Decreasing the incidence of anal sphincter tears in instrumental delivery in Hudiksvall, Sweden.

Purpose: The primary aim of this study was to observe the change in obstetric anal sphincter tear rates in instrumental deliveries during one decade. Secondly, the changes in non-instrumental deliveries were followed.

Methods: Data from all deliveries at Hudiksvall Hospital, Sweden 2010-2011 and 2016-2017 were collected.