This is because the babies are unable to undergo hormonal and psychological changes, such as the draining of their lung fluid, they experience during labor. These changes aid in maturing the lungs, BBC News reported.
The study, done by the University of Aarhus and published in the British Medical Journal showed such babies are up to four times more prone to have lung problems compared to those born through natural childbirth, or by emergency Caesarian section, BBC News added.
The study involved 34,000 deliveries.
BBC News said doctors are set to study whether mothers undergo birth by Caesarian section either because mothers request for it, or doctors perform method for convenience.
A consultant obstetrician at King's College Hospital in London, Dr Maggie Blott stressed that obstetricians in the United Kingdom were told not the perform elective Caesarians if the fetus is less than 39 weeks, BBC News added. She said many women as complete unaware "of the fact that a planned Caesarean section can negatively impact on their baby."
In 1999, BBC reported that in the 1950s, less than three percent of women underwent Caesarian sections when they were giving childbirth. The figure rose to 10% in the 1980s.
The World Health Organization has said that for countries in the developed world, the acceptable Caesarian section rate is 10 to 15%, BBC News added.
