Table 1.

Study population characteristics.

Characteristic	Cases (N = 218)		Controls (N = 230)		p-Valuea
	N	%	N	%
Mother’s race					0.06
White	205	96.7	218	99.5
Other	7	3.3	1	0.5
Missing	6		11
Mother’s age at delivery (yrs)					0.43
<20	1	0.5	7	3.1
20–24	43	19.9	41	17.9
25–29	83	38.4	81	35.4
30–39	86	39.8	96	41.9
>40	3	1.4	4	1.8
Missing	2		1
Mother’s educationb					0.88
CSE/none	31	14.8	26	11.9
Vocational	17	8.1	15	6.9
O-level	67	31.9	73	33.3
A-level	61	29.1	66	30.1
Degree	34	16.2	39	17.8
Missing	8		11
Mother’s prenatal BMI					0.01
<18.5	7	3.6	11	5.4
18.5–24.9	129	65.5	161	78.5
25–29.9	42	21.3	21	10.2
>30	19	9.6	12	5.9
Missing	21		25
Mother’s age at menarche (yrs)					0.0004
8–11	63	32.5	30	15.2
12–14	119	61.3	153	77.3
≥15	12	6.2	15	7.6
Missing	24		32
Child’s birth order					0.07
First born	110	53.9	98	45.6
Second born	57	27.9	83	38.6
Third born or later	37	18.1	34	15.8
Missing	14		15
	Median	Quartile	Median	Quartile
Child’s BMI at age 7	17.2	15.9–18.9	15.8	14.9–16.9	<0.0001
Child’s age at menarche (yrs)	11	10.8–11.3	12.75	12.2–13.3

^aComparison between cases and controls using logistic regression.

^bCSE = certificate of secondary education, O-level = ordinary level, A-level = advanced level.