Congenital cervical atresia is a relatively rare Müllerian duct anomaly of the female reproductive tract that was first reported by Ludwig in 1900. It is associated with acute or chronic abdominal or pelvic pain and reproductive problems [1, 2]. The management of women with congenital cervical atresia remains controversial [3].

Congenital cervical atresia must be classified, so that the condition can be considered distinct from other Müllerian duct anomalies in terms of diagnosis and treatment selection. Four systems have been proposed for the classification of congenital cervical atresia [4]: the system of the American Fertility Society (now the American Society of Reproductive Medicine) [5]; the embryological-clinical classification system of genito-urinary malformations [6, 7]; the ‘Vagina, Cervix, Uterus, Adnex-associated Malformations’ system, which is based on the ‘tumor nodes metastases’ principle in oncology [8]; and the new European Society of Human Reproduction and Embryology/European Society for Gynaecological Endoscopy classification system developed by the CONUTA working group [9]. These classifications have limitations in terms of effective categorization of anomalies, simplicity, and clinical application [9].

Surgical interventions for congenital cervical atresia range from complete hysterectomy with canalization to conservative options, such as uterine cavity catheterization [10–14]. As a high level of surgical expertise is required to conduct complex reconstructive procedures, many clinicians choose hysterectomy as the optimal primary surgical treatment for the malformation [15].

Most reports on congenital cervical atresia in the literature refer to individual cases. Owing to the clinical importance of congenital cervical atresia, studies including large numbers of patients will be useful to understand the pathogenesis and management of the condition [16]. In this study, we retrospectively studied the clinical characteristics of 32 cases of congenital cervical atresia during preoperative ultrasound and intraoperative exploration. Based on our findings, we identified four types of congenital cervical atresia. Classifying congenital cervical atresia according to anatomy and ultrasound may inform diagnosis and treatment strategy.

Anatomical characteristics of individual cases of congenital cervical atresia should be considered distinct from other Müllerian duct anomalies in terms of diagnosis and treatment selection. Our observations of clinical characteristics during preoperative ultrasound and intraoperative exploration identified four types of congenital cervical atresia. Type I cervical atresia is characterized by a normal functioning anatomic internal os, a relatively large hematoma cyst, and accumulations of blood in the uterine cavity. In Type II cervical atresia, a shortened cervix and detached sacrum and main ligament may resemble Müllerian fusion of the middle and tail sections [17]. Type III cervical atresia is characterized by long and solid tissues below the uterine body, wherein both the uterine isthmus and cervical canal are atresic. In Type IV cervical atresia, the cervix attaches to the normal ligament and connections form between the uterine body and the blind end of the cervical canal. Absence of the uterine isthmus is characteristic of Type IV, resulting in expansion of the uterine cavity and blood accumulation during menstruation.

Observations of the anatomical characteristics of cervical atresia can provide a guideline for selection of appropriate surgical techniques. For Type I cervical atresia with a normal uterine body, vaginal and cervical reconstruction was performed with perineal surgery (Figure 9; Figure 3). The uteri of Type I patients who underwent restorative surgery for cervical atresia could be successfully preserved. Type I cases were generally able to retain uterine structures, reduce dysmenorrhea, and had the potential to achieve natural pregnancy. In some patients, the reconstructed cervix formed the lower uterine segment during pregnancy, and the patients underwent successful lower uterine segment Cesarean Section. A total of 60% of Type I patients received appropriate treatment and preserved their physiological and reproductive function. For Type II and III cervical atresia, hysterectomy was performed and vaginoplasty was carried out. For Type IV cervical atresia, the treatment principles were similar to those of Types II and III cervical atresia. The uterus could be preserved if the patients requested. However, as the patients of Type IV cervical atresia had no uterine isthmus, the lower uterine segment during pregnancy could not be formed, and the patients were infertile [18].

While further studies will be required to extend our observations, knowledge of clinical characteristics of congenital cervical atresia obtained during preoperative ultrasound and intraoperative exploration may improve treatment outcomes, including the reduction of recurrent atresia, a decrease in long-term dysmenorrhea, and the retention of reproductive capacity. Additionally, the risk of post-surgical hysterectomy may be reduced. The results from this study should be interpreted in terms of novel treatment approaches for congenital cervical atresia, such as combined retropubic balloon vaginoplasty and laparoscopic canalization and laparoscopic canalization under vaginoscopic monitoring [19, 20], which represent minimally invasive management techniques with promising short-term outcomes.

In summary, we explored the anatomic location, ultrasonic features, surgical treatments, and outcomes of 32 cases of congenital cervical atresia. We identified four distinct types of congenital cervical atresia, which provided a guideline for selection of appropriate surgical techniques. Our results may provide insight into the development and use of novel treatment approaches for congenital cervical atresia.