Impact of participation in the Halifax County Preterm Birth Prevention Project

(1). To determine if participation in the Halifax County Preterm Birth Prevention Project (HCPBPP) reduced the risk of preterm birth; (2). to evaluate the degree to which specific components of the HCPBPP contributed to preterm-birth risk reduction.

A nested case-control study was conducted among women residing in Halifax County who gave birth at the IWK Grace Health Centre during the final year of the HCPBPP. Cases, defined as women who delivered preterm (<37 weeks), and controls, defined as women who delivered at full term, were recruited to complete interviewer-administered questionnaires. Three controls per case were sequentially selected. The exposures of interest were overall participation and compliance with specific components of the program. Univariate and multivariate statistical methods were employed to evaluate the effect of exposure to the preterm-birth prevention program.

Seventy cases and 210 controls were enrolled in the study. Although 82% of subjects participated in some aspect of the HCPBPP, only 8% of high-risk and 6% of low-risk women complied fully with program recommendations. Exposure to project educational strategies or pelvic examinations provided no protective benefit for preterm birth in low-risk or high-risk women. However, compliance with prenatal care providers recommendations to restrict activity or monitor for uterine contractions by self-palpation was associated with a marked reduction in the risk of preterm birth among low-risk women (odds ratio, 0.20; 95% confidence interval, 0.08 0.50).

Although full participation in the HCPBPP protocol was limited, the findings of this case-control study suggest that activity restriction and uterine activity monitoring by self-palpation may reduce the likelihood of preterm birth in women with no identifiable risk factors for prematurity.