A New Record (image) Brown University Share Print E-Mail Caption In 2014 US moms gave birth to more twins per 1,000 live births than ever, according to the CDC. Implemented differently than in the past, IVF, a technology partly responsible for the increase, could help the rate come back down. Credit Brown University/CDC Usage Restrictions with credit Share Print E-Mail Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.