THE ASSOCIATION OF PRIMIPARITY WITH INTRAUTERINE GROWTH-RETARDATION

The role of parity in the epidemiology of intrauterine growth retardat ion (IUGR) is not well understood, as some risk factors for IUGR are a ssociated with young age and primiparity, and some are more frequent a mong older multiparous women. This paper examines the unique role of p rimiparity in the etiology of IUGR in a series of 25614 singleton birt hs in the southern part of Israel. The rates of IUGR were 3.5% among p rimiparae and 1.7% in multiparae, (Risk ratio=1.99,95% confidence inte rval, 1.69-2.35). Maternal age was associated with IUGR only among pri miparae but not in multiparae. Of the obstetric factors examined, the following were found to be significantly associated with IUGR: hyperte nsion, prior infertility, oligohydramnios, gross fetal congenital anom alies, and being a female fetus. After simultaneous adjustment for the se risk factors by multiple logistic regression analysis, the odds rat io associated with parity was 1.62 (95% confidence interval, 1.30-2.01 ), suggesting that primiparity constitutes an independent risk factor for IUGR.