Cervical ripening at home or in hospital during induction of labour: the CHOICE prospective cohort study, process evaluation and economic analysis

Abstract

Background: Around one in three pregnant women undergoes induction of labour in the United Kingdom, usually preceded by in-hospital cervical ripening to soften and open the cervix.

Objectives: This study set out to determine whether cervical ripening at home is within an acceptable safety margin of cervical ripening in hospital, is effective, acceptable and cost-effective from both National Health Service and service user perspectives.

Design: The CHOICE study comprised a prospective multicentre observational cohort study using routinely collected data (CHOICE cohort), a process evaluation comprising a survey and nested case studies (qCHOICE) and a cost-effectiveness analysis.

The CHOICE cohort set out to compare outcomes of cervical ripening using dinoprostone (a prostaglandin) at home with in-hospital cervical ripening from 39 weeks of gestation. Electronic maternity record data were collected from 26 maternity units. Following pilot analysis, the primary comparison was changed to ensure feasibility and to reflect current practice, comparing home cervical ripening using a balloon catheter with in-hospital cervical ripening using any prostaglandin from 37 weeks of gestation. Analysis involved multiple logistic regression for the primary outcome and descriptive statistics for all other outcomes.

The qCHOICE study reported descriptive statistics of quantitative survey data and thematic analysis of focus group and interview data.

The economic analysis involved a decision-analytic model from a National Health Service and Personal Social Services perspective, populated with CHOICE cohort and published data. Secondary analysis explored the patient perspective utilising cost estimates from qCHOICE data.

Setting: Twenty-six United Kingdom maternity units.

Participants: Women with singleton pregnancies at or beyond 37 weeks of gestation having induction with details of cervical ripening method and location recorded.

Main outcome measures: CHOICE cohort Neonatal unit admission within 48 hours of birth for 48 hours or more.

qCHOICE: Maternal and staff experience of cervical ripening.

Economic analysis: Incremental cost per neonatal unit admission within 48 hours of birth avoided.

Data sources: Electronic maternity records from 26 maternity units; survey and interviews with service users/maternity staff; focus groups with maternity staff; published literature on economic aspects.

Results: CHOICE cohort: A total of 515 women underwent balloon cervical ripening at home and 4332 underwent in-hospital cervical ripening using prostaglandin in hospitals that did not offer home cervical ripening. Neonatal unit admission within 48 hours of birth for 48 hours or more following home cervical ripening with balloon was not increased compared with in-hospital cervical ripening with prostaglandin. However, there was substantial uncertainty with the adjusted analysis consistent with a 74% decrease in the risk through to an 81% increase.

qCHOICE: Important aspects of service users’ experience of home cervical ripening were quality of information provided, support and perception of genuine choice.

Economic analysis: Home cervical ripening with balloon led to cost savings of £993 (−£1198, −£783) per woman and can be considered the dominant strategy.

Limitations: Circumstances relating to the COVID-19 pandemic limited the number of participating maternity units and the duration for which units participated. Low numbers of women having at-home cervical ripening limited the power to detect differences in safety, effectiveness, cost and acceptability between study groups.

Conclusions: Home cervical ripening using balloon catheter may be as safe for babies as using prostaglandins in hospital in low and moderate-risk groups, but there is substantial uncertainty. Home cervical ripening with balloon is likely to be cost saving. Impacts on workload, service user and staff experiences were complex.

Future work: Future research should focus on optimising experience and logistics of home cervical ripening within busy maternity services.

Study registration: Current Controlled Trials ISRCTN32652461.