Prenatal care and the prevention of preterm delivery

Abstract

This paper reports the methods and results of an innovative program of prenatal care, designed to prevent preterm delivery in Clamart, France, during 1976-1981. Rates of preterm delivery among women who entered the prenatal care program early in pregnancy (and, thus, could derive full benefit of the program) were compared with those among two comparison groups: (1) women who entered the same program later in pregnancy; and (2) women who delivered in Paris. In the first comparison, women who entered the program early had significantly lower rates of preterm delivery than did women who entered later, even when stratified by various risk factors, and when high-risk women were eliminated altogether. In the second comparison, the early care group in Clamart did not exhibit the usual inverse relationship between socioeconomic status and rates of preterm delivery. The usual significant inverse relationship was found in the Clamart population as a whole, and in the Paris series.

PIP: This paper reports the methods and results of an innovative program of prenatal care, designed to prevent preterm delivery in Clamart, France, during 1976-1981. Rates of preterm delivery among women who entered the prenatal care program early in pregnancy (and, thus, could derive full benefit of the program) were compared with those among 2 comparison groups: 1) women who entered the same program later in pregnancy; and 2) women who delivered in Paris. In the 1st comparison, women who entered the program early had significantly lower rates of preterm delivery than did women who entered later, even when stratified by various risk factors, and when high-risk women were eliminated altogether. In the 2nd comparison, the early care group in Clamart did not exhibit the usual inverse relationship between socioeconomic status and rates of preterm delivery. It was found in the Clamart population as a whole, and in the Paris series. Youth, primigravidity, low socioeconomic status and a history of preterm delivery are all associated with risk of current preterm delivery. The lower frequency of preexisting risk factors in the early care group does not account for the lower rates of current preterm delivery. A history of preterm delivery was the strongest predictors of prematurity in the current pregnancy. While multigravidae with a history of preterm delivery had a 3-fold increase in the rate of preterm delivery, those who came into care late still had a marked disadvantage over the early care group (relative risk=2.8). The relative risk was 2.3 among multigravidae without past preterm deliveries. While women who have preexisting risk factors have elevated rates of preterm delivery, they constitute a minority of the population (24% in Clamart). Consequently, women at low risk have more preterm deliveries in absolute numbers than do high-risk women. In Clamart there is very little increase in preterm delivery in the lowest social stratum.