The Apgar score pediatricians use to evaluate a baby's condition at birth could also help predict whether a mother will need to be admitted to intensive care, a Canadian study suggests.

More than 50 years ago, pediatrician Virginia Apgar developed a score that doctors, midwives and nurses used to assess whether newborns need immediate medical care based on the baby's colour, heart rate, reflexes, muscle tone and respiration in the first few minutes after birth. 

Currently, health-care providers consider factors such as a mother's blood pressure, oxygen level and blood loss at birth to measure how ill she is. In both high-resource and low-resource settings, these traditional indicators are probably not great for recognizing a sick mom, said study author Dr. Joel Ray, a physician and researcher at St. Michael's Hospital in Toronto.

Newborn

The Apgar score is used to assess whether newborns need immediate medical care based on the baby's colour, heart rate, reflexes, muscle tone and respiration in the first few minutes after birth. (CBC)

That's why the researchers hope the extra information from the newborn Apgar score could improve their ability to detect a woman who is severely ill or is at risk of becoming so ill within hours of childbirth.  

The risk of death for newborns and their mothers is highest when both are admitted to the intensive care unit (ICU) after delivery, Ray previously found.

Now the team has built on that observation by examining the health records of more than 600,000 single babies born in Ontario between 2006 and 2012.

"A low five-minute newborn Apgar score reflects a higher risk of maternal ICU, with and without mechanical ventilation," the researchers said in a research letter published in Monday's issue of the journal JAMA Pediatrics.

Sometimes the mother's need for critical care can be judged by looking at her alone. But not always, and that's where the baby's Apgar score can be useful.

"Because of the nature of a birth, there are a lot of things going on, including dealing with the newborn, and the excitement of the delivery itself," Ray said in an email. "Such things might distract us from realizing that the mother is more ill than she seems. This is especially so because a young and previously healthy women might have a lot of physical reserve, in which classic maternal vital signs do not appear that bad after birth, but decline only once the mother is ill."

The study's findings included:

  • Among mothers whose baby had a normal Apgar score five minutes after birth, 1.7 per 1,000 of the women were admitted to an ICU.
  • When the Apgar score fell into the intermediate range, 12.3 of every 1,000 mothers were admitted to an ICU.
  • When the newborn's Apgar score was in the low range, the mother's rate of ICU admission rose to 18.2 per 1,000.

The researchers took into account the mother's age, number of previous deliveries, income level and whether she had certain chronic health conditions such as diabetes before pregnancy.

"Our study shows that a universally available metric for newborns — the Apgar score — provides a promising and novel application for mothers as well,"  Ray, who is also an adjunct scientist at the Institute for Clinical Evaluative Sciences, said in a release. "At a minimum, it confirms that, even after birth, the health of the baby and mother remain intimately linked."

He speculated the effect probably lasts a matter of hours up to about one day.

The research was funded by the Canadian Institutes of Health Research. 

With files from CBC's Amina Zafar