The dramatic rise in preterm births is due to the increase in C-section deliveries in the United States, a new study reveals.

Newborns are considered premature when they are delivered prior to 37 weeks of gestation. According to a previous study by researchers from Duke University Medical Center, published in the March 26 issue of the Journal of the American Medical Association, about one in eight births (totaling more than 520,000 babies) in the U.S. is premature. The bad news is that about 60 percent of babies born at 26 weeks of gestation have long-term disabilities, such as chronic lung disease, blindness, deafness and neurodevelopmental problems or worse they are three time more likely to die during the first year of life, especially in the first month of life. That number drops to 30 percent for babies born at 31 weeks.

In fact, no further than last week, U.S. Centers for Disease Control and Prevention’s National Center on Birth Defects and Developmental Disabilities, the March of Dimes Foundation and several other organizations made a study, according to which, preterm babies have double the risk to be born with major birth defects than-full-term infants.

For the new study, researchers from the March of Dimes, the U.S. Centers for Disease Control and Prevention, and the Albert Einstein College of Medicine looked at national birth data from 1996 to 2004 and found an increase of almost 60,000 singleton preterm births, most of those delivered by C-section.

“The analysis revealed that 92 percent of the increase in singleton premature birth is due to C-sections. That is amazing statistic,” Dr. Alan Fleischman, medical director and senior vice president of the March of Dimes, said, as quoted by the Washington Post.

According to the American College of Obstetricians and Gynecologists, a C-section should not be performed unless there are medical indications for it. However, this is not what reality shows, many of the C-sections being performed at the mothers’ request.

“To do an elective C-section without a medical indication 20 years ago would have been unheard. Ten years ago, it was very controversial. Now it is much less controversial. Many are done today because mother wants it,” Bruce Flamm, an obstetrician-gynecologist at UC Irvine who was no involved in the study was quoted as saying the LA Times.

In consequence, the proportion of infants delivered by C-section has increased from 5 percent in 1975 to 30 percent nowadays. C-sections have become the most common surgical procedures for women and risk factors such as hypertension, obesity and diabetes (that would prevent a woman deliver her baby the natural way) do not fully explain the increase in C-section deliveries, Joann R. Petrini, PhD, MPH, of the March of Dimes told WebMD.

The findings of the new study were published in the June issue of the journal Clinics in Perinatology.