Despite the untimely loss of their daughter, Neil and Morven Cattigan haven't given up; instead, they're pushing for more public education.

"In the 14 months since our cherished daughter's passing, we are still no further forward in seeking answers from Scottish Rugby about the events which led to Siobhan's tragic and avoidable passing," the parents of Siobhan Cattigan said late last month. The Scotland rugby international died suddenly in November 2021, aged just 26.

Her parents attribute Siobhan's death to two concussions she sustained while playing for Scotland in February 2020 and March 2021. After that, their daughter's personality radically changed, almost like dementia, Morven Cattigan told The Sunday Times.

"Siobhan was crumbling before our eyes; something catastrophic had happened in her brain," she said. 

The family has launched legal action against World Rugby and Scottish Rugby, the international and national governing bodies. They believe that Cattigan did not receive adequate care for her injuries. 

Scientific studies have shown that female athletes need more time than male athletes to recover from head injuries such as concussions. Other studies suggest that women in contact sports such as rugby, American football and even soccer are also at a higher risk of sustaining a head injury than men.

A study carried out between 2000 and 2014 by researchers at Columbia University in New York revealed a 50% higher rate of concussions among women than men. Data collected from 80,000 female and male high school soccer players in the state of Michigan between 2016 and 2019 found that young female players were at twice the risk of their male counterparts.

Weaker neck muscles  

Researchers believe one reason for this possible greater susceptibility to head injuries is the neck muscles, which are less developed in women. 

"If there is less muscle mass to act as a stabilizer, there is faster and stronger movement of the head and it takes longer to stabilize," Inga Körte, professor of neurobiology at Ludwig Maximilian University in Munich and Harvard Medical School in Boston, told DW. 

"During this time, the brain flies forward and backward in the skull, so to speak. This results in a higher mechanical load on the brain and thus probably a higher risk of it getting injured." 

Hormonal structure a factor?

Professor Körte has spent years studying head injuries in sports, including the question of whether the female hormonal structure makes women's brains more vulnerable. She's also studying the possible roles of the menstrual cycle and hormonal contraceptives such as IUDs or the pill. 

Another possible reason that female athletes are at higher risk is the fact that women's axons – tubular projections of nerve cells – are thinner and made up of fewer microtubes than those of men. 

"Imagine male axons being like a 10-lane highway, females like a dual carriageway, so if there's an accident in one of the lanes, males have more lanes to accommodate the traffic, whereas females may experience more delays and traffic jams," Elisabeth Williams of Swansea University in Wales told DW.

Her area of research is head injuries in contact sports, particularly in female rugby players. In addition to physical factors, Williams points to sociological aspects that may also make female athletes more likely to suffer head injuries than men. 

"A lot of female rugby players, who I mainly work with, didn't have access to rugby through school, so only started playing at university," Williams notes. "They've missed out on years of age and stage-appropriate training, coaching, falling techniques, specific strength [in the] neck and upper body." 

'Education, education, education'

Therefore, she says, such athletes have a lot of catching up to do and demands "Education, education, education for players, coaches, parents and support people about the differences in symptoms that females may present with following a brain injury, the biomechanical/hormonal aspects mentioned, and longer recovery times."

The fact that women take longer than men to recover from concussions is supported by numerous studies, said Inga Körte. 

"They also have a higher risk of chronic symptoms — not only headaches, but also psychosocial issues that may not be associated with concussion later on."  

So, are female athletes also at a higher risk of neurodegenerative diseases such as CTE (chronic traumatic encephalopathy, also known as boxer's syndrome), Alzheimer's disease or other forms of dementia as a result of head injuries sustained in competition? 

"Women are more likely to develop dementia than men to begin with," Körte said, adding that the theory that female athletes who have suffered head injuries in their careers are at an even higher risk is yet to be proven. 

"But it is driving three of my major research projects," Korte said. "It is possible." 

The danger of 'appeasement activism' 

The scientist warns against what she describes as "appeasement activism," citing some relatively recent rule changes. 

"The danger is that you could wind up relying on a new rule that unfortunately doesn't get to the heart of the matter," she said, referring to a US rule that bans training headers for children under the age of 10. 

"There is no data to show that everything is fine from the age of 11; quite the opposite," Körte stressed. "Fourteen and 15-year-olds head the ball very frequently and they are in the midst of puberty, the maximum hormonal surge. Their brains are probably the most vulnerable of all."

Research into the possible higher risk of head injuries in female athletes remains in its infancy, Körtes cautioned, noting that 80% of participants in studies on concussions in sports have been male. 

However, this is slowly changing. A long-term US study is exploring the link between severe head injuries in football and American football and the possible later onset of CTE or other neurodegenerative diseases. Female former players over the age of 40 are among those taking part, including World Cup winners like Brandi Chastain, Michelle Akers and Shannon MacMillan. 

However, for Scotland rugby player Siobhan Cattigan, this comes far too late, leaving her father Neil with a bitter truth.

"They fixed her broken bones but turned their backs on Siobhan's broken brain."

This article was translated from German.