An editorial published in BMJ has challenged the idea of using drugs that delay preterm birth.

Children born preterm, born before 37 weeks of gestation, tend to have lower cognitive abilities and are at a high risk for many health complications. Doctors usually give tocolytics to delay a premature delivery.

Tocolytic drugs give doctors ample time to give steroids to the fetus that would quicken the development of lungs. The delay in delivery also means that there is more time for healthcare professionals to transfer the mother to a hospital where there is a neonatal intensive care unit. These drugs can be used to delay delivery for up to 48 hours.

However, Professor Zarko Alfirevic, from the Department of Women's and Children's Health at the University of Liverpool, says that a latest study on the efficacy of tocolytics in delaying preterm births shows no evidence that the use of the drugs will lower the risk of illnesses in the newborn.

Professor Alfirevic says that drugs aiming at prolonging delivery need to be re-examined for their role in preventing other risk factors for the newborn.

A recent study by David M. Haas, associate professor of obstetrics and gynecology from the Department of Obstetrics and Gynecology, Indiana University School of Medicine, and colleagues, also published in BMJ, says that prostaglandin inhibitors and calcium channel blockers had the highest probability of delaying pregnancy. A 2011 update on tocolysis had said that while prostaglandin inhibitors were safe to use, drugs that are calcium channel blockers need to be used with caution because they have been known to cause serious health complications like cardiac failure in people who have heart-related problems.

Professor Alfirevic says that doctors must be honest about the drugs when they give them to the mothers because these drugs may delay delivery but may not provide any real benefit to the baby. In conclusion, Alfirevic hopes that "babies are not coming to greater harm by our attempts to keep them in utero."