Kids who are born by pre-labour caesarean section delivery are at an increased risk of acute lymphoblastic leukaemia (ALL), a type of blood cancer characterised by an overproduction of immature white blood cells.
"Our goal was to determine if there was an association between caesarean deliveries and ALL, to identify potential new targets for research into cancer prevention if there is a correlation," said one of the lead researchers Erin Marcotte, assistant professor at University of Minnesota Medical School in the US.
‘While the link between overall caesarean delivery and childhood leukaemia was not statistically significant, it was notable to find an association between pre-labour caesarean delivery and acute lymphoblastic leukaemia (ALL).’
"While the link between overall caesarean delivery and childhood leukaemia was not statistically significant, it was notable to find an association between pre-labour caesarean delivery and ALL," Marcotte noted. A potential correlation between pre-labour caesarean delivery (PLCD) and acute lymphoblastic leukaemia could offer new targets for cancer prevention research.
The study was published in the journal The Lancet Haematology. The analysis looked at 33,571 participants overall, including 23,351 control participants and 8,655 cases of ALL. After looking most closely at deliveries where the reason for caesarean were available, the analysis showed a 23 percent increase in risk of ALL in children born by pre-labour caesarean delivery.
The reason for the increased risk of ALL with pre-labour caesarean section delivery is not known. Several mechanisms may be at play, including the stress response in the foetus caused by labour and the colonisation of microbiota a newborn experiences during a vaginal delivery that is missed during birth by a caesarean section.
"The most plausible explanation for the association between ALL and pre-labour delivery by caesarean section is in the cortisol, or stress-related mechanism," Marcotte said. "Because ALL is not associated with all caesarean deliveries, it seems less likely the microbiota colonisation is a significant factor in this phenomenon. We believe further investigation into this cortisol mechanism link is warranted due to these findings," Marcotte noted.