Table 4.

Adjusted odds ratios^* for association between categorical model covariates and thyroid hormone prescription (≥1/year) in young adulthood (ages 25.5–37.0 years; N=629,806)

	OR	95% CI	P value
Gender
Male	1.00
Female	7.29	6.90, 7.71	<0.0001
Fetal growth (SD)
<−2	1.04	0.93, 1.17	0.45
−2 to <−1	1.09	1.03, 1.16	0.004
−1 to <0	1.04	1.00, 1.09	0.07
0 to <1	1.00
1 to <2	1.00	0.94, 1.07	0.89
≥2	1.01	0.91, 1.12	0.90
Maternal age (years)
<20	1.00
20–24	0.94	0.87, 1.02	0.13
25–29	0.95	0.88, 1.03	0.24
30–34	0.91	0.83, 0.99	0.04
≥35	0.89	0.80, 1.00	0.05
Maternal marital status in 1990
Married/cohabiting	1.00
Never married	0.96	0.90, 1.03	0.27
Divorced	1.01	0.95, 1.07	0.76
Widowed	1.12	0.94, 1.32	0.20
Maternal education in 1990 (years)
Compulsory high school or less (≤9)	1.00
Practical high school or some theoretical high school (10–11)	1.06	1.01, 1.11	0.02
Theoretical high school and/or college (≥12)	1.10	1.04, 1.16	0.002
Family income in 1990
Lowest quartile	1.00
Second quartile	0.97	0.92, 1.03	0.36
Third quartile	0.99	0.94, 1.05	0.85
Highest quartile	0.99	0.94, 1.06	0.85
Maternal prescription of thyroid hormones (≥1/year) during follow-up period
0	1.00
≥1	3.07	2.92, 3.22	<0.0001

^*The model included gestational age at birth, fetal growth, age, gender, maternal age at delivery, maternal marital status, maternal education, family income, and maternal prescription of thyroid hormones (≥1/year) during the follow-up period (7/1/2005 through 12/31/2009). The reference category for all odds ratios is indicated by an OR of 1.00.