A preterm birth prevention project in Nova Scotia, Canada

Community-based, population-focused preterm birth prevention programs - a review

PURPOSE

Preterm birth (PTB) is the leading cause of perinatal morbidity and mortality worldwide. Being born too early contributes to approximately 70% of neonatal mortality and approximately half of long-term neurodevelopmental disabilities. Various PTB prevention programs have been described going back more than 30 years, and some have described possible success in decreasing the rate of PTB. In addition, there are also PTB prenatal care clinics in many parts of the world, each with the singular goal of reducing the PTB rate in their region. Interventions can be directed at all women for primary prevention and reducing the risk of PTB or used to mitigate risk in women identified to be at increased risk.

METHODS

A Medline and ClinicalTrials.gov ( www.clinicaltrials.gov ) search was performed (1982-2018), using preterm birth prevention program as the primary medical subject heading, reporting randomized clinical trials, quasi-experimental trials, and analytic studies (including retrospective and prospective cohort studies). We also searched Google for preterm birth prevention programs and prenatal care clinics published on-line.

RESULTS

Some prevention programs have reported success in lowering rates of PTB, principally using historical controls although the majority were not followed by improved outcomes.

CONCLUSION

Increasing knowledge and the use of social media to enhance education should now enable greater effectiveness of new programs. Development of regional and national PTB prevention programs should now be considered.

Effects of socioeconomic position and clinical risk factors on spontaneous and iatrogenic preterm birth

BACKGROUND

The literature shows a variable and inconsistent relationship between socioeconomic position and preterm birth. We examined risk factors for spontaneous and iatrogenic preterm birth, with a focus on socioeconomic position and clinical risk factors, in order to explain the observed inconsistency.

METHODS

We carried out a retrospective population-based cohort study of all singleton deliveries in Nova Scotia from 1988 to 2003. Data were obtained from the Nova Scotia Atlee Perinatal Database and the federal income tax T1 Family Files. Separate logistic models were used to quantify the association between socioeconomic position, clinical risk factors and spontaneous preterm birth and iatrogenic preterm birth.

RESULTS

The study population included 132,714 singleton deliveries and the rate of preterm birth was 5.5%. Preterm birth rates were significantly higher among the women in the lowest (versus the highest) family income group for spontaneous (rate ratio 1.14, 95% confidence interval (CI) 1.03, 1.25) but not iatrogenic preterm birth (rate ratio 0.95, 95% CI 0.75, 1.19). Adjustment for maternal characteristics attenuated the family income-spontaneous preterm birth relationship but strengthened the relationship with iatrogenic preterm birth. Clinical risk factors such as hypertension were differentially associated with spontaneous (rate ratio 3.92, 95% CI 3.47, 4.44) and iatrogenic preterm (rate ratio 14.1, 95% CI 11.4, 17.4) but factors such as diabetes mellitus were not (rate ratio 4.38, 95% CI 3.21, 5.99 for spontaneous and 4.02, 95% CI 2.07, 7.80 for iatrogenic preterm birth).

CONCLUSIONS

Socioeconomic position and clinical risk factors have different effects on spontaneous and iatrogenic preterm. Recent temporal increases in iatrogenic preterm birth appear to be responsible for the inconsistent relationship between socioeconomic position and preterm birth.

Impact of participation in the Halifax County Preterm Birth Prevention Project

OBJECTIVES

(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.

METHODS

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.

RESULTS

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).

CONCLUSION

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.