Text and Data Mining valid from 2018-10-25
Received: 23 May 2018
Accepted: 12 October 2018
First Online: 25 October 2018
Compliance with ethical standards
: Edgardo Somigliana received during the last 3 years grants of research from Ferring and Merck-Serono. All the other authors do not have any financial disclosure to declare.