Foetuses that are either too small or too large are at increased risk for stillbirth, a large new study says.
Researchers analysed all the stillbirths that occurred over 2.5 years at 59 hospitals in five regions of the United States. They found that abnormal foetal growth was associated with between 25% and 50% of the stillbirths.
Stillbirth refers to a foetal death that occurs during pregnancy at 20 weeks' gestation or later, according to the American College of Obstetricians and Gynaecologists.
Strategies to prevent stillbirth
The news study found that foetuses that were small for gestational age had a threefold to fourfold higher risk of stillbirth compared to those with normal weight. Being large for gestational weight was also associated with a greater likelihood of stillbirth.
The findings suggest that strategies to prevent stillbirth should focus on identifying foetuses that are small or large for gestational age, according to a journal news release.
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This is not part of current practice, noted study author Radek Bukowski and colleagues from the US National Institute of Child Health and Human Development-funded Stillbirth Collaborative Research Network.
They said that classifying the 10% of foetuses at the extreme ends of being too large or small as being abnormal could identify as many as 46% of future stillbirths.
While the study found an association between abnormal foetal size and risk of stillbirth, it did not establish a cause-and-effect relationship. Some aspects of the study's design could affect accuracy, the news release noted.
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