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Stress increases stillbirth risk
PUNCHSTOCK
This week–
Don’t stress me out, I’m pregnant NORA SCHULTZ
IF YOU are pregnant, think twice before taking on an extra project at work. Severe stress, even in the short term, may almost double the risk of having a stillbirth – although stillbirths are rare. Stress has been linked to premature birth, high blood pressure and other health problems associated with stillbirths. Now Kirsten Wisborg from the Aarhus University Hospital in Denmark and colleagues have shown that stress increases the risk even when women don’t have these problems. “We don’t yet know for sure whether stress may directly cause stillbirth, but our results are enough for doctors and midwives to be concerned,” she says. The researchers analysed questionnaires filled in by over 19,000 women during the last three months of pregnancy. In one section, the survey asked them whether they were unable to concentrate or handle problems, had lost self-confidence or felt unhappy or unworthy, compared to just a few weeks before. Based
Telltale DNA leaves its mark in household dust MURDERERS and thieves beware. Human DNA has been identified in household dust for the first time. The amount of DNA in dust is tiny and from so many people that singling out any individual could be tricky. With further research it might be possible to find ways of recreating someone’s profile or even working out how recently they’d visited a crime scene from the decay of their DNA. 16 | NewScientist | 31 May 2008
on their answers, a third of the women scored highly for stress. The researchers then monitored how many women had stillbirths. They found that in the highstress group, 29 of the women – or 0.5 per cent – had stillbirths after 28 weeks, whereas in both the intermediate and low-stress groups, it was about 0.3 per cent (BJOG, DOI: 10.1111/j.14710528.2008.01734.x). The results held up even when women with high blood pressure, premature delivery or other relevant health problems were excluded from the analysis. Although the figures are small, Wisborg says that difference is significant: “Thankfully, stillbirth is a rare event. But we still do not know what causes it and any clues we find can help us reduce the risks.” Studies in monkeys suggest that stress hormones such as adrenalin might be reducing blood flow to the placenta, which could restrict oxygen supply to the fetus. Although the effect is likely to be small, if the baby has any other problems, stress could “tip the balance”, says Andrew Shennan, an obstetrician
The discovery that human DNA is detectable and measurable in dust is a first, say researchers who report their findings in Forensic Science International (DOI: 10.1016/ j.forsciint.2008.01.016). “People have quantified the amount of DNA in dust many times before, but no one had looked before for human DNA,” says Bonnie Brown, co-leader of the team at Virginia Commonwealth University in Richmond. The team collected dust samples from various rooms around their campus, from highly trafficked classrooms to quieter offices. Most of the DNA they recovered came from bacteria or fungi, but there was
–Stay calm, it’s only work–
at St Thomas’ Hospital in London and spokesman for baby charity Tommy’s. The next step, he says, is to reduce stress in pregnant women and see if that reduces stillbirths. But Vivette Glover, a perinatal psychobiologist at Imperial College London says that people should start changing their behaviour now. The stillbirth results are the latest in a growing list of ways that stress during pregnancy may harm babies,
which includes cognitive problems in children and miscarriage. “People looking after pregnant women should pay much more attention to their emotional health and employers should be open to flexible working hours,” says Glover. The current study only measured the effect of recent increases in stress. If chronic stress was taken into account, more of the stillbirths may have been linked to stress, says Wisborg. G
human DNA in all but one of their 36 samples. Though each sample contained just trillionths of a gram of DNA, it was enough for amplification and profiling via the DNA kits used in forensic labs. But the read-outs contained overlapping signals from so many people that it was virtually impossible to pick out any one person’s DNA profile. Adrian Linacre of the Centre for Forensic Science at the University of
Strathclyde in the UK says that as things stand, such evidence is of little forensic value. “Forensic investigators are already aware of background levels of DNA at crime scenes, and know when they’re not relevant to a case,” he says. The key is to connect DNA from a blood spot or hair to an event that took place. Most dust would have been left there by occupants of the room well before any event took place, Linacre says. Brown hopes that the forensic usefulness of dust will improve with more research to uncover how fast DNA accumulates and how soon it degrades. Andy Coghlan G
“There was human DNA in all but one of their 36 samples. Though just trillionths of a gram it was enough for profiling in a lab”
