Endometriosis (EM) is one of the most common gynecological disorders in women of childbearing age, mainly causing progressively worse menstrual pain and infertility. In fact, EM is also the main cause of cyclic or non-cyclic lower abdominal pain in adolescent girls. The incidence of EM in adolescent females with chronic pelvic pain was found to be 45% by laparoscopy [1], while the incidence of EM in adolescents with chronic abdominal pain who had failed to respond to oral contraceptives and nonsteroidal anti-inflammatory drugs was found to be 70% by laparoscopy; and the incidence of EM in adolescents with chronic abdominal pain increased with age, from 12% in 11-13 years to 54% in 20-21 years [2]. This shows that the incidence of EM during adolescence is not lower than that of adult females, but due to its age and other peculiarities, it has not attracted sufficient attention from parents and medical workers, and diagnosis and treatment are easily delayed.EM is a progressive disease, and long-term follow-up [3] found that the clinical stage of the disease at diagnosis is inversely proportional to subsequent fertility. Therefore, early diagnosis and appropriate treatment are particularly important for adolescent EM patients, which can stop the progression of the disease and prevent subsequent infertility. Diagnosis 1, pelvic examination: red lesions are the main form of EM lesions in adolescence, and lesions are mainly located in the rectal uterine sink causing pain, so gentle anal palpation is particularly important for adolescents. The most common sign in adolescent EM patients is tenderness, while nodules may or may not be present. The presence of combined genital tract malformations should also be noted during the examination. 2. Imaging: B-mode ultrasound as a non-invasive examination method has a high detection rate for ovarian endometriosis cysts, and also helps to differentiate them from other gynecological diseases, and is commonly used in clinical practice. Therefore, B-mode can be the first choice of adolescent adjuvant examination for chronic pelvic pain. In addition, CT and MRI can also be used as appropriate, especially MRI has important diagnostic value for adolescent genital tract malformation. 3. serum markers: studies have suggested that the clinical diagnosis of endogynephilia can be made by assessing the changes in serum CA125 levels during menstruation relative to other time periods [4]. Japanese scholars [5] also reported that there was a significant correlation between serum CA199 levels and the Revised American Fertility Society (r-AFS) score. It can be used clinically and also as a monitoring indicator to evaluate the treatment effect. 4, experimental treatment: for adolescents with chronic pelvic pain who are ineffective with oral contraceptives and non-steroidal anti-inflammatory drugs and unwilling to undergo laparoscopy, if they are older than 18 years old, GnRH-a can be used for experimental treatment after ovarian cysts have been excluded, and if the pain is reduced or disappears after treatment, the initial diagnosis of EM can be made [6]. 5, laparoscopy: EM has a higher incidence in adolescents with chronic pelvic pain who are not treated with non-steroidal anti-inflammatory drugs and oral contraceptives, and laparoscopy is recommended for these patients. Laparoscopy has been proven to be the safest and most effective method for diagnosing EM in individuals of any age without contraindications [7]. EM in adolescence is dominated by atypical endometriotic lesions under laparoscopy, mainly presenting as red flame-like, white blister-like, colorless hyaline lesions or small bleeding or petechial spots in the peritoneum of the pelvic wall, and because colorless hyaline lesions are more difficult to detect under laparoscopy, clinicians should be highly alert when exploring the abdominal cavity to avoid missing the diagnosis.The progression of EM from atypical lesions in adolescence to typical lesions in adults may be a natural process. Histopathology can help diagnose pubertal EM, but premenarcheal EM may only show vascular hyperplasia, iron-containing heme deposits, macrophage proliferation, and stroma but no clear glands can be found [8-9], and biopsy tissue specimens are often not available laparoscopically. Second, treatment for EM in adolescence has been previously inferred mainly from studies in adults and applied directly or indirectly to adolescent patients [10]. The aim of treatment is to control pain, stop progression, and preserve reproductive function. Treatment is similar to that of adults and mainly includes expectant therapy, hormonal therapy, and surgical treatment [11]. The most important thing is early diagnosis and early intervention to stop disease progression and reduce the impact on reproductive function. The best treatment option for EM in adolescence