Table 1.

Demographic Data of Participating Women

	Cases	Controls
Number of participants	49	48
Age at enrolment (mean ± SD)	35.6 ± 6.0	36.6 ± 5.1
Smokers	14	13
Number of overall pregnancies	196	71*
Partus per participant (mean ± SD)	0.37 ± 0.7	1.48 ± 0.6*
Number of miscarriages	178	0*
8th–12th week of gestation	173	0
13th–20th week of gestation	5	0
Number of miscarriages per participant (mean ± SD)	3.6 ± 1.2	0
Women with two consecutive miscarriages	5	0
Women with –three to six miscarriages	44	0
Ratio of successful pregnancies	0.07	1.00*

The study included 49 Caucasian women with a history of two consecutive or —three to six nonconsecutive early pregnancy losses and 48 healthy parous women who had no previous history of pregnancy loss. Cases and controls were unrelated and were matched for age, smoking behavior, and ethnic background.

*P < 0.0001.

SD, standard deviation.