NEW YORK (Reuters Health) – The prevalence of obstetric complications resulting in severe maternal morbidity — particularly pulmonary embolism and need for blood transfusions — increased significantly in the US between 1998 and 2005, investigators report in the February issue of Obstetrics and Gynecology.

During the same period, rates of cesarean delivery rose from 21.1% to 31.1%, Dr. Susan F. Meikle, at the National Institutes of Health in Bethesda, Maryland, and co-authors note. The proportion of delivery hospitalizations involving older women and women on Medicaid/Medicare also increased with time, as did deliveries characterized by multiple births, hypertension, diabetes, and cesarean delivery.

However, they point out, “comprehensive population-based information on severe obstetric complications remains very limited.”

To examine trends in severe labor and delivery complications, the authors used data from the Nationwide Inpatient Sample of the Healthcare Cost and Utilization Project for more than 32 million delivery discharge records.

The proportion of deliveries with at least one severe obstetric complication increased from 0.64% in 1998-1999 to 0.81% in 2004-2005, the report indicates.

There was a 52% increase in pulmonary embolism and a 92% increase in blood transfusions. Rates of renal failure, respiratory distress syndrome, shock, and mechanical ventilation increased by about 20%.

By contrast, rates of severe complications of anesthesia declined, and there was no significant change in heart failure, puerperal cerebrovascular disorders, pulmonary edema, deep venous thrombosis, disseminated intravascular coagulation, and sepsis.

Adjustment for cesarean delivery explained almost all the increases in estimated risk of renal failure, respiratory distress, and ventilation, although the authors note that their results “do not demonstrate causality.”

Dr. Meikle’s team points out that the UK has established a surveillance system for rare obstetric complications. Development of a similar system in the US “may improve the ascertainment, monitoring, and classification of these complications and potentially identify modifiable risk factors.”

Reference:
Obstet Gynecol 2009;113:293-299.