Only patients who sign an informed consent will be included. Patients after a miscarriage in the 2nd trimester of pregnancy who need to perform an instrumental revision of the uterine cavity (RCUI, revisio cavi uteri instrumentalis) will be randomized into two groups. In the first group, RCUI will be performed according to current standards. In the second group, an anti-adhesive preparation with hyaluronic acid (Hyalobarrier gel Endo) will be applied to the uterine cavity at the end of the RCUI procedure. Eight to twelve weeks after the operation, the occurrence of adhesions will be evaluated by ultrasound examination and diagnostic hysteroscopy (if adhesions will be detected, they will be disrupted). The study will also include the completion of a questionnaire in terms of the frequency and strength of the menstrual cycle. The presence of adhesions will be assessed according to The American Fertility Society (AFS).

Methodology Only patients who sign informed consent will be included. Patients after a miscarriage in the 2nd trimester of pregnancy who need to perform an instrumental revision of the uterine cavity (RCUI, revisio cavi uteri instrumentalis) will be randomized into two groups. In the first group, RCUI will be performed according to current standards. In the second group, an anti-adhesive preparation with hyaluronic acid (Hyalobarrier gel Endo) will be applied to the uterine cavity at the end of the RCUI procedure. Eight to twelve weeks after the operation, the occurrence of adhesions will be evaluated by ultrasound examination and diagnostic hysteroscopy (if adhesions will be detected, they will be disrupted). The study will also include the completion of a questionnaire in terms of the frequency and strength of the menstrual cycle. The presence of adhesions will be assessed according to The American Fertility Society (AFS).

Expected number of enrolled subjects: a total of 200 patients, 100 in each branch Entry criteria: Adult (18 to 40 years old) women with a wish for future pregnancy, abortion in the 2nd trimester of pregnancy (over 12 weeks of pregnancy) with instrumental revision of the uterine cavity (RCUI), signed informed consent

Exclusion criteria: age below 18 years, age over 40 years, history of previous uterine surgery (myomectomy, resection of the intrauterine septum, disruption of intrauterine adhesions), suspicion of molar pregnancy, signs of pelvic infection, disagreement with participation in the study

Primary goals of the project:

1. determination of the frequency of intrauterine adhesions in women who underwent instrumental revision of the uterine cavity (RCUI, revisio cavi uteri instrumentalis) after abortion in the 2nd trimester of pregnancy
2. to determine whether the application of an antiadhesive agent with hyaluronic acid has an effect on the frequency of intrauterine adhesions after this procedure

A similar prospective randomized multicenter study investigating the relationship of intrauterine adhesions using an intrauterine gel with hyaluronic acid was published in 2017 by Hooker. Patients were enrolled in the study up to the 14th week of pregnancy. The incidence of intrauterine adhesions was statistically lower in the hyaluronic acid group compared to the no treatment group (13% vs. 30.6%, RR 0.43, 95% CI 0.22-0.83, p 0.013). However, this study investigated RCUI in the first trimester of pregnancy. Our study is to our knowledge the first with a focus on the second trimester RCUI.

Secondary goals of the project:

1. number of pregnancies (pregnancy rate) in the period of 24 months after RCUI in both groups
2. number of term pregnancies in the 24 months after RCUI in both groups

Inclusion Criteria:

• Adult (18 to 40 years) women with a wish for future pregnancy
• abortion in the 2nd trimester of pregnancy (over 12 weeks of pregnancy) with instrumental revision of the uterine cavity (RCUI)
• signed informed consent

Exclusion Criteria:

• age below 18 years, age over 40 years
• history of previous uterine surgery (myomectomy, resection of the intrauterine septum, disruption of intrauterine adhesions)
• suspected molar pregnancy
• signs of pelvic infection
• disagreement with participation in the study

Participant will not be informed about usage of hyalobarier gel or not. Care provider - at the time of RCUI the surgeon will know from randomisation if apply the gel or not. The investigator performing evaluation of adhesions by hysteroscopy will be blinded to the arm which the participants belong to.