Researchers trying to predict premature births

Second study will determine if extremely low-birth-weight preemies age faster as adults

Predicting premature labour and preventing it before it starts is the focus of a McMaster University study.

The importance of identifying pregnant women most at risk is evident in a second study looking at potential serious health effects of being born too early.

It will determine if extremely low-birthweight preemies age faster as adults.

Both studies are among 25 in Canada receiving a total of $1.85 million from the Canadian Institutes of Health Research (CIHR) to spend a year finding ways to improve health outcomes for babies and moms.

“I think it is a really important time in Canada for preterm birth research,” said Dr. Sarah McDonald, high-risk obstetrician at Hamilton Health Sciences and professor of obstetrics and gynecology at McMaster. “I think we are on the cusp of making some really big changes that will help to decrease our preterm birth rate.”

McDonald’s study will comb through thousands of Ontario births — about six per cent of births are premature when twins or other multiples are excluded — looking for factors during pregnancy, in the mother’s medical history or during her other births that could flag those most at risk.

The ultimate goal is to develop tools to help doctors and midwives predict which women are more likely to have preemies.

“The ideal first step would be prevention,” said McDonald. “The second step if we can’t prevent preterm birth, can we prevent some of the conditions that go with preterm birth?”

For the women, it would mean having the most appropriate caregiver from the outset, giving birth in a hospital best equipped to care for preemies, receiving preventative treatments to ward off early labour or strengthen a baby’s lungs and being better prepared to handle such a traumatic event.

“If we could understand better which women were at risk, we might be able to target care to those women in a different way and hopefully improve outcomes,” said McDonald.

Predicting early labour is the next piece in the puzzle after McDonald and a team of 20 international collaborators determined the best way to prevent it.

Their research published in April in international journal of obstetrics and gynecology BGOG concluded the hormone progesterone worked better than holding the cervix closed with an operation called cerclage or a rubber ring placed in the vagina called a pessary.

“The study was important because all three were being used to try to prevent preterm birth,” said McDonald. “The question that I and most high-risk obstetricians had was, ‘What is the best way?’”

Progesterone was found to half the odds of being born before 34 weeks of pregnancy and half the chance of preemies dying in a special type of meta-analysis that took two years to complete and was funded by CIHR.

McDonald says the tablet placed in the vagina once a day could prevent as many as one-third of preterm births.

“It’s a really effective method that seems to have no downsides to it,” she said. “If we can prevent it, it’s so much better than treating the outcome.”

One of those potential outcomes is premature aging as an adult.

Hamilton researchers working with what is believed to be the world’s longest studied cohort of extremely low-birth-weight preemies observed they look older than they should as adults and appear to be experiencing decline in cardiac physiology faster.

“The grant will provide us with an opportunity to answer the question of whether they are aging more quickly,” said Dr. Ryan Van Lieshout, assistant professor of psychiatry and behavioural neurosciences at McMaster. “If they are aging faster, it’s very important for them and their physicians to be aware.”

The study will examine 100 preemies weighing less than 1,000 grams when born in Hamilton between 1977 and 1982 and compare them to 89 of their peers born at term.

Researchers will not only look at whether their aging is accelerated but why to determine if there are ways to slow or prevent it.

“More of these babies are being born than ever before and because of advances in technology more of them are surviving than ever before,” said Van Lieshout. “We really want to do this work so we can help them be as healthy as possible as they get older … We’re really hoping to identify things that are reversible or things that we can intervene on to help them age in as healthy way as possible.”