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Trending elective preterm deliveries using administrative data
Lisa M Korst1, Moshe Fridman, Michael C Lu
1Department of Obstetrics and Gynecology, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA. korst@usc.edu
Insights
A new method identifies
Area of Science:
- Obstetrics and Gynecology
- Public Health
- Health Services Research
Background:
- Preterm birth (PTB) remains a significant concern in maternal and child health.
- Identifying elective PTBs is crucial for understanding delivery rationales.
- Administrative data offers a scalable approach to PTB analysis.
Purpose of the Study:
- To develop and apply a methodology for identifying and analyzing elective preterm births (PTBs) using administrative data.
- To provide a framework for exploring reasons behind early deliveries.
- To establish a method for monitoring trends in elective PTBs.
Main Methods:
- Utilized California linked birth cohort data from 1999, 2002, and 2005.
- Identified singleton PTBs (gestational age ≥24 and <37 weeks) using birth certificate data.
- Employed a hierarchical approach to classify elective PTBs based on medical interventions (caesarean or induction) after excluding 'hard' indications.
Main Results:
- Over 1.3 million deliveries were analyzed, with 7.2% being preterm.
- Elective PTBs increased by 27.7% over the study period.
- Elective late PTB rates rose from 10.5% to 13.5% of all late PTBs, with 'soft' indications including prior pelvic floor repair and mental health conditions.
Conclusions:
- A robust methodology was developed to identify and trend elective PTBs using administrative data.
- This method enables the exploration and monitoring of strategies for elective PTB prevention.
- The findings highlight the need for further investigation into the rationales for non-medically indicated early deliveries.
Background:
We propose a methodology for identifying and analysing 'elective' preterm births (PTBs) using administrative data, and apply this methodology to California data with the objective of providing a framework to further explore the potential rationales for early delivery.
Methods:
Using the California linked birth cohorts for 1999, 2002 and 2005, singleton PTBs were identified using birth certificate gestational age ≥ 24 and <37 weeks. Through a hierarchical scheme that first removed cases with standard or 'hard' indications for early delivery (e.g. severe preeclampsia, placenta previa), cases of 'elective' PTB were identified with coding for medical intervention, that is, elective caesarean or labour induction. We calculated rates of elective PTB, with subanalyses of early (<34 weeks of gestational age) and late PTB (34 to <37 weeks of gestational age) using hierarchical logistic regression models.
Results:
Of 1 387 565 singleton deliveries, 99 614 (7.2%) were preterm. Elective PTBs increased 27.7% over the 6-year study period, with nearly all cases confined to the late PTB stratum; elective late PTB rates rose from 10.5% to 13.5% of all late PTBs (P < 0.0001). Indications for delivery in this Elective Group ('soft indications') included prior pelvic floor repair, mental health conditions, fetal anomalies, malpresentation and oligohydramnios. Six per cent of patients with a late PTB had a medical intervention with no hard or soft indication for delivery.
Conclusions:
Using administrative data, we developed a method for identifying and trending the proportion of PTBs that is 'elective'. This method can be used to explore and monitor potential strategies for the prevention of elective PTB.
