A woman’s safety during childbirth can be assessed by looking at potentially avoidable tearing of the perineum during vaginal delivery. Tears that extend to the perineal muscles and bowel wall require surgery. Possible complications include continued perineal pain and incontinence. It is not possible to prevent these types of tear in all cases, but they can be reduced by appropriate labour management and high-quality obstetric care.
The proportion of deliveries involving higher-degree lacerations is considered a useful indicator of the quality of obstetric care. Nevertheless, differences in the consistency with which obstetric units report these complications may make international comparison difficult.
Rates of obstetric trauma may be influenced by other care processes, including the overall national rate of caesarean births, assisted vaginal births (i.e. using forcepts or a vacuum) and episiotomy (i.e. surgical incision of the perineum performed to widen the vaginal opening for delivery of an infant); these remain issues of ongoing research. For example, while the World Health Organization (WHO) (2018[1]) does not recommend routine or liberal use of episiotomy for women undergoing spontaneous vaginal birth, selective use of episiotomy to decrease severe perineal lacerations during delivery remains a matter of debate.
Figure 6.7 shows rates of obstetric trauma with instrument (referring to deliveries using forceps or vacuum extraction) and Figure 6.8 shows rates of obstetric trauma after vaginal delivery without instrument. As the risk of a perineal laceration is significantly increased when instruments are used to assist the delivery, rates for this patient population are reported separately.
High variation in rates of obstetric trauma is evident across countries. Reported rates of obstetric trauma with instrument vary from below 2% in Poland, Israel, Italy, Slovenia and Lithuania to more than 10% in Denmark, Sweden, the United States and Canada. The rates of obstetric trauma after vaginal delivery without instrument vary from below 0.5 per 100 deliveries in Poland, Lithuania, Portugal, Latvia and Israel to over 2.5 per 100 deliveries in Denmark, the United Kingdom and Canada.
While the average rate of obstetric trauma with instrument (5.5 per 100 instrument-assisted vaginal deliveries) across OECD countries in 2017 was nearly four times the rate without instrument (1.4 per 100 vaginal deliveries without instrument assistance), there are indications of a relationship between the two indicators, with Israel, Lithuania, Portugal and Poland reporting among the lowest rates and Canada, Denmark and New Zealand reporting among the highest rates for both indicators.
Rates for both indicators reveal noticeable improvements in Denmark and Norway between 2012 and 2017, but no clear trend is evident in the overall rates of obstetric trauma over the five-year period: the OECD average remained relative static for vaginal deliveries both with and without instrument. In some countries, including Estonia, Italy and Slovenia, rates appear to have deteriorated.
In Canada there has been limited action to address the high rates of reported obstetric trauma. One initiative was the Hospital Harm Improvement Resource: Obstetric Trauma by the Canadian Patient Safety Institute to complement measurement of obstetric trauma by the Canadian Institute for Health Information. It links measurement and improvement by providing evidence-informed resources that support patient safety improvement efforts across the health system.
