Corticosteroid use by women at risk of imminent preterm birth is associated with an increased risk of the child developing psychological developmental and neurosensory disorders. A researcher says that the risks and benefits to pregnant women should be carefully considered before using corticosteroids.
Millions of pregnant women worldwide who are at high risk of going into labour prematurely use corticosteroids. The drugs have been a game-changer, since they substantially increase the probability that the child will survive when the mother is at high risk of going into labour before week 32 of pregnancy. There is also broad scientific consensus that women who risk giving birth prematurely up to 34 weeks and 0 days should use corticosteroids.
However, a new study shows that there are risks associated with using corticosteroids.
A study of health data in Finland shows that children whose mothers have used corticosteroids during pregnancy have an increased incidence of psychological developmental and neurosensory disorders.
A researcher behind the study says that the results call for caution in using corticosteroids during pregnancy.
“When women are at risk of going into labour before 34 weeks and 0 days of pregnancy, they should still use corticosteroids, because the benefits for the child clearly outweigh the associated risks. However, there is talk of also using corticosteroids more frequently among women who are at risk of giving birth in weeks 34–37 of pregnancy, because many of the children develop lung problems. These women can use corticosteroids, but the psychological developmental and neurosensory disorders last forever. Doctors should err on the side of caution and should only give corticosteroids to women in this group when really necessary,” explains Eero Kajantie, Research Manager, Finnish Institute for Health and Welfare.
The research has been published in JAMA Network Open.
Data for 670,000 children
Corticosteroids help unborn children to progress rapidly through the last stages of fetal development and especially prepare the lungs for life outside the womb.
This is why using corticosteroids is standard, since premature babies otherwise risk dying because they cannot breathe.
However, corticosteroids affect all cells in the body and can therefore potentially also affect cells in the brain and central nervous system.
The researchers used data from various nationwide registries in Finland to investigate the incidence of psychological developmental and neurosensory disorders among children whose mothers used corticosteroids during pregnancy and a control group of children whose mothers did not use corticosteroids during pregnancy.
The psychological developmental disorders included developmental disorders of speech and language, of motor function and of scholastic skills and other unspecified disorders of psychological development. The neurosensory disorders included loss of vision or hearing, cerebral palsy and epilepsy.
The researchers had data for 670,097 children, of which 14,868 had been exposed to corticosteroids prenatally. Of these, 6,730 were born at term and 8,138 prematurely.
Of the 655,229 children whose mothers did not use corticosteroids, 634,757 were born at term and 20,472 prematurely.
The researchers also had data on 241,621 siblings, of whom 4,128 had not been exposed to corticosteroids, even though one sibling had been.
“A separate finding is that almost half the women at risk of imminent preterm birth who used corticosteroids ended up giving birth at term. This shows that using corticosteroids does not always benefit their children. However, predicting who actually will end up giving birth prematurely is difficult,” says Eero Kajantie.
Corticosteroids associated with increased risk of various disorders
The results show that exposure to corticosteroids before birth is associated with a 30–40% increased risk of a child developing the psychological developmental and neurosensory disorders mentioned previously.
Eero Kajantie says that since the risk of developing the individual disorders is so small that women at imminent risk of preterm birth who use corticosteroids should not be concerned at the individual level. However, there is cause for concern at the population level, since many children’s psychological developmental and neurosensory disorders could be associated with exposure to corticosteroids in the later stages of fetal development.
“We cannot say that corticosteroids caused any specific child to develop any psychological developmental and neurosensory disorders, but we can show that deeper understanding of these associations is worth exploring,” he adds.
Caution in using corticosteroids
The researchers adjusted their data for birth weight, the fetal stage at which corticosteroids were used and other factors, but the results remained unchanged.
This also applied to the unexposed siblings of the children exposed to corticosteroids prenatally, who did not have the same risk of developing the disorders as those exposed.
Eero Kajantie says that the study is not surprising, since it confirms what the same researchers found 2 years ago in another study. However, in the new study, the researchers examined the risks associated with the specific psychological developmental and neurosensory disorders in greater detail.
He therefore also thinks that the results should emphasise concern about women at risk of imminent preterm birth using corticosteroids and the extent of use.
Eero Kajantie elaborates that women who risk going into labour before 34 weeks and 0 days of pregnancy should still use corticosteroids because the benefits clearly outweigh the risks.
Nevertheless, he thinks that doctors today have very good potential to successfully overcome the lung problems among children born prematurely, so that women who risk premature birth later than week 34 in pregnancy probably take unnecessary risks by using corticosteroids.
“Babies born after week 35 of pregnancy usually do very well anyway. They may have respiratory problems, but these are easy to treat and manageable. The potential benefits of using corticosteroids may not sufficient to outweigh the associated risks. I therefore think that we should be very careful about recommending that women use corticosteroids late in pregnancy,” explains Eero Kajantie.
He also emphasises that the relevant guidelines are updated regularly, so obstetricians already know about the potential risk.
“Obstetricians are aware of the risk, and they also know that determining which women could benefit from corticosteroids and which women should avoid using them can be difficult,” concludes Eero Kajantie.