TABLE 2—

Risk of Low Birth Weight and Preterm Birth Associated With Long-Acting Reversible Contraception Use at Title X Clinics in the Woman’s County of Residence: Colorado, 2012

		Low Birth Weight			Preterm Birth
LARC Use	Sample Size, No.	Incidence, %	OR (95% CI)	P	Incidence, %	OR (95% CI)	P
Quartile 1 (≤ 4.96%)	16 035	8.77	1.00 (Ref)		9.36	1.00 (Ref)
Quartile 2 (4.97%–8.75%)	14 373	8.56	0.94 (0.82, 1.08)	.35	8.42	0.82 (0.71, 0.97)	.04
Quartile 3 (8.76%–12.4%)	15 133	8.63	0.96 (0.83, 1.10)	.47	8.91	0.89 (0.78, 1.03)	.15
Quartile 4 (> 12.4%)	15 494	8.29	0.92 (0.80, 1.07)	.24	8.81	0.81 (0.70, 0.96)	.02

Note. CI = confidence interval; LARC = long-acting reversible contraception. We obtained all estimates from a generalized estimating equation, with adjustment for maternal age, race/ethnicity, body mass index (weight in kilograms divided by the square of height in meters), education, income, marital status, prenatal care, smoking status, history of gonorrhea, history of chlamydia, history of congenital anomaly, and interpregnancy interval.