.9
Tobacco use
Smoking
Yes	32	7.1	30	9.4	8	10.4	20	93.9	90	7.7	40	7.6
No	420	92.9	290	90.6	69	89.6	307	6.1	1086	92.3	489	92.4
Snuff
Yes	3	99.3	5	1.6	2	2.7	9	2.8	19	1.6	5	1.0
No	447	0.7	313	98.4	73	97.3	319	97.2	1151	98.4	520	99.0
Number of previous pregnancies
0	344	75.4	260	81.5	60	77.9	254	77.2	918	77.7	404	75.8
1–2	101	22.1	55	17.2	14	18.2	64	19.5	234	19.8	115	21.6
≥3	11	2.4	4	1.3	3	3.9	11	3.3	29	2.5	14	2.6
Number of previous miscarriages
0	391	85.7	293	91.8	66	85.7	290	88.1	1040	88.1	457	85.7
1–2	58	12.7	26	8.2	11	14.3	32	9.7	127	10.8	69	12.9
≥3	7	1.5	0	0.0	0	0.0	7	2.1	14	1.2	7	1.3
Number of previous abortions
0	429	94.3	297	93.1	73	96.1	299	90.9	1098	93.1	502	94.5
1	23	5.1	20	6.3	3	3.9	25	7.6	71	6.0	26	4.9
≥2	3	0.7	2	0.6	0	0.0	5	1.5	10	0.8	3	0.6
Number of children
No children	407	90.0	293	92.1	68	89.5	304	93.0	1072	91.4	475	90.0
≥1 child	45	10.0	25	7.9	8	10.5	23	7.0	101	8.6	53	10.0