This study to evaluate the factors that determine complications during pregnancy associated with uterine leiomyoma provided important information for managing women’s health. The incidence of uterine leiomyoma is continuously increasing, uterine surgery using robot including laparoscopic myomectomy has also increased. In particular, when uterine leiomyomas are present in young women of childbearing age or myomectomy has been performed, pregnancy-related problems and various complications may occur. Preterm labor, placental problems, and uterine rupture are particularly serious obstetrical problems, so research on pregnancy, uterine leiomyoma, and myomectomy is very important.
The mean gestational age at delivery was significantly lower in the CM group and this might have been due to the increased contractility of the myometrium with the presence and mass effect of the leiomyoma [9]. For similar reasons, the incidence of preterm labor was increased significantly in the CM group in our study. In addition, although not statistically significant, there was a higher rate of abnormal fetal presentations in the CM group, suggesting that the presence of leiomyomas affected fetal malpresentation [10, 11].
Our data suggested a significant difference (8 min) in the duration of surgery between the groups. In a previous report, the operation time was 4.94 minutes longer in the CM group than the CS-only group, which was not a significant difference [12]. In another study, the operation time in the CM group was 15 minutes longer than that of the CS-only group and this was a significant result [9].
The history of a previous myomectomy was significantly higher in the CS-only group than in the CM group. This may have been because the patients who underwent a previous myomectomy were likely to have fewer or no leiomyomas, so only a CS was performed. The history of a previous CS was significantly higher in the CM group. The probable reason for this was to prevent additional surgery due to remnant leiomyomas in the future.
Generally, CM has been controversial and is not recommended routinely. This is because CM tends to increase the rate of intraoperative or postoperative hemorrhage, and in the worst case, leads to hysterectomy, which surgeons fear, and pelvic adhesions due to bleeding. A meta-analysis was conducted in 2017 examining 19 studies and comparing a total of 2,301 patients who underwent CM with patients who underwent only CS [13]. This study reported that the group that underwent CM had a greater decrease in Hgb levels and needed more blood transfusions (mean difference in Hgb 0.25 mg/dL, 95% CI: 0.06 – 0.45; risk of transfusion OR: 1.41, 95% CI: 0.96 – 2.07). In contrast, in a retrospective cohort study conducted in 2019, no differences were detected in terms of average Hgb decreases or blood transfusion rates between the patients who underwent CM and the patients who underwent only CS [14]. Similarly, in our study, we did not find any significant differences between the groups in hemoglobin level decreases or blood transfusion rates. In addition, postoperative complications such as the incidence of postpartum hemorrhage, postoperative insertion of intrauterine balloon tamponade, or hysterectomy also showed no significant differences. Therefore, CM is a reliable and safe approach, preventing the need for future operations.
Many factors should be carefully considered before performing CM such as the patient’s condition, location of the leiomyoma, emergency status of the surgery, and the surgeon’s skill. In particular, the surgeon’s skill and preference for CM are likely to play an important role because CM can be associated with operative complications.
Pregnancy-related uterine rupture after myomectomy should be dangerous complication in mother and fetus. Gambacorti et al. reported that labor after myomectomy was associated with a 0.47% risk of uterine rupture [15]. According to a study by Koo et al., uterine rupture during pregnancy occurred in only three (0.6%) cases out of 523 patients who underwent laparoscopic myomectomy [16]. This study concluded that laparoscopic myomectomy is a safe surgical option for women who desire pregnancy. However, studies on the correlation between CM and uterine rupture are very scarce. Additional research and investigation are required for a better understanding of the relationship.
Standardized indications for CM have not yet been defined. As can be derived from our results, the characteristics of leiomyomas in the CM group were mostly subserosal type, singular or fewer than three in number, or large in size. This seems to be a result of surgeons considering the risk-benefits of CM to avoid risk during surgery. According to a study by Zhao et al. [14], the presence of a leiomyoma larger than 5 cm and birth weight of more than 4,000 g were the important risk factors for postpartum hemorrhage of ≥ 1,000 ml in pregnant women with leiomyomas during CS, whereas the location and type of leiomyoma had little effect. Kwon et al. reported that large size exceeding 8 cm and lower segmental position of the leiomyoma were significant risk factors for intraoperative hemorrhage during CM [17].