Multiple factors influence survival of extremely premature infants

Multiple factors influence how well a severely premature infant (23 weeks gestation) will do after birth and over the long-term, according to researchers at Loyola University Chicago Stritch School of Medicine. These findings were published in the latest issue of the American Journal of Perinatology.

Researchers found that males, multiples and premature infants born in a hospital without a neonatal intensive care unit had a significantly higher death rate. Lack of exposure to steroids before birth and lower birth weights also significantly increased the risk for disability. Some studies suggested that babies born via c-section had survival advantages. African-American infants also had higher survival rates in certain studies, but conflicting evidence remains on the role of race and prognosis for these infants.

"The survival of extremely premature infants has improved considerably over the past three decades," said Jonathan Muraskas, MD, lead author, co-medical director, neonatal intensive care unit, Loyola University Health System, and professor, neonatology, Stritch. "Despite these survival rates, the number of infants born with severe or profound developmental disabilities remains high. This study sheds light on factors that may protect these infants."

These data come from a retrospective review over a 25-year period (1987 - 2011) of 87 successfully resuscitated infants at 23 weeks of pregnancy. Researchers studied the effects of poor prenatal care, race, gender, inflammation of fetal membranes, steroid use during pregnancy, delivery route and location, Apgar score, birth weight and multiple births on short and long-term outcomes.

Forty-three percent of the infants in the study did not survive. Eighty-eight percent of the survivors were evaluated at 2 years of age with 66 percent diagnosed with moderate-to-severe neurological impairment.

"There is no consensus on early treatment strategies that can accurately predict survival and profound developmental impairments based on observations in the first 48 hours of life," study authors noted. "Infants born 16 - 17 weeks early can survive, but may have cerebral palsy, blindness and deafness and may require significant resources for the rest of their life. This study will help to identify those infants at risk and help us guide how we care for them."