Does improved quality of care affect maternal health outcomes? Focusing on adequate prenatal care, off-hours delivery, access to labor facilities, and severe maternal morbidity

Abstract

Background: Even though most Korean births are delivered in health facilities with skilled birth professionals in attendance, the maternal mortality ratio, which is an indicator of quality of maternal care, is still higher compared with the average for OECD countries. The majority of maternal deaths occur during labor, childbirth, and the postpartum period; therefore, it is necessary to find the risk factors influencing maternal mortality during and after delivery, and to develop eplicable indicators of maternal mortality in cases of rare events, such as severe maternal morbidity. However, there have been few studies of severe maternal morbidity during delivery hospitalization as indicators of quality of maternity care in Korea.

Objectives: This study identified the relationship between effectiveness of adequate prenatal care, accessibility of labor facilities, and timing of off-hours delivery as quality factors, and individual, obstetric, and provision factors, and severe maternal morbidity. In addition, this analysis estimated whether severe maternal morbidity was associated with postpartum hospital readmission, adjusting for all quality, individual, obstetric, and ii provision factors.

Methods: Data were extracted from the Korean National Health Insurance Service-National Sample Cohort for 91,767 cases of delivery that were delivered during 2003–2013. Severe maternal morbidity status was determined using the Center for Disease Control and Prevention’s algorithm including the diagnosis and procedure code during delivery hospitalization. Postpartum readmission rates within 6 weeks after delivery were determined. A generalized estimating equation (GEE) model with logit link was performed for the relationship with severe maternal morbidity and women’s factors to estimate adjusted odds ratios. Cox proportional hazards models with robust variancecovariance matrixes to account for repeated measures of individuals were used for the postpartum readmission and severe maternal morbidity to calculate adjusted hazard ratios.

Results: Of the 91,767 delivery cases, 2,248 (2.45%) had severe maternal morbidity. In the GEE model, severe maternal morbidity was higher in women who had inadequate prenatal care than in those who had adequate prenatal care (odds ratio (OR) 1.39, 95% CI 1.08-1.79), women who had weekday nighttime or weekend delivery had a higher risk of severe maternal morbidity compared with those who had weekday daytime delivery (OR 1.18, 95% CI 1.02-1.38, and OR 1.70, 95% CI 1.37-2.11, respectively). Access to labor facilities was not a statistically significant predictor. For maternal age, women who delivered at extremely young or old ages had high risks of severe maternal morbidity, which showed a J-shaped distribution through the whole age range. Women who had the lowest level of income, who had cesarean section delivery, who were nulliparous, who had twins or more than triplet births had high risks of severe maternal morbidity. In Cox analysis, women with severe maternal morbidity had higher risks of postpartum readmission than those without severe maternal morbidity (hazard ratio (HR) 2.29, 95% CI 1.70-3.10). Conclusion: Inadequate prenatal care delivery was associated with the occurrence of severe maternal morbidity during delivery hospitalization. In addition, weekday nighttime or weekend delivery was related to the risk of severe maternal morbidity. Moreover, women with severe maternal morbidity had higher risks of postpartum readmission. Therefore, policy makers should consider making quality indicators for timely, adequate, and sufficient visits during pregnancy and should monitor adequacy of prenatal care to prevent severe maternal morbidity and to improve maternal quality of health care; additionally, they should provide financial support and systematically allocate adequate human resources and labor facilities in vulnerable areas, as well as during weekends and night times to improve the quality of intrapartum and postpartum maternity care.