Obstetric anal sphincter injuries (OASIS), also known as 3rd or 4th degree tears, can lead to loss of bowel control in women (Weinstein et al). The rate of OASIS has increased in recent years, with one study finding the risk of OASIS increases with older maternal age with larger babies and in certain VBAC cases. The researchers also found that an emergency c-section doubled the risk of having an anal sphincter injury later in a VBAC, while having a mediolateral episiotomy cut the risk in half (D’Souza et al 2019).
A new study took a look at the risk of OASIS specifically with an episiotomy. Using hospital data from Canada over the course of 14 years, they found that the overall rate of episiotomies has decreased. “Among spontaneous vaginal deliveries, episiotomy was associated with higher rates of obstetric anal sphincter injury, irrespective of parity and obstetric history” (Muraca et al 2020). However, an episiotomy decreased the risk of OASIS in an operative (forceps or vacuum) vaginal delivery in woman delivering for the first time. Agreeing with the study by D’Souza, they also found that an episiotomy decreased the risk of OASIS in a VBAC delivery, but only if there has been one previous C-section.
The rate of OASIS with an episiotomy is very dependent on the obstetric history of the patient, such as how many children they have had and VBAC history, as well as the type of delivery. In some cases, an episiotomy is found to be protective against an anal sphincter injury, while in others it is thought to increase the risk. This shows how important it is for the obstetrician to be aware of the medical history of the patient to make a decision during labor that will result in the best outcome for both mother and child.
If you suffer complications during labor, you may have a case against the doctor, medical team, or hospital. Call our attorneys now to discuss your case in a free consultation.