Not only are they the smallest among us, but premature children also face health and life challenges that make them the most vulnerable. Generally speaking, they have a slightly higher risk of mortality due to illness. It is now apparent that they also have a higher risk of unexpected death from so-called external causes: road traffic accidents, substance abuse and suicide.

These findings have been revealed in a major Nordic study led by Professor Kari Risnes from the Faculty of Medicine and Health Sciences at the Norwegian University of Science and Technology (NTNU). The researchers have analyzed birth data and causes of death for nearly 37,000 individuals aged between 15 and 50 who were born prematurely in Norway, Sweden, Denmark and Finland.

One finding in particular surprised them.

Higher risk of suicide for women born prematurely

The study reveals that prematurely born women have a nearly 80% higher risk of committing suicide compared to individuals born at full term. The researchers find no such elevated suicide risk in prematurely born men. Women born 7–17 weeks prematurely are actually almost as likely to commit suicide as men in the general statistics.

Suicide is a serious problem in society. The majority of suicides are committed by men, and it is the leading cause of death among young men in Norway, Europe and around the world.

“We don’t know why premature women now turn out to be at almost the same level,” said Risnes, who is an expert in pediatric epidemiology at the Department of Clinical and Molecular Medicine.

“What we do know is that both men and women born prematurely are more vulnerable to certain diseases. Some struggle mentally and socially, and experience other challenges as well,” said Risnes.

She also leads the NTNU life-course research group, which conducts population-based research on vulnerable children and young people.

Although many individuals who are born prematurely do very, very well, the pediatrician and researcher describes these vulnerabilities as extra baggage that they carry with them throughout their lives.

Associate Professor Signe Oppdal at the Department of Public Health and Nursing has led the analysis work and is the lead author of the article on premature birth and mortality recently. published in the journal BMC Medicine,

Confirmation that premature babies are more vulnerable

A full-term pregnancy lasts 40 weeks, and babies born before week 37 are considered premature. Today, the vast majority of premature babies survive. Even among babies born before week 28 of pregnancy—more than three months premature—survival rates exceed 80%. That is far more than just a few decades ago.

“Survival rates have really increased, but some people born prematurely require more follow-up, and they need everyone around them to understand that they might experience challenges,” said Risnes.

Risnes has also led previous studies from the four Nordic countries. Research shows that premature children have a higher mortality rate as young adults compared with people born at term. They are more vulnerable to heart disease, chronic pulmonary diseases and diabetes than the general population. Other studies have shown that people born prematurely have an elevated risk of mental disorders. Among other things, this may be linked to lower cognitive functions.

Investigating correlations

Children and young people generally have a low risk of dying. It is the sudden, violent deaths from road traffic accidents, suicide and substance abuse that claim the most young lives—even though all of these are theoretically preventable. These external causes of death are three times higher in men than in women—and they explain much of the excess mortality found among young men.

The researchers set out to study whether and how the vulnerabilities of prematurely born individuals potentially manifested in these external causes of death.

As early as 2017, the researchers had data from Norway that pointed towards an elevated risk of suicide. In addition to the risk of suicide, the team wanted to see whether prematurely born individuals are especially vulnerable to external, unnatural deaths such as road traffic accidents and substance abuse.

In addition, they wanted to investigate whether there are differences between the sexes.

So far, little research has been done on this topic. However, the Nordic research team has now shown that there is a correlation between premature birth and the risk of unexpected death. They have also shown that prematurely born women are just as vulnerable as men when it comes to suicide.

“The day we saw these girls right up here at the top of the graphs together with the boys, I must say, we were very surprised. Our first thought was to check whether we had made a mistake or overlooked something. We checked and double checked to make sure, so we are confident the findings are reliable. There is a very good research team behind this study, and we find the same pattern in all four countries,” said Risnes.

The big question now is whether there is something specific about prematurely born girls that makes them especially vulnerable.

“We really know very little about this. It is a small and very special group. We also don’t know if this is just the tip of the iceberg. We feel compelled to delve deeper,” said the NTNU professor.

She points out that there is quite a large group of premature babies who struggle when growing up. These children still, and often to a large extent, fall under the radar of the health care system, schools, and kindergartens.

Surprises from the Danes

When it comes to unnatural deaths, there are differences among the Nordic countries. This is something that has also been seen in other studies. The new study shows that particularly young Swedish women who were born prematurely are at high risk of committing suicide, at approximately the same rate as men.

In Denmark, however, the death rate from suicide among people born prematurely is much lower than in the other Nordic countries—Danish men are actually at the same level as Swedish, Finnish and Norwegian women. The Danes also have a much lower rate of death from substance abuse than their Nordic neighbors. The study shows that prematurely born men in Finland are particularly vulnerable to fatal road traffic accidents and deaths related to substance abuse.

Researcher and doctor—a fine balance

Risnes believes the strength of the study is that they have comparable data from four countries. She emphasizes that today’s neonatal care is very different from when the oldest participants in the study were born at the end of the 1960s.

The health care system is becoming increasingly successful at saving more and more premature babies.

At the same time, research is making us more aware of the increasing challenges faced by this group. Risnes is a pediatrician and an expert on premature babies, but she is also a researcher exploring the vulnerabilities and risks associated with being born too early—it can be a fine balance.

“Some people might see our research as labeling an entire group, which could cause concern. That said, we also note that patients and relatives want more knowledge. They want the people around them, such as kindergartens, schools, and the health care system. , to understand and provide the support they need.

“Perhaps we as researchers can also help highlight that we all have strengths and vulnerabilities. In this way, we can contribute to society better understanding and accepting that people are different,” she said.

Identifying correlations and mitigating challenges

Premature birth is a risk factor that follows 6% of the population throughout life. To mitigate the challenges they face, the researchers hope to investigate the latest findings more thoroughly.

When asked about the difference she hopes their research can make, Risnes highlights that it could be used for a much-needed update of the guidelines for the follow-up of premature infants (report in Norwegian). The current guidelines are from 2007 and only apply to children up to the age of 5 years. For many people, it is only then that the challenges begin.

“That is when children start school, and it is precisely then that parents feel they need support the most,” said Risnes.