Table 1.

Descriptive Statistics for Other Key Factors Used as Control Variables in Analyses

	Full Sample		Zero Parity (no prior births)		Parity One (one prior birth)
	(n=847)		(n=718)		(n=193)
	(48,736 person-weeks)		(43,853 person-weeks)		(4,883 person-weeks)
Measure	Mean	SD	Mean	SD	Mean	SD
Relationship status
No relationship*	0.41	0.49	0.42	0.49	0.30	0.46
Special relationship*	0.51	0.50	0.51	0.50	0.53	0.50
Engaged*	0.08	0.26	0.07	0.25	0.17	0.37
Socio-demographic characteristics
Personal information
African American*	0.26	0.44	0.24	0.42	0.46	0.50
Age at baseline*	19.18	0.58	19.17	0.58	19.27	0.55
High religious importance*	0.56	0.50	0.55	0.50	0.60	0.49
School enrolment
Dropped out of high school/not enrolled*	0.04	0.20	0.03	0.17	0.13	0.33
Completed high school/not enrolled*	0.16	0.36	0.13	0.34	0.34	0.47
Enrolled in high school*	0.13	0.34	0.13	0.33	0.16	0.37
Enrolled in 2-year college or vocational program*	0.30	0.46	0.31	0.46	0.27	0.44
Enrolled in 4-year college*	0.37	0.48	0.40	0.49	0.11	0.31
Household structure
Childhood public assistance*	0.29	0.45	0.26	0.44	0.55	0.50
Receiving public assistance*	0.16	0.36	0.10	0.30	0.67	0.47
Biological mother less than 20 years old at first birth*	0.28	0.45	0.25	0.43	0.54	0.50
Grew up with two parents (both bio or bio/step)*	0.63	0.48	0.65	0.48	0.38	0.48
Mother’s education less than high school graduate*	0.06	0.23	0.05	0.21	0.13	0.33
Prior sexual, contraceptive, and pregnancy experiences
Age at first sex 16 or less*	0.39	0.49	0.34	0.47	0.85	0.36
Number of sexual partners 2 or more*	0.48	0.50	0.44	0.50	0.86	0.34
Ever had sex without birth control*	0.33	0.47	0.27	0.44	0.85	0.36
Number of prior pregnancies 2+*	0.13	0.34	0.05	0.23	0.80	0.40

Notes: All measures are dichotomous. An * indicates statistically significant (p<.05) difference between zero parity and parity one respondents; two-sample t tests