Table 1. Demographic characteristics and contraceptive use by incident pregnancy.

	Column % (n)	Rate per 100 woman yrs (No. pregnancies/woman yrs)	Unadjusted Rate Ratio (95% CI)	P-value
Overall pregnancy incidence	(352)	9.6 (48/501)	–	–
Age in years				0.24
18–20	28.7 (101)	11.3 (16/142)	1
21–25	38.9 (137)	9.9 (19/192)	0.89 (0.46–1.72)
26–30	20.2 (71)	10.7 (11/103)	0.94 (0.44–2.03)
31–35	12.2 (43)	3.1 (2/64)	0.28 (0.06–1.23)
Race				0.53
Black	98.9 (348)	9.5 (47/496)	1
Mixed	1.1 (4)	19.4 (1/5)	2.05 (0.28–14.8)
Contraception supplied at site
Yes	68.8 (242)	8.3 (29/348)	0.68 (0.38–1.21)
No	31.3 (110)	12.4 (19/153)	1	0.20
Contraception use at screening
Consistent condom use in 6 months prior to screening
Yes	57.1 (201)	8.6 (25/290)	0.78 (0.44–1.38)
No	42.9 (151)	10.9 (23/211)	1	0.39
Any current male/female condom use
Yes	79.6 (280)	10.4 (42/403)	1.72 (0.73–4.05)
No	20.5 (72)	6.1 (6/98)	1	0.19
Current use of oral contraceptive pills
Yes	13.4 (47)	15.4 (10/65)	1.80 (0.90–3.62)
No	86.6 (305)	8.7 (38/436)	1	0.12
Current use of injectable contraceptive
Yes	58.5 (206)	6.4 (19/296)	0.46 (0.26–0.81)
No	41.5 (146)	14.2 (29/205)	1	0.007
Contraception use during follow up (time varying)
Consistent condom use
Yes	–*	8.5 (26/328)	0.60 (0.34–1.07)	0.09
No		12.0 (22/173)	1
Any current male/female condom use
Yes	–*	8.8 (33/375)	0.76 (0.41–1.41)	0.40
No		11.9 (15/126)	1
Use of oral contraceptive pills
Yes	–*	16.7 (13/78)	2.02 (1.07–3.83)	0.04
No		8.3 (35/423)	1
Use of injectable contraceptive
Yes	–*	6.6 (22/330)	0.41 (0.23–0.71)	0.002
No		15.5 (26/168)	1

^*Data from multiple time points contribute to this statistic, number for each time point not shown.