Table II.

Digit ratio and estimated time to pregnancy according to baseline characteristics in 696 women: the MIREC study.

Characteristic	n (%)	Digit ratio				TTP
		Right hand		Left hand		Median (25–75%)a	Pe
		Mean	Pd	Mean	Pd
Age, years			0.90		0.24		<0.001
<30	160 (23.0)	0.986		0.976		2 (1–4)
30–34	274 (39.4)	0.984		0.978		2 (1–5)
35–39	210 (30.2)	0.984		0.980		2 (1–6)
≥40	52 (7.4)	0.986		0.987		5.5 (1–18)
Education			0.03		0.33		0.88
High school or less	39 (5.6)	0.975		0.972		1 (1–7)
Some college classes	28 (4.0)	0.989		0.988		2.5 (1–5.5)
College trade diploma	143 (20.5)	0.991		0.978		2 (1–6)
University degree	486 (69.8)	0.983		0.979		2 (1–5)
Ethnicity			<0.001		0.01		0.05
White	590 (84.8)	0.986		0.979		2 (1–5)
Black	20 (2.8)	0.953		0.952		2 (1–3)
Latin	18 (2.6)	0.978		0.971		8.5 (2–12)
Chinese	11 (1.6)	0.978		0.986		1 (1–6)
Other	57 (8.2)	0.982		0.982		4 (1–8)
Household income			0.16		0.13		0.32
<$60 000	129 (18.5)	0.978		0.973		2 (1–5)
$60 001–100 000	257 (37.0)	0.985		0.978		2 (1–5)
>$100 000	287 (41.2)	0.987		0.981		2 (1–6)
No response	23 (3.3)	0.989		0.983		2 (1–3)
Parity conditional on gravidity			0.80		0.38		0.06
No prior pregnancy	206 (29.5)	0.983		0.976		3 (1–6)
Prior pregnancy without live birth(s)	101 (14.5)	0.985		0.977		2 (1–7)
Prior pregnancy with live birth(s)	389 (56.0)	0.985		0.980		2 (1–5)
Maternal smoking			0.63		0.56		0.21
Never	451 (64.8)	0.984		0.978		2 (1–6)
Former	163 (23.4)	0.984		0.981		1 (1–4)
Currentb	82 (11.8)	0.988		0.976		2 (1–6)
Pre-pregnancy BMIc			0.15		0.35		0.09
<24.9	423 (60.8)	0.986		0.979		2 (1–5)
25–29.9	130 (18.7)	0.979		0.974		2 (1–6)
>30	101 (14.5)	0.987		0.979		3 (1–7)

^aMedian TTP in months (25–75 percentiles).

^bIncludes women who quit during the first trimester of pregnancy.

^cn = 654 because of missing values.

^dANOVA F test.

^eLog-rank test.