Who is at risk of endometrial cavity breach at laparoscopic myomectomy?

BACKGROUND: Submucous and large intramural fibroids cause heavy menstrual bleeding and can negatively impact reproductive outcomes. Large submucous and non-cavity distorting fibroids need to be removed laparoscopically. One of the risks of a laparoscopic myomectomy is breaching the endometrial cavity and there have been suggestions that this increases the risk of intrauterine adhesions. The aim of this study was to examine the role of various demographic and pre-operative ultrasound variables at predicting the risk of endometrial cavity breach during laparoscopic myomectomy. METHODS: This was a retrospective study of women who underwent a laparoscopic myomectomy. Women who had more than one fibroid removed and women who did not have pre-operative ultrasound images available were excluded. The size of the fibroid, minimum distance from the endometrial cavity, surface area, intra-cavity surface area, protrusion ratio and extra-cavity size as well as the women’s age, parity and pre-operative GnRH analogue use were recorded. The outcome measure was the breach of the endometrial cavity at myomectomy. Univariate analysis was performed to identify variables that are associated with a cavity breach. A logistic regression analysis was used to identify the most significant predictor of a breach. RESULTS: A total of 66 women were included in the study. From these, 10 women sustained a cavity breach. All pre-operative ultrasound variables, i.e. minimum distance of the fibroid from the cavity (p=0.001), protrusion ratio (p=0.001), total surface area (p=0.020), intra-cavity surface area (p=0.001), size (p=0.030) and extra-cavity size (p=0.001) were statistically different between the group that had a cavity breach and the group that did not. In a logistic regression model, protrusion ratio was selected as the best predictor of a breach (OR 1.22; 95% CI 1.10 – 1.37). All breaches occurred in women who were not given GnRH analogue. CONCLUSION: Identifying patients at increased risk of a cavity breach facilitates better individualized pre-operative counselling regarding the risk of a breach and the possibility of intrauterine adhesions. It will also trigger more intra-operative vigilance to minimize the risk of breaching the cavity and, subsequently, the risk of intrauterine adhesions if a breach does occur.