is still controversial [12]. (i) Surgical treatment Currently, it is considered appropriate to give treatment along with laparoscopic examination to clarify the diagnosis in this group of patients, and postoperative adjuvant medication (including pain medication) to reduce recurrence, and psychotherapy and education according to the characteristics of adolescents. For adolescent EM patients with combined obstructive genital tract abnormalities, timely genital tractoplasty should be performed to remove the obstruction. After the establishment of normal menstrual blood channels, endometriotic lesions can reduce or even disappear on their own, and they are mostly less likely to recur [13]. Therefore, in adolescent patients with chronic pelvic pain, dysmenorrhea or pelvic masses, pelvic examination should be carefully performed and attention should be paid to the condition of the uterus, adnexa, uterine rectal sink and uterosacral ligament, as well as whether there is a combined genital tract abnormality. Once the diagnosis of genital tract malformation combined with adolescent endometriosis is confirmed, the cause of endometriosis should be removed by surgery as soon as possible, and efforts should be made to protect the future reproductive function of adolescent girls from being affected. For adolescent patients with chronic pelvic pain, dysmenorrhea or pelvic masses without reproductive tract abnormalities, laparoscopy is the preferred method of examination and treatment. Laparoscopic surgery is less invasive, with light postoperative pelvic adhesions, and is the currently accepted method for confirming the diagnosis of endometriosis. Therefore, for adolescent patients, laparoscopic diagnosis and treatment is the best surgical approach. The specific surgical procedures are the same as those used for adult EM, such as electrocautery of small ectopic lesions in the pelvis, disintegration of adhesions, and debridement of cysts, while preserving reproductive function as much as possible. However, the electrodesis and electrocoagulation used in laparoscopy can easily cause damage to the ovarian tissue. Therefore, care should be taken to carefully peel away the ectopic cyst wall, preserve as much normal ovarian tissue as possible, stop bleeding with electrocoagulation as little as possible, and use sutures to stop bleeding, thus reducing damage to ovarian tissue. Open surgery is often performed with sharp separation and suture hemostasis, thus affecting ovarian function less, but the disadvantage is that the surgical incision is large and postoperative adhesions in the pelvis are easily caused. Therefore, the advantages and disadvantages should be weighed and the best surgical approach should be determined according to the patient’s specific situation. In cases of mild endometriosis or rupture of ectopic cysts during stripping, intraoperative flushing of the abdominal cavity with large amounts of saline is beneficial to improve the pelvic microenvironment and reduce postoperative recurrence. (ii) Medication is needed to control pain and inhibit hormone secretion in postoperative EM patients during puberty, so as to slow down the progression of the disease and reduce recurrence, and the medication usually needs to be continued until the completion of reproductive function. The choice of medication must take into account the patient’s age, the severity of symptoms, and the stage of the disease. Commonly used postoperative treatments are as follows: 1. Oral contraceptive pills (OCP): they are the first line of treatment for adolescent EM patients and are safe and effective for EM patients less than 16 years of age [6]. The continuous application of estrogen and progestin can lead to amenorrhea and metaplasia of ectopic endothelial lesions, resulting in improvement of pain with fewer side effects.OCP is often used in combination with nonsteroidal anti-inflammatory drugs and is mostly effective in controlling EM-related pain. It has no expiration date and can be taken continuously or periodically because of its ease of use, positive efficacy, and no significant effect on height, weight, body mass index (BMI), and recent body fat percentage in adolescents [14]. Its most common side effect is irregular vaginal bleeding, which is mostly mild and disappears after discontinuation of the drug. Commonly used drugs include daing-35 and mafron. 2. Pregnant trienone: It can act directly on the ectopic lesion, causing it to atrophy and degenerate, and symptoms such as dysmenorrhea are obviously relieved. It is effective in treating dysmenorrhea symptoms of endometriosis and has less adverse effects than danazol, so it can be used in adolescent EM patients. 