A retrospective cohort study of the characteristics of unsuccessful operative vaginal deliveries

Vacuum extraction is successful in 95% of cases with an occiput posterior position: the results of a prospective, multicenter study

BACKGROUND

Occiput posterior position is associated with labor arrest, need for operative delivery, and failed instrumental vaginal delivery, with resulting adverse peripartum outcomes. Vacuum extraction is the most commonly performed type of instrumental delivery worldwide.

OBJECTIVE

This study aimed to investigate the outcome of vacuum extraction in fetuses with sonographically confirmed occiput posterior position before the procedure.

STUDY DESIGN

Singleton pregnancies at term with sonographically confirmed fetal occiput posterior position before the vacuum extraction were enrolled in 3 academic maternity units. Fetal head station was assessed using transperineal sonography measuring the angle of progression and the head-perineum distance. The primary outcome was failed vacuum extraction, defined as the need for cesarean delivery. Secondary outcomes included adverse maternal and/or adverse neonatal outcomes and complicated vacuum extraction, with the latter defined as failed vacuum extraction or at least 3 out of the following 6 parameters: 5-minute Apgar score <7, neonatal acidemia, admission to the neonatal intensive care unit, neonatal trauma, postpartum hemorrhage, and obstetrical anal sphincter injuries.

RESULTS

Among the 98 patients included in the study, vacuum extraction was successful in 94 (96%). Logistic regression analysis showed that the measurement of the head-perineum distance was the only factor independently associated with failed vacuum extraction (odds ratio, 1.25; 95% confidence interval, 1.02-1.55; P=.03), with an area under the curve of 0.79 (P=.04). A head-perineum distance cutoff value of 38.5 mm discriminated between successful and failed vacuum extraction, yielding a sensitivity of 75.0% (3/4), specificity of 84.0% (79/94), positive likelihood ratio of 4.7, and negative likelihood ratio of 0.3.

CONCLUSION

Vacuum extraction is successful in 95% of fetuses with occiput posterior position confirmed at ultrasound. The head-perineum distance measured at transperineal ultrasound has a significant albeit weak association with the outcome of vacuum extraction.

Accessing Anonymised Data from Ireland's Maternal and Newborn Clinical Management System for Research Purposes

Background

Since 2016, maternity units across Ireland have been switching from paper clinical notes to an electronic health record called the Maternal and Newborn Clinical Management System (MN-CMS). Currently, four units have implemented the MN-CMS: Cork University Maternity Hospital (CUMH), University Hospital Kerry (UHK), Rotunda Hospital and National Maternity Hospital (NMH). The MN-CMS provides opportunity for new data-driven discovery to answer important research questions on maternal and child health.

Aim

Provide detailed information on how a request can be made to access anonymised MN-CMS data for research purposes, as well as current timelines involved from initial request to data access.

Methods

A request to collaborate should be made to the clinical lead within each maternity unit where data is being requested in the first instance. A detailed protocol and data collection sheet should be drafted and forwarded to the National Information Governance Group for approval. A Data Protection Impact Assessment should be completed, and permission to access data from each maternity unit must be applied for separately from each unit's local Ethics Committee. Upon receipt of ethical approval, an application to the Local Information Governance Group must be submitted if requesting data from CUMH and/or UHK. Data can then be extracted and anonymised by the data manager at the respective unit and transferred securely to relevant project personnel.

Results

The timeline from initial request to data access can range from approximately 6-12 months, depending on number of maternity units from which data is being requested and number of variables being requested from each unit.

Conclusions

Accessing MN-CMS data for research can be a complex process. A national standardised process for managing the data is needed. This would allow a clear pathway to be developed for accessing data to facilitate new data-driven discovery in the area of maternal and child health.