www.newscientist.com
This week–
Don’t stress me out, I’m pregnant NORA SCHULTZ
IF YOU are pregnant, think twice before taking on an extra project at work. Severe stress, even in the short term, may almost double the risk of having a stillbirth – although stillbirths are rare. Stress has been linked to premature birth, high blood pressure and other health problems associated with stillbirths. Now Kirsten Wisborg from the Aarhus University Hospital in Denmark and colleagues have shown that stress increases the risk even when women don’t have these problems. “We don’t yet know for sure whether stress may directly cause stillbirth, but our results are enough for doctors and midwives to be concerned,” she says. The researchers analysed questionnaires filled in by over 19,000 women during the last three months of pregnancy. In one section, the survey asked them whether they were unable to concentrate or handle problems, had lost self-confidence or felt unhappy or unworthy, compared to just a few weeks before. Based
Telltale DNA leaves its mark in household dust MURDERERS and thieves beware. Human DNA has been identified in household dust for the first time. The amount of DNA in dust is tiny and from so many people that singling out any individual could be tricky. With further research it might be possible to find ways of recreating someone’s profile or even working out how recently they’d visited a crime scene from the decay of their DNA. 16 | NewScientist | 31 May 2008
on their answers, a third of the women scored highly for stress. The researchers then monitored how many women had stillbirths. They found that in the highstress group, 29 of the women – or 0.5 per cent – had stillbirths after 28 weeks, whereas in both the intermediate and low-stress groups, it was about 0.3 per cent (BJOG, DOI: 10.1111/j.14710528.2008.01734.x). The results held up even when women with high blood pressure, premature delivery or other relevant health problems were excluded from the analysis. Although the figures are small, Wisborg says that difference is significant: “Thankfully, stillbirth is a rare event. But we still do not know what causes it and any clues we find can help us reduce the risks.” Studies in monkeys suggest that stress hormones such as adrenalin might be reducing blood flow to the placenta, which could restrict oxygen supply to the fetus. Although the effect is likely to be small, if the baby has any other problems, stress could “tip the balance”, says Andrew Shennan, an obstetrician
The discovery that human DNA is detectable and measurable in dust is a first, say researchers who report their findings in Forensic Science International (DOI: 10.1016/ j.forsciint.2008.01.016). “People have quantified the amount of DNA in dust many times before, but no one had looked before for human DNA,” says Bonnie Brown, co-leader of the team at Virginia Commonwealth University in Richmond. The team collected dust samples from various rooms around their campus, from highly trafficked classrooms to quieter offices. Most of the DNA they recovered came from bacteria or fungi, but there was
–Stay calm, it’s only work–
at St Thomas’ Hospital in London and spokesman for baby charity Tommy’s. The next step, he says, is to reduce stress in pregnant women and see if that reduces stillbirths. But Vivette Glover, a perinatal psychobiologist at Imperial College London says that people should start changing their behaviour now. The stillbirth results are the latest in a growing list of ways that stress during pregnancy may harm babies,
which includes cognitive problems in children and miscarriage. “People looking after pregnant women should pay much more attention to their emotional health and employers should be open to flexible working hours,” says Glover. The current study only measured the effect of recent increases in stress. If chronic stress was taken into account, more of the stillbirths may have been linked to stress, says Wisborg. G
human DNA in all but one of their 36 samples. Though each sample contained just trillionths of a gram of DNA, it was enough for amplification and profiling via the DNA kits used in forensic labs. But the read-outs contained overlapping signals from so many people that it was virtually impossible to pick out any one person’s DNA profile. Adrian Linacre of the Centre for Forensic Science at the University of
Strathclyde in the UK says that as things stand, such evidence is of little forensic value. “Forensic investigators are already aware of background levels of DNA at crime scenes, and know when they’re not relevant to a case,” he says. The key is to connect DNA from a blood spot or hair to an event that took place. Most dust would have been left there by occupants of the room well before any event took place, Linacre says. Brown hopes that the forensic usefulness of dust will improve with more research to uncover how fast DNA accumulates and how soon it degrades. Andy Coghlan G
“There was human DNA in all but one of their 36 samples. Though just trillionths of a gram it was enough for profiling in a lab”
www.newscientist.com