Table 1

Descriptive characteristics and unadjusted infant feeding trends in the birth cohort

Background, maternal and infant health characteristics	Full cohort		Characteristic as % of cohort		Exclusive breast feeding (at first review)		Mixed breast feeding (at first review)
Background, maternal and infant health characteristics	n	(1997–2009) (%)	1997 (%)	2009 (%)	1997 (%)	2009 (%)	1997 (%)	2009 (%)
Mother's age
<20 years	56 921	8	8	7	6	6	3	3
20–24 years	130 522	18	18	19	12	12	6	6
25–29 years	193 247	27	32	27	23	25	9	9
30–34 years	210 922	29	29	27	33	35	11	12
35–39 years	109 044	15	11	16	37	37	11	13
40+	19 795	3	2	4	43	37	11	16
Mother's country of birth
Africa	9103	1.3	1	2	73	64	11	22
Asia	20 152	2.8	2	4	48	50	18	30
Australasia	2932	0.4	0.4	0.4	68	71	6	11
British Isles	662 568	91.6	94	86	36	33	3	8
Europe	21 724	3.0	2	6	59	66	5	14
North America	4605	0.6	1	1	64	68	7	16
South America	1068	0.1	0.1	0.2	92	64	5	27
Not known	1488	0.2	0.2	0.4	100	-	0	-
Mother's smoking status at first visit
Managerial/professional	195 716	27	23	29	63	55	4	10
Intermediate	162 841	23	22	21	40	34	4	7
Routine/semiroutine occupation	207 308	29	32	26	23	26	3	6
Other/economically inactive	157 775	22	22	24	27	28	4	8
Marital status—parents
Married	397 227	55	62	50	46	50	4	12
Cohabiting	208 625	29	21	35	28	28	3	7
Joint registration—different addresses	71 709	10	9	11	17	15	2	5
Single parent	44 619	6	7	4	16	15	2	7
Mother's smoking status at first visit
Non-smoker	422 444	58	47	69	46	42	4	10
Smoker	135 860	19	20	16	18	14	3	5
Other/unknown	165 336	23	33	15	39	35	4	9
Mode of delivery
Normal/spontaneous	448 131	62	69	55	37	38	3	8
Instrumental	85 820	12	11	12	41	39	4	10
Breech	3431	0	0.6	0.4	31	30	5	16
Caesarean—elective	62 996	9	7	10	34	33	5	11
Caesarean—emergency	101 294	14	11	14	36	33	5	12
Other unknown	21 968	3	2	9	20	0	0	20
Parity
First time mother	321 815	44	43	46	36	36	4	8
Multiparous mother	401 825	56	57	54	39	37	4	10
Neonatal admission
Not admitted	607 293	84	66	83	38	37	3	9
Admitted for up to 2 days	26 110	4	3	3	29	28	4	9
Admitted for more than 2 days	44 346	6	5	5	30	28	7	12
Other/unknown	45 891	6	25	9	37	38	4	9
Postnatal stay in hospital
2 days or shorter	319 623	44	34	52	34	36	3	8
3 days or longer	381 420	53	65	39	40	37	4	13
Other unknown	22 597	3	1	9	42	33	7	16
					39	38	6	9
Derived variables
Mother's background—Onomap
British birth and British origin	641 174	89	92	82	36	33	3	7
British birth and non-British origin	18 093	3	2	3	43	36	7	13
Non-British birth and British origin	23 708	3	3	4	58	61	6	13
Non-British birth and non-British origin	31 772	4	2	9	57	62	16	23
Mother of unknown birth/origin	8893	1	1	2	45	46	10	18
Parental background—Onomap
Both parents of British origin	604 964	84	86	78	38	35	3	8
Mother of British origin and father of non-British origin	17 579	2	2	4	53	51	5	12
Mother of non-British origin and father of British origin	15 555	2	2	3	55	50	5	13
Both parent of non-British origin	29 674	4	3	7	49	58	16	24
One parent of unknown origin	55 868	8	8	8	18	23	2	10
Maternal religious background—Onomap
Christian	687 489	95	96.7	92.7	37	36	3	8
Muslim	18 758	3	1.8	3.3	48	49	18	28
Buddhist	4319	1	0.4	1.0	42	45	12	26
Sikh	1757	0	0.2	0.3	55	59	15	26
Hindu	1924	0	0.1	0.5	47	47	4	20
Jewish	448	0	0.1	0.1	44	48	6	14
Not applicable	8945	1	0.7	2.1	45	46	10	18
Area deprivation—SIMD 2006
SIMD 1: Most deprived	181 612	25	26	25	19	23	3	8
SIMD 2	145 486	20	20	21	31	30	3	8
SIMD 3	134 500	19	19	19	41	39	4	9
SIMD 4	130 752	18	17	18	50	48	5	10
SIMD 5: Least deprived	129 719	18	18	17	61	54	5	12

SIMD, Scottish Index for Multiple Deprivation.