Operative site infection remains the most common complication after performing a gynecological procedure, and has a great implication in the morbidity and mortality of patients. Gynecological procedures, including laparoscopic hysterectomy, represent a unique challenge due to the amount of microorganisms found at the skin level of the vagina or the endocervix.

However, there is no clear evidence that the complication decreases with the use of postoperative antibiotics.

With the completion of this study, a multicentre triple-blind controlled randomized controlled trial is intended to determine the behavior of the application of this intervention.

Patients who attend an outpatient clinic with benign pathology will be selected, in which indication of laparoscopic hysterectomy, consents are completed and research content is widely explained. Prior to surgery, the sample is taken for a gram of vaginal discharge and in the post-surgical phase delivery of the medication will be performed. Follow-up will be carried out by surgical control and by telephone.

The investigator intend to find that with the prophylaxis not only of presurgical cephalosporin, but with the formulation of metronidazole ovules in the postoperative, the incidence of laparoscopic post-hysterectomy vaginal abscess and cellulitis of cuff is reduced.

The development of the project will be carried out in the facilities of the Prado clinic in the city of Medellín and the Comfamily Clinic in the city of Pereira. Initially to the participants who attend by external consultation for assessment by the laparoscopic gynecology group that are candidates to perform a laparoscopic hysterectomy, they will be given general information about the research in development and its possible participation. Later on the day of surgery in the preparation room and before receiving any medication, The assigned investigator as assistant to the surgery will explain in detail the protocol of the investigation, the commitments acquired by the participant and the possibilities of withdrawal of the same, you will obtain the signature and trace of the informed consent. With the aim of not delaying the 7 am surgical program, a weekly resident will be assigned to inform and fill out the forms of the first patients scheduled for hysterectomy.

Advance by means of a table of random numbers generated in EPIDAT and that is hidden for the researcher. Participants will be assigned to one of the 2 groups, the intervention group will receive the treatment scheme with metronidazole 500mg ovules every 12 hours for 5 days and the control group will receive a placebo.

After this in the surgery room and with the participants under general anesthesia, the sample will be taken for gram of vaginal discharge, previous marking of the plate, with the initials of names and surnames and the patient's identification number, With the use of a speculum and applicator the sample will be taken in the sack bottoms or vaginal walls, which will be sent to the Prolab laboratory in the city of Medellín and the laboratory of the Comfamily clinic in the city of Pereira. for its processing, standardization will be made prior to reading it with the staff of both laboratories.

For the diagnosis of bacterial vaginosis, the Nugent criteria will be used. In this method, the morphotypes corresponding to large Gram-positive bacilli, small Gram-negative bacilli and curved variable Gram bacilli are quantified. And a value is assigned according to the findings. The interpretation of the results is numerical based on the score obtained by adding the crosses of the morphotypes of the bacteria present in the vaginal discharge: 7 or more points are diagnostic of bacterial vaginosis, from 4 to 6 points is considered intermediate and from 0 to 3 is considered normal.

At the end of the surgical procedure, the investigator will complete the completion of Annex 1, will go to the pharmaceutical service where he will request the corresponding product to the patient. The pharmacy staff will verify the assigned number in the randomization table and deliver the medication and the resident will take it to the recovery room with its respective formula.

The assigned investigator will conduct a telephone interview 7 days after the procedure to assess the post-surgical evolution, will be questioned about the presence of symptoms that may be related to an infectious process. Between 10-15 days of the surgical procedure, the gynecologist will perform the post-surgical review in an outpatient clinic to assess the evolution of the patient and re-evaluate the result of the pathology. The Gram result of vaginal discharge, the pathology and the evolution note made by the surgeon will be reviewed with the aim of detecting any diagnosed complication. Finally, 30 days after the procedure, the last telephone follow-up will be performed to detect the presence of any infection. of the operative site.

Inclusion Criteria:

• Patients between 18 and 55 years old scheduled for laparoscopic hysterectomy for benign pathology in the two centers linked to the study (Clínica del Prado and Pereira community clinic), who have been informed of their participation in the study and who have signed informed consent.
• Patients who are able to communicate by telephone and answer questions

Exclusion Criteria:

• Patients who are participating in another study of antibiotic treatment.
• Patients who have a known allergy to imidazole medications.
• Patients with current diagnosis of bacterial vaginosis.
• Patients with current treatment or 30 days prior to surgery for bacterial vaginosis or antibiotic treatment for another pathology.
• Patients who do not reside in Medellín or in its nearby municipalities and can not attend the scheduled evaluation.