Laparoscopic myomectomy, caesarean section tied to uterine rupture

A significant change in the trend of uterine rupture cases has been observed in Singapore due to the increasing use of laparoscopic myomectomy and elective caesarean sections, reveals a study. These ruptures are few, but their presentation in the antenatal period requires careful monitoring with informed patient involvement in their pregnancy care.

“Meticulous review of previous surgical documentation and photos, detailed counselling, close follow-up, and early identification of these at-risk patients is crucial to optimize outcomes for uterine rupture cases,” the researchers said.

“Unscarred uteri can also rupture. Discreet enquires about previous uterine instrumentation at the booking visit could help identify some women at risk,” they added.

This retrospective observational study was conducted at KK Women’s and Children’s Hospital, analysing proven cases of uterine rupture between January 2003 and December 2014. The researchers examined these cases based on their history, clinical presentation, complications, management, and outcome.

Forty-eight cases of uterine rupture were identified, with an incidence of one in 3,062 deliveries. The ratio of scarred uterus rupture to unscarred uterus rupture stood at approximately 3:1. [Ann Acad Med Singap 2021;50:5-15]

Previous lower segment caesarean section for the scarred group was the most common factor, followed by a history of laparoscopic myomectomy. Of note, a uterine rupture had been shown to correlate with previous uterine scars, which was normally due to a history of prior caesarean sections. [WMJ 2006;105:64-66]

Additionally, the most common clinical presentation in the antenatal period was abdominal pain, while abnormal cardiotocography findings most presented in intrapartum rupture.

“One of the most important risk factors in uterine rupture is a history of laparoscopic myomectomy,” the researchers said. “The second most common cause of scarred uteri in our case series is a previous history of laparoscopic myomectomy.” [J Med Ultrason 2016;43:133-136]

All rupture cases had a history of laparoscopic myomectomy, and none of the cases were from an open myomectomy. The rupture rates following laparoscopic myomectomy varied, reaching as high as 10 percent. [Hum Reprod 2000;15:869-873; Surg Technol Int 2006;15:123-129; J Minim Invasive Gynecol 2007;14:453-462; Arch Gynecol Obstet 2014;290:87-91; J Minim Invasive Gynecol 2015;22:1022-1028]

“The technique of repair with laparoscopic suturing following myomectomy could be a contributing factor to the integrity of the scar subjected to a trial of labour,” the researchers said.

Bernadi and colleagues, in their single-centre cohort study, suggested the following factors associated with the incidence of uterine rupture after myomectomy: short duration between myomectomy and conception (<12 months), opening of endometrial cavity, and patients with large myomas >4 cm. [Arch Gynecol Obstet 2014;290:87-91]

Previous studies have also shown that extensive use of electrosurgery results in poor vascularization and necrosis of the myometrium, reducing scar strength and predisposes to uterine rupture. [Hum Reprod 2000;15:869-873; Arch Gynecol Obstet 2014;290:87-91; Taiwan J Obstet Gynecol 2018;57:304-310]

“Appropriate use of electro-surgery and multilayered closure of the myometrium are essential for the prevention of uterine rupture after a laparoscopic myomectomy,” the researchers said. “Avoidance of entry into the endometrial cavity and prevention of haematoma formation are also extra precautions.” [J Minim Invasive Gynecol 2010;17:551-554]