Anal sphincter trauma during instrumental delivery

Area of Science:

• Obstetrics and Gynecology
• Pelvic Floor Disorders
• Surgical Outcomes

Background:

• Instrumental vaginal deliveries, including forceps and vacuum extraction, are common obstetric interventions.
• Potential complications include maternal trauma, particularly to the anal sphincters and pelvic floor.
• Defecatory dysfunction is a significant and often underreported consequence of childbirth.

Purpose of the Study:

• To investigate the incidence of defecatory symptoms, pudendal nerve damage, and anal sphincter trauma.
• To compare outcomes between forceps delivery, vacuum extraction, and normal vaginal delivery.

Main Methods:

• Prospective study involving 43 women with instrumental delivery (17 vacuum, 26 forceps) and 47 controls with normal vaginal delivery.
• Utilized anal endosonography, manometry, pudendal nerve terminal motor latency (PNTML) testing, and perineometry.
• Assessed for anal sphincter defects and measured anal pressures.

Main Results:

• Women undergoing forceps delivery had a significantly higher incidence of defecatory symptoms (38%) and anal sphincter defects (81%) compared to controls (4% and 36%, respectively).
• Vacuum extraction showed a trend towards increased defects (21%) but was not statistically significant compared to controls.
• Lower anal pressures were observed in women with sphincter defects, irrespective of delivery mode.

Conclusions:

• Forceps delivery is associated with substantially greater anal sphincter damage and a higher risk of defecatory symptoms than vacuum extraction.
• These findings underscore the need for careful consideration of instrumental delivery methods to minimize long-term maternal morbidity.