A mother’s fever, not its cause, can lead to heart and facial defects such as a cleft palate in her baby, a new study finds.
It has been known for decades respiratory illnesses in expectant mothers increase the danger of a range of health problems in the unborn baby, including facial deformities.
But the cause has remained a mystery with debate over whether it is a virus, another infection or the fever alone that damages the fetus.
Now, new research by Duke University in Durham, North Carolina provides the first evidence it is the fever itself, and not its root source.
If a pregnant woman develops a fever early in her pregnancy, it could cause birth defects such as heart problems and cleft palate in her baby
The cells that build are involved in building a fetus’s heart, face and jaw are temperature sensitive.
A fever during the first three to eight weeks of pregnancy can interfere with the development of these parts of the baby, said the research team.
Neonatologist Professor Eric Benner advised mothers to be to take acetaminophen if they are feeling sick or feverish.
The results, published in Science Signaling, were demonstrated in animal embryos, but apply to humans.
Dr Brenner said that acetaminophen ‘has been studied extensively and determined to be safe during the first trimester.’
‘While doctors advise most women to avoid any drug during pregnancy, there may be benefits to taking acetaminophen to reduce fever.’
Dr Benner said nonsteroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen and aspirin also reduce fevers, but some are not safe to use during the later stages of pregnancy.
There is also ongoing debate over whether sustained use of acetaminophen is safe during pregnancy to manage ongoing conditions such as arthritis, he said. But Dr Brenner says that using the medication on occasion for an acute problem does not pose such a risk.
‘These findings suggest we can reduce the risk of birth defects that otherwise could lead to serious health complications requiring surgery.’
Acetaminophen is generally not considered an NSAID because it has only little anti-inflammatory activity.
To observe how fever impacts a developing fetus, the researchers studied zebra fish and chicken embryos.
A mother’s fever itself, not the underlying cause, during early pregnancy can cause birth defects such as cleft palate in her child, a new Duke University study finds
Dr Benner and his team found that neural crest cells, which are the building blocks of the heart, jaw and face, ‘contain temperature-sensitive ion channels that typically are found in your sensory neurons.
‘They’re the channels that, when you stick your hand in a hot cup of water, tell your body the temperature has changed.’
His researchers engineered a non-invasive magnet-based technology to create fever like conditions in two specific temperature-sensitive ion channels called TRPV1 and TRPV4 in the neural crest cells involved in developing the heart and face.
When those were subjected to conditions mimicking a temporary fever, the embryos developed skull and face abnormalities, and heart defects.
The type depends on whether the fever occurs during the development of the heart, or head and face.
What researchers still do not know is whether the severity or duration of a fever affects development, Dr Benner said.
He said: ‘We have known since the early 1980s fevers are associated with birth defects, but how that was happening has been a complete mystery.’
It is challenging to gather data from mothers on the circumstances, severity or duration of a fever from many months before, he said.
‘I hope moving forward, we can educate more women about fever as a risk factor for birth defects and let them know they shouldn’t just tough it out if they develop a fever.’