Dartmouth study finds NICU admission rates are increasing for newborns of all weights

Neonatal intensive care units were originally created for newborns who are extremely ill and/or underweight, but a Dartmouth study finds that NICU admission rates are increasing for newborns of all weights. In effect, NICUs are increasingly caring for normal, or near normal, birth weight and term infants.

The findings, which appear in the journal JAMA Pediatrics, raise questions about possible overuse of this highly specialized and expensive care for some newborns. A PDF is available on request. The study was conducted by Wade Harrison, MPH, and David Goodman, MD, MS, of The Dartmouth Institute for Health Policy and Clinical Practice.

Since 1960, when the first NICU was established in the United States, the neonatal mortality rate has fallen more than four-fold -- from 18.73 per 1,000 live births to 4.04 per 1,000 live births (in 2012). While much of the decline can be attributed to the highly specialized care premature and sick infants receive in NICUs, there have been few studies that looked beyond very-low birth weight infants admitted to NICUs to examine how neonatal care relates more broadly to overall newborn care.

Thanks to a 2003 revision to the U.S. Standard Certificate of Live Birth, which included a new field to indicate whether a newborn was admitted to the NICU, Harrison and Goodman were able to examine data for nearly 18 million live births to U.S. residents from January 2007 through December 2012 in 38 states and the District of Columbia. Using this population-based data, they demonstrated that NICU admissions have increased steadily from 2007 to 2012. Even adjusting for characteristics likely to influence a newborn's chance for NICU admission, the rates still show a relative increase of 23 percent during the six years of the study. Additionally, the study found that by 2012 nearly half of all NICU admissions were for normal birth weight infants or for those born at 37 weeks gestation or older.

The fact that admissions are increasing for normal or near-normal birth weight babies doesn't indicate anything about the necessity of those admissions. But it does raise questions worth examining in the future, Harrison and Goodman note. "Some people might ask how more care could ever be a problem for a baby," Goodman says. "But a NICU admission has risks and consequences for newborn and their families. There may be opportunities to provide great care in less intensive settings."

In addition to the high cost of NICU care, there is the potential for increased exposure to invasive medical tests and procedures as well as increased stress for both the newborn and the family. "The first few days are a critical time in a child's life, and it's a critical bonding time for the baby and the new parents," Harrison says. "Spending time in a NICU is not the same as time spent at home or in a birthing pavilion. It's very stressful for both the infant and the family."

Harrison and Goodman plan to conduct additional studies related to NICU care, particularly the extent to which care varies across regions and hospitals.