At present, there is no consensus on whether to perform cesarean section myomectomy, especially large intermural myoma, for women with uterine leiomyoma during pregnancy . Considering the increased risk of postpartum hemorrhage and perinatal hysterectomy, most of the literature strongly opposes myomectomy after cesarean section and believes that it is safer to leave the myoma in situ for a second operation . However, there were still many scholars who hold a different view . In view of the fact that huge uterine fibroids may lead to poor involution of the uterus and will not fade by itself, it is recommended that hysteromyomectomy should be performed at the same time of cesarean section in order to reduce puerperal complications and psychological and economic burden caused by uterine fibroids and avoid further surgical intervention . Rong, Zhao, Dedes I et al [13, 14] reported that myomectomy can be considered during caesarean section for uterine fibroids ≤ 5 cm in diameter, whereas for uterine fibroids > 5 cm in diameter, intraoperative haemostasis is difficult and bleeding is significantly increased, so caesarean myomectomy should be careful. Dam Hye Kwon  et al. concluded that there was no significant difference in intraoperative bleeding, operative time and length of hospital stay when myomas > 5cm in diameter were removed during caesarean section compared to those ≤ 5cm in diameter, and concluded that large myomas > 5cm in diameter were safe to remove during caesarean section. A study by Shi Xinwei et al  found that cesarean myomectomy was safe and feasible, but for uterine fibroids > 8 cm in size, the operative time and intraoperative bleeding increased significantly and caution was needed . So, if the uterine fibroid > 8cm in diameter, is it necessary to remove it during caesarean section? Is the procedure safe? Does it increase the risk of postpartum haemorrhage and hysterectomy? This is the purpose of this study.
Is it necessary to remove large intermural myoma during cesarean section? Some studies suggests[17, 18] that giant myomas may affect uterine contraction, increase the risk of postpartum hemorrhage and infection, and are forced to remove the uterus due to refractory postpartum hemorrhage or severe infection. Hysteromyomectomy by caesarean section can avoid a second operation in 90% of patients with large myoma and reduce the need for hysterectomy due to excessive growth of myoma in the future. In the current study, comparing the intraoperative blood loss between the regular group and the control group, we found that the amount of intraoperative blood loss in patients unresected uterine leiomyoma was significantly higher than that in patients without uterine leiomyoma (P < 0.001). We also found an interesting phenomenon that the rate of Bakri balloon implantation in patients with unresectable uterine fibroids during cesarean section was the highest among the three groups (P < 0.001). What is the reason for this? In the study group, after myomectomy, the wound was quickly sutured to restore muscle fiber integrity, resulting in better contraction and less subsequent bleeding. However, in patients who do not undergo myomectomy during cesarean section, uterine fibroids cause uterine weakness, leading to persistent uterine bleeding. In addition, we found a patient in the regular group who developed persistent abdominal pain and fever for 13 days, which was thought to be caused by secondary infection caused by myoma degeneration. In the study, we also found that 90.9% of patients without cesarean section underwent laparoscopic myomectomy at a later stage. In short, under the premise of ensuring the safety of the operation, myomectomy for cesarean section is advocated.
Is myomectomy safe and feasible for large intramural myomas larger than 8cm in cesarean section? Tjokroprawiro B An et al.  reported that myomectomy was successfully performed in two cases of large myoma larger than 15cm in diameter. Ma et al.  also reported that hysteromyomectomy for 40 cm-sized uterine leiomyomas was successful during cesarean section after bilateral uterine artery ligation. However, due to the small sample size, these researchers did not conduct group studies to assess the safety of surgery. This is the significance of this study. Our study compared the surgical results of myomectomy in cesarean section with that without myomectomy in cesarean section. In addition to the operation time, the hysteromyomectomy group was significantly longer in cesarean section, and there was no statistical difference in intraoperative blood loss, antibiotic use time, postoperative hospital stay and anal exhaust time. And there were no long-term complications. Therefore, we believe that cesarean section of large interstitial fibroids larger than 8cm is safe and feasible for experienced obstetricians and gynaecologists.
Operational experience of cesarean myomectomy in patients with large interstitial myoma. Firstly, the surgeon must be able to perform uterine artery ligation and hysterectomy. All the cesarean myomectomy in our current study were performed by the same Chief Obstetrician. Secondly, the improvement of surgical skills. Before myomectomy, we bind the lower segment of the uterus with a compression band to block the blood supply and reduce intraoperative bleeding. The choice of incision for myomectomy of intramural uterine leiomyoma, we choose the incision according to the classification of leiomyoma to avoid all myomas cut from the serous layer of uterus, type III and V uterine leiomyoma, we choose to cut open from the endometrial layer, which can reduce intraoperative bleeding, shorten operation time, and avoid intestinal adhesion and intestinal obstruction after operation. However, type IV and VI uterine leiomyomas are still cut from the serous layer. With regard to the suture of the myoma wound, considering that the tumor cavity is deep after large intermural myomectomy, we give up the traditional continuous double suture with 1 − 0 micro-Joe thread, and use No. 1 polysorb CL-905 absorbable thread to close the tumor cavity, and then use 2 − 0 micro-Joe thread continuous mattress suture to compress and embed the wound. This can not only avoid dead space, but also reduce muscle layer tear and needle eye bleeding in the process of suture.