Table 2 Participant characteristics at enrollment

Variable

Proportion

% (n)

95% Confidence Interval

Proportion

% (n)

95% Confidence Interval

Parity

 nulliparous

63 (107)

55 – 70

63(52)

53–72

 multiparous

37 (63)

29—45

37 (29)

28–47

Maternal Age

  < 35

81 (137)

^a

67(56)

57–77

  > 35

19(33)

^a

32(26)

23–43

Female gender

100 (170)

100 (84)

Ethnicity

 Caucasian

84.1 (23)

77—89

79(64)

69–87

 Non-Caucasian

15.9 (121)

11—22

21(17)

13–31

Home ownership

 Owns home

52 (88)

42—58

64(52)

55–73

 Rent/other

48 (82)

41—57

35(29)

27–45

Marital Status

 Married/common-law

78 (133)

77—79

89(75)

82–95

 other

22 (38)

18—26

11(9)

4–17

Annual Household Income

  < $60,000

59

52—67

12(10)

7–20

 $60,000 or more

41

33—48

88(74)

80–93

Mean

Range

Mean

Range

Gestational age

27 weeks

8–36 weeks

25 weeks

10–41 weeks

Maternal age

^a

^a

32.4 years

21–42 years