Modeled exposure to tetrachloroethylene-contaminated drinking water and the risk of placenta-related stillbirths: a case-control study from Massachusetts and Rhode Island

Table 1 Distribution of Selected Characteristics of Cases and Controls

Characteristic	Stillbirth Cases		Controls
	(N = 296)		(N = 783)
	n	%	n	%
State of Birth
Massachusetts	155	52.4	442	56.4
Rhode Island	141	47.6	341	43.6
Year of delivery
1968–1978	165	55.7	278	35.5
1979–1988	79	26.7	293	37.4
1989–1995	52	17.6	212	27.1
Maternal age at delivery (mean, sd)	27.0 (5.9)		27.0 (5.5)
Missing	1		0
Paternal age at delivery (mean, sd)	30.1 (6.8)		29.8 (6.1)
Missing	77		34
Maternal Race
White	153	91.6	623	90.0
Non-white	14	8.4	69	10.0
Missing	129		91
Maternal Educational Level
Less than high school	19	12.8	96	14.1
High school graduate	57	38.3	247	36.2
Some college	28	18.8	175	25.7
College graduate	45	30.2	164	24.0
Missing	147		101
Paternal Educational Level
Less than high school	23	16.3	90	13.8
High school graduate	48	34.0	221	33.9
Some college	19	13.5	139	21.3
College graduate	51	36.2	202	31.0
Missing	155		131
Prenatal care began in first trimester
Yes	94	81.7	485	88.2
No	21	18.3	65	11.8
Missing	181		233
Prior livebirths
Yes	105	62.5	388	56.4
No	63	37.5	300	43.6
Missing	128		95
Prior pregnancy losses
Yes	19	24.4	70	12.9
No	59	75.6	473	87.1
Missing	218		240
Prenatal smoking
Yes	18	31.0	70	23.3
No	40	69.0	230	76.7
Missing	238		483
Prenatal alcoholic beverage consumption
Yes	17	29.8	72	35.0
No	40	70.2	134	65.0
Missing	239		577
Maternal occupational exposure to solvents
Yes	2	3.4	4	2.0
No	57	96.6	197	98.0
Missing	237		582

ISSN: 1476-069X