TABLE 3—

Results of Case–Control Logistic Regression Analysis of Socioeconomic Differences in Overall and Live-Birth Odds of Down Syndrome: Paris, France, 1983–2002

	Total Birthsa		Total Birthsa		Live Births		Live Births
	Unadjusted OR (95% CI)	Pb	Adjusted ORc (95% CI)	Pb	Unadjusted OR (95% CI)	Pb	Adjusted ORc (95% CI)	Pb
Occupational category		.01		.70		<.001		<.001
Professional	1.0		1.0		1.0		1.0
Intermediate	0.9 (0.7, 1.1)		1.1 (0.9, 1.3)		1.3 (1.0, 1.9)		1.5 (1.1, 2.1)
Administrative, public service	0.7 (0.6, 0.9)		1.0 (0.8, 1.2)		1.6 (1.2, 2.2)		1.9 (1.3, 2.6)
Otherd	0.9 (0.7, 1.2)		1.0 (0.7, 1.4)		2.0 (1.3, 3.1)		2.0 (1.3, 3.1)
No occupation	0.9 (0.7, 1.0)		1.1 (0.9, 1.4)		2.3 (1.7, 3.1)		2.4 (1.7, 3.3)
Geographic origin		.71		.76		<.001		<.001
France	1.0		1.0		1.0		1.0
North Africa	1.1 (0.9, 1.4)		0.9 (0.7, 1.2)		2.2 (1.7, 2.8)		1.5 (1.1, 2.0)
Other Africa	1.0 (0.7, 1.3)		1.1 (0.8, 1.6)		1.7 (1.2, 2.5)		1.3 (0.9, 2.0)
Other	1.0 (0.9, 1.2)		1.0 (0.9, 1.3)		1.1 (0.9, 1.5)		1.0 (0.7, 1.3)

Note. OR = odds ratio; CI = confidence interval. Odds ratios refer to odds of a Down syndrome birth (cases) relative to a birth involving one of the following anomalies (controls): congenital dislocation of the hip, cleft palate, syndactyly, clubfoot, angioma, congenital abnormalities of the integument, or anorectal anomalies.

^aLive births, pregnancy terminations, and stillbirths.

^b Wald tests of significance of the overall effect of maternal occupation or geographic origin.

^cAdjusted for maternal age, profession, and geographic origin. Fractional polynomials were used in adjusting for maternal age.

^dArtisan, small business owner, shopkeeper, shop assistant, service worker, skilled worker, or unskilled worker.