One of the most prevalent gynecologic conditions is chronic cervicitis, which primarily affects women who have previously given birth. Approximately 60% of married women experience persistent cervicitis [1]. The clinical symptoms of chronic cervicitis mainly include increased vaginal discharge, mucous purulence, pruritus of the vulva and contact bleeding in severe cases [2, 3].

The are several main treatments of chronic cervicitis [4]. Surgical therapy is the most commonly used method and comprises laser, microwave, cryotherapy, or loop electrosurgical excision procedure (LEEP) [5]. Among these, CO${}_2$ cryotherapy for cervical lesions is a designated treatment method in China’s Guidelines for Comprehensive Prevention and Control of Cervical Cancer, as well as World Health Organization (WHO) Basic Practical Guidelines for Comprehensive Prevention and Treatment of Cervical Cancer [6]. CO${}_2$ cryotherapy uses carbon dioxide refrigerant to quickly reach the ultra-low temperature of minus 67 degrees celsius, and contact is made to the cervical tissue through a low temperature freezing head, so as to achieve the purpose of wound tissue repair [7, 8].

Following surgical therapy, there usually follows adverse reactions, such as continuous vaginal drainage, vaginal bleeding and cervical stenosis, the latter resulting in secondary infertility and cervical dystocia [4, 5]. Kushen gel is a semisolid gel made of a mixture of matrine (C15H24N2O) and carbopol. Matrine is an alkaloid from the traditional Chinese herb medicine sophora flavescens reported to exhibit anti-inflammatory, anti-bacterial, and protective effects [9]. It is a topical preparation that is absorbed through the tissue mucosa without any irritation. Because it is in gel form, the drug can flow evenly to the cervix and every corner of the vagina after being applied [10]. This study aimed to investigate the clinical efficacy and safety of CO${}_2$ cryotherapy combined with Kushen gel for chronic cervicitis.

Many women experience repeated or sustained symptoms of cervicitis. These symptoms can affect the quality of life and marital relationships and consequently, affect the health of the family atmosphere [11]. According to Sukru’s research, there was a statistically significant improvement in vaginal discharge, pelvic pain, and postcoital bleeding symptoms after the cryotherapy [12]. However, Shabnam’s findings highlighted the equal effect of tranexamic acid and cryotherapy for treating cervical ectropion [13, 14]. Chinese traditional medicine believes that cervicitis belongs to leukorrheal diseases, which is mainly due to unsteadiness of Ren and belt channel dysfunction by dampness and heat. The treatment should be based on clearing heat and dehumidification [15]. Kushen gel is a pure Chinese medicine preparation, and its main component is matrine, which has heat-clearing and detoxifying effects as well as antibacterial and insecticidal properties and removes saprophytic muscles [16, 17].

In this study, CO${}_2$ cryotherapy combined with Kushen gel treatment was compared with CO${}_2$ cryotherapy alone. The study demonstrated that the cure rate of both treatments was 100% in patients with mild chronic cervicitis, but the cure rate of patients with moderate to severe inflammation was slightly higher in the combined treatment than in the simple CO${}_2$ cryotherapy group. A significant correlation between cure rate and severity was found; that is, cure rate increased with decreasing severity of inflammation. The reason is that the area with mild cervicitis erosion is small, and the frozen probe makes adequate contact with the treatment area, exerting biological effect to eliminate local inflammation [18, 19]. In terms of postoperative vaginal discharge time, vaginal bleeding time and bleeding volume, Kushen gel makes full use of its advantage as a Chinese herbal medicine, and its unique benefits are conducive to wound healing [20]. Only 5.8% of the patients in the study group had bleeding, with the majority (91.7%) having minimal bleeding. Moderate amount of bleeding was found in only 0.5% of patients. Compared with simple CO${}_2$ cryotherapy, the combined treatment could reduce postoperative vaginal discharge time, bleeding time and amount, shorten the time to wound healing, and promote rapid wound repair.

The postoperative use of Kushen gel makes up for the vulnerability of wound infection after simple CO${}_2$ cryotherapy. Mahira’s study [21] shows that wound infection caused by Enterococcus fecal may become a risk factor for cervical intraepithelial neoplasia. The active ingredients in Kushen gel can quickly enter damaged tissues and increase blood circulation [22]. This feature causes necrotic tissues to separate and exfoliate rapidly, and new epithelium grow rapidly. The gel plays a protective role in cervical wound healing, preventing a wound from being infected by bacteria [23, 24].

There are some limitations of this study. First, randomized clinical trials (RCTs) can draw more reliable conclusions, but we were unable to conduct RCT studies because of the inability to achieve double blinding. Second, we cannot avoid the selective bias due to the patient’s own condition.

The combined treatment of CO${}_2$ cryotherapy with Kushen gel can significantly improve the therapeutic effect and reduce the occurrence of postoperative reactions. Using Kushen gel for the postoperative treatment of chronic cervicitis can significantly improve the quality of life of patients after CO${}_2$ cryotherapy.

The data that support the findings of this study are available from the corresponding author upon reasonable request.

LZ and YZ were involved in the analysis and interpretation of study data, drafting and critical revision of the manuscript; YL and WP were involved in the collection of research subject information; JL was involved in the analysis and interpretation of data; XX and MX were involved in the acquisition of data; SL was involved in the conception and interpretation of study data, drafting and critical revision of the manuscript. All authors contributed to editorial changes in the manuscript. All authors read and approved the final manuscript. All authors have participated sufficiently in the work and agreed to be accountable for all aspects of the work.

The studies involving human participants were reviewed and approved by the research program of the Ethics Committee of Changzhou Maternal and Child Health Care Hospital, NO. 2020. The patients/participants provided their written informed consent to participate in this study. The authors received participants’ consent to publish photographs. This study was conducted in accordance with the Helsinki Declaration of 1964 and its later amendments.

The authors thank Changzhou Maternity and Child Health Care Hospital for their support for this study, and we thank the participants of the study.

Scientific Research Project of Maternal and Child Health of Jiangsu Province (F202166). Key talents in maternal and child health care in Jiangsu Province and Leading Talent of Changzhou “The 14th Five-year Plan” High-Level Health Talents Training Project (2022CZLJ030). 2023 Changzhou Policy Guidance Project (International Science and Technology Cooperation) (CZ20230020), Clinical Research Project of Changzhou Medical Center (CMCC202314), and 2023 Jiangsu Province Traditional Chinese Medicine Science and Technology Development Plan (MS2023089).

The authors declare no conflict of interest.