Prevention of preterm labour and delivery

This chapter describes the French national programme for reduction of preterm births which started in 1971. Prevention of preterm labour and delivery in France was the objective of a national policy applied to all pregnant women for 10 years and more than 700,000 pregnancies every year, and which has continued since the end of the initial programme. Prevention is action that must be applied before the beginning of disease. The risk analysis was the first step, and showed that most known risk factors (young age, previous preterm birth, bleeding during pregnancy) could not be changed and could not form the basis of a prevention strategy. Other risk factors were described, particularly lifestyle and severity of work, which promoted uterine contractions. Uterine contractions can be recognized by individual women. Shortening of the cervix is also an important risk factor. The intervention strategy involved modifying lifestyle to reduce the workload of women, thereby reducing uterine contractions and/or premature maturation of the cervix. This national policy was evaluated by two techniques; one was performed on successive representative samples of all pregnant French women in 1972, 1976 and 1981, and repeated in 1988/9, and the second (from 1971 to 1982) involved a longitudinal study in a district hospital and included 16,000 women from the city of Haguenau. Preterm deliveries were significantly reduced in France from 7.9% in 1971 to 5.8% in 1981. The reduction was more significant in 1988-9, with a preterm delivery rate of 4.1%. This was associated with a major reduction in early preterm births (before 32 weeks of gestation): 1.6% of births in 1972, 0.7% of births in 1981 and 0.5% of births in 1988-9. As this intervention was intended for all pregnant women and not as a controlled trial, it was not possible to directly demonstrate a causal relationship between the intervention and the observed effects. However, it is argued that a close relationship exists between the intervention programme and the effective reduction of preterm births in France during that time.