A population-based register study to determine indications for episiotomy in Finland

Abstract

Objective To evaluate whether there is a shift in the episiotomy target group from women at low risk to those at high risk of obstetric anal sphincter injuries, concomitant with a decrease in the use of episiotomy. Methods A population-based register of 514 741 women with singleton vaginal deliveries recorded in the Finnish Medical Birth Register was reviewed. Primiparous and multiparous women with episiotomy were compared to women without episiotomy for possible risk factors via stepwise logistic regression analysis. The prevalence and risk of episiotomy were evaluated over 5 time periods from 1997 to 2007. Results The occurrence of episiotomy decreased from 71.5% in 1997–1999 to 54.9% in 2006–2007 among primiparous women, and from 21.5% in 1997–2001 to 9.2% in 2006–2007 among multiparous women. The use of episiotomy decreased in not only low-risk but also high-risk women who had operative vaginal or breech deliveries, macrosomic newborns, and oxytocin augmentation. The ratio of episiotomy use remained relatively unchanged in different subgroups even though episiotomy policy became increasingly restrictive over time. Conclusions The spectrum of episiotomy indications has not changed over time, and use of episiotomy has declined arbitrarily to a similar extent among high- and low-risk women.