Correction to: Journal of Perinatology; https://doi.org/10.1038/s41372-018-0057-3; published online 5 April 2018

The original HTML version of this Article incorrectly showed the copyright holder to be ‘Nature America, Inc., part of Springer Nature’, when the correct copyright holder is ‘The Authors 2018’. This has been corrected in the HTML version of the Article. The PDF version was correct from the time of publication.