Further Observations on Prematurity and Perinatal Mortality in a General Population and in the Population of a Prepaid Group Practice Medical Care Plan

Abstract

The current study reexamines an earlier finding that pregnancy loss in HIP (Health Insurance Plan), a prepaid group practice comprehensive medical are plan, was lower than in NYC''s general population under the care of private physicians. Data for the 3 year period 1955-1957 show that there is a small but significantly lower prematurity rate in HIP than in the comparative group in NYC. Rates per 100 single live births, adjusted for differences in age of mother and ethnic composition are: HIP- 5.7; NYC (private patients) - 6.2. The differential between HIP and NYC in perinatal mortality, as observed in this period, is also statistically significant with HIP having a distinctly lower rate. Adjusted rates per 1000 single live births and fetal deaths (20 weeks or more gestation) are: HIP-23.1; NYC (private patients) - 27.9. These differences could not be explained by a more favorable socio-economic situation in HIP''s population. Other findings, specific for the NYC population, were that economic level and ethnic group exercise strong influences on the proportion of women who receive their obstetrical care from private physicians. Also major differences in prematurity and perinatal mortality rates exist between general service and private physician cases. This holds for both white and non-white groups.