Table 1.

Percentage of feeding type of twin individuals according to the birth year of twins

	Full breast-feeding		Partial breast-feeding		Formula feeding		Missing
	n	%	n	%	n	%	n
1968–1974 (n = 729)
0 months	83	11.8	285	40.5	335	47.7	26
1 month	59	9.7	230	38.0	317	52.3	123
2 months	50	8.7	181	31.5	344	59.8	154
3 months	35	6.1	173	30.1	366	63.8	155
4 months	21	3.8	146	26.1	392	70.1	170
5 months	17	3.2	128	24.2	384	72.6	200
6 months	11	2.1	120	23.2	386	74.7	212
1975–1984 (n = 935)
0 months	177	19.5	531	58.4	202	22.2	25
1 month	143	16.8	480	56.3	230	27.0	82
2 months	133	16.2	374	45.5	315	38.3	113
3 months	100	12.4	365	45.3	341	42.3	129
4 months	54	6.8	321	40.3	421	52.9	139
5 months	49	6.4	276	36.2	438	57.4	172
6 months	43	5.8	257	34.9	436	59.2	199
1985–1994 (n = 1,230)
0 months	253	21.1	813	67.9	132	11.0	32
1 month	194	16.8	802	69.3	161	13.9	73
2 months	190	16.8	668	59.0	274	24.2	98
3 months	161	14.4	604	53.9	355	31.7	110
4 months	121	11.2	502	46.4	459	42.4	148
5 months	100	9.4	476	44.8	487	45.8	167
6 months	92	8.8	460	43.7	500	47.5	178
1995–2003 (n = 1,129)
0 months	222	20.0	735	66.1	155	13.9	17
1 month	180	16.7	739	68.6	159	14.8	51
2 months	169	15.9	634	59.5	262	24.6	64
3 months	148	14.0	586	55.2	327	30.8	68
4 months	115	11.0	489	46.8	440	42.2	85
5 months	113	11.0	432	41.9	487	47.2	97
6 months	106	10.5	394	39.1	508	50.4	121