In this study, we retrospectively analyzed outcomes in 248 patients who underwent vaginal repair surgery between January 2012 and December 2014. In all, 193 of them had one prior cesarean section, while 55 had two.
Recent analyses have suggested that while the optimal global cesarean section rate is almost 20%, attempts to reduce cesarean section rates in developed countries have not worked. In China, the rate is approximately 35%, and the incidence of acquired diverticulum ranges from 4-30% and is mainly caused by poor healing following a cesarean section scars[6, 10].
Our country has enforced a two-child policy in recent years. Thus, many women have a cesarean section before they desire to have a second child. In these CSD patients, infertility is more common because the accumulated blood degrades the quality of sperm and the cervical mucus. However, because the remaining muscular layer is thinner as a result of CSD, the risk of uterine rupture is significantly higher. Finally, with the promotion of the two-child policy, women who previously underwent one cesarean section are now more likely to experience two cesarean sections. Some of these women may experience abnormal uterine bleeding, which mainly presents as a longer duration menstruation period, compared to what had occurred before the cesarean section. Therefore, due to its long-term complications, CSD has recently received attention from more doctors.
Oral contraception is considered a conservative management option to treat CSD patients who have had two cesarean sections. One study showed that oral contraceptives improved patient symptoms by decreasing the volume of menstruation. However, considering the ages of the affected patients, the use of oral contraceptives is controversial because of its potential risk of vein thrombosis.
Operative methods include hysteroscopy, laparoscopy and vaginal repair. Studies have indicated that compared to other surgical methods, vaginal repair for CSD is a minimally invasive procedure that allows good exposure and accurate resection [7, 14, 20, 22]. It also clearly shortened the duration of menstruation and significantly increased the distance between the CSD and the serosa. Additionally, transvaginal repair may be a more cost-effective and convenient surgical approach for the management of patients with previous cesarean scar defects.
For patient with two prior cesarean sections, the main objectives are to shorten the duration of menstruation and improve quality of life. However, regarding the clinical effectiveness after vaginal surgery, whether women with two prior cesarean sections achieve better outcomes following this procedure has remained unclear.
Xu HY et al found that repeated cesarean section is a risk factor for poor efficacy of scar repair, whether performed by laparoscopic surgery or transvaginal surgery (OR 9.75, 95%CI 2.30-41.36, 0.002). Nevertheless, in our study, we found that the duration of menstruation was significantly shorter after surgery in both groups (P< 0.05). However, there was no significant difference between the two groups (P> 0.05).
Another main symptom of CSD is a thinner remaining muscular layer. Compared to the data obtained before surgery, at the 3-month and 6-month follow-ups, there were significant differences in the size of the CSD as well as the TRM (P< 0.05). After vaginal repair, the average TRM was higher in group B than in group A. Hence, women with two prior cesarean sections achieved better outcomes than were achieved by those with one prior cesarean section. Finally, no complications, such as incomplete healing of the scar and bladder injury, were reported in the two groups.
In addition, there was an unknown problem. Before vaginal repair, the TRM was clearly higher in women with two prior cesarean sections than in those with one. According to some researchers, the cesarean section technique (i.e., single- or double-layer closure, whether or not a bladder flap is created, and closing of the peritoneum) plays an important role in niche development, and it has been proposed that placing continuous, nonlocking absorbable sutures in two layers without undue tightness (constricting/devascularizing) of the sutures is likely to result in good healing of uterine scar. More research is needed to elaborate this point.
There are some limitations to our study. First, the sample size was limited in this paper, especially with regard for women with two prior cesarean sections. Second, the patients were seen for follow-up visits only after 3 and 6 months, and we need more follow-up data, particularly after 6 months, to determine long-term clinical effectiveness.