Taking the guess work out of estimating birth weights

The results of a new study may help doctors better estimate the birth weight of newborns. Since a baby’s weight and size are directly related to its health, the new information will help physicians and parents make better decisions concerning care, researchers say.

Study leaders at Michigan State University devised a new way of analyzing national birth records adjusting for implausible birth weight estimates to reach their conclusions. The findings were published in the journal Pediatrics.

“More than 7 million records were reviewed,” said study co-leader, Nicole Talge, in a news release. “Our research looked at live births in the United States during 2009-2010 and using a newly developed method, corrected unlikely gestational ages during that time. This led to changes in the birth weight thresholds, especially for preterm and post-term babies.”

These thresholds are critically important because they determine whether the baby is big or small for its gestational age, Talge said.

Researchers looked in detail at the time between the mothers’ last menstrual period and compared the estimated weight against the actual weight to spot mistakes in estimates.

Some low birth weight babies may be at higher risks for problems, according to the Centers for Disease Control and Prevention.  They may become ill in the first days of life or develop infections. Others may suffer from longer-term problems such as delayed motor and social development or learning disabilities.

The study members said they hope the new, more precise method will lead to healthier births and beyond.

“It’s important to remember that birth size is only one piece of the puzzle when it comes to evaluating a baby’s health,” said Talge.