3, Danazol: Although Danazol is effective for EM patients with dysmenorrhea symptoms, it is often not accepted by adolescent EM patients because of its obvious androgen-like effects, including side effects such as weight gain, hirsutism, acne, and centripetal obesity, so it is not recommended that adolescent EM patients should have Danazol [15]. 4. progestins: progestins have few side effects and are a good choice for long-term treatment of adolescent EM patients [16], with medroxyprogesterone (MPA) being the most commonly used. However, studies have shown [17] that MPA is the least tolerable and least effective in pain relief compared with combined oral contraceptives, gonadotropin-releasing hormone agonist ( GnRH-a), and analgesic drugs [6], and is therefore not recommended. 5, GnRH-a counter-additive therapy: GnRH-a is currently recognized as the most effective drug for the treatment of adult EM, and also has good efficacy for adolescent EM, but because its main side effect is to cause changes in bone density, for adolescent patients who have not yet reached peak bone density, the application of this drug has a certain effect on bone deposition, so the application of GnRH2-a should take a cautious attitude. In patients where contraceptives are ineffective, GnRH-a plus-plus-plus therapy, i.e., simultaneous administration of haumeaestrol 0.625 mg plus methacholine 2 mg 1 P d or 17-alpha isonorgestrel 2.5 mg 1 P d, can be used to prevent bone loss. Many studies have now proposed that GnRH-a combined with counter-additive therapy reduces adverse effects and does not compromise efficacy [18]. gnRH-a can cause pharmacological oophorectomy and has a significant inhibitory effect on ectopic endometrium, but it does not completely eliminate the ectopic foci and may recur after discontinuation of the drug, also confirming that endometriosis symptoms are persistent and require long-term and repeated pharmacological treatment. Therefore, it is recommended that continuous or cyclic oral contraceptives be used as the first-line regimen for pharmacological treatment in adolescent EM patients ≤16 years of age, and GnRH-a may be considered in EM patients >16 years of age [6], but the course of treatment should not exceed three months. 6. other drugs: recent studies on immunotherapy with BCG have made it promising as a new approach for the treatment of endometriosis. bcg can be used to treat endometriosis by directly inhibiting the implantation of endometrial cells, enhancing the humoral and cellular immune functions of the endometrium, myometrium and local lymph nodes, and enhancing the killing effect of peripheral blood mononuclear cell-mediated killer cells on the endometrial stroma. However, further animal experiments and clinical studies are still needed, and some potential problems with the application of BCG need to be noted, such as the possibility of causing BCG sepsis, which is lethal despite its low incidence; in addition, BCG can cause inflammatory reactions [19]. Another study found that interferon, as an important immunomodulatory factor, can inhibit the proliferation of endometrial cells, inhibit the formation of neovascularization, increase the activity of macrophages, and enhance the body’s ability to clear ectopic lesions, which is feasible for the treatment of endometriosis and still needs further study [20]. (iii) Comprehensive treatment Ballweg [17] emphasized the psychological treatment of adolescent EM, i.e., capturing the psychophysiological characteristics of adolescents and providing psychological support such as encouragement and comfort.Greco [21] believed that the combination of adolescent EM medication with cognitive-behavioral therapy, physical therapy, and other methods can alleviate the symptoms of lower abdominal pain in adolescent EM patients, thus improving their life quality of life. In conclusion, the incidence of adolescent EM is similar to that of adults, it is multifactorial, and no single doctrine can explain the onset of all adolescent patients. Clinical symptoms tend to be atypical abdominal pain or periodic lower abdominal pain, while laparoscopic manifestations tend to be atypical lesions such as red lesions. Adolescents with chronic abdominal pain and dysmenorrhea should seek early medical attention and laparoscopy should be performed as early as possible for definitive diagnosis in suspected endometriosis. Early diagnostic methods have yet to be explored. The goals of EM treatment in adolescence are mainly to control pain, delay progression, and preserve reproductive function. Laparoscopic diagnosis and treatment is the preferred surgical procedure, and postoperative adjunctive medication is required to reduce pain and prevent recurrence. Oral contraceptives are the first line of treatment, and GnRH-a should be used with caution in adolescents under 16 years of age to avoid affecting bone development. Individualized treatment should also be provided from multiple psychological, psychiatric, and cognitive-behavioral aspects.