Scar Ring Formation Due To Lower Segment Caesarean Sections

Author Information

Wagh PT*, Parulekar SV**
(* Senior Resident, ** Professor and Head, Department of Obstetrics and Gynecology,  Seth G S Medical college and KEM Hospital, Mumbai, India.) 


Cesarean section scars may cause difficulties during future pregnancies and any surgery the patient has to undergo. We present a case report of an unusual problem during a first trimester medical termination of pregnancy (MTP) due to previous cesarean section scars.


Some of the commonly known and faced long term complications due to lower segment cesarean section (LSCS) are uterine scar dehiscence or rupture and intra-abdominal adhesions.[1,2] Other problems like scar endometriosis, adherent placenta, and scar ectopic pregnancy may also be seen.[1,2] In our case, previous caesarean section scar had formed an incomplete ring like constriction around the isthmus of the uterus, which posed difficulty during cervical dilatation and curettage.

Case Report

A 35 year old gravida 3, para 2, living 2 patient with previous 2 LSCS came to us with 7 weeks intrauterine gestation for medical termination of pregnancy. She gave a history of receiving 15-S-15-methyl PGF2alpha intramuscularly followed by an attempt at dilatation and curettage in a private hospital, which had to be abandoned as the cervix could not be dilated. Then tablet misoprost 800 µg was kept per rectally but that also failed to cause any bleeding or cervical dilatation. Hence she was referred to our hospital.

Her medical and surgical history was not contributory. Her last cesarean section had been performed 2.5 years ago. Her general and systemic examination revealed no abnormality. Abdominal examination showed a Pfannenstiel scar and other normal findings. On per vaginal examination the uterus was 7-8 weeks' size, acutely retroflexed and retroverted (cochleate). The fornices were nontender, without any mass. The results of her investigations for fitness for anesthesia were normal. Due to the risk of uterine rupture, we decided not to use pre-procedure misoprostol for cervical dilatation in this patient. She was put in lithotomy position under general anesthesia. the cervix was held with vulsellum to give outward and upward traction to straighten the axis of uterus, uterine sounding was done and dilatation of cervix with Hegar’s dilators was done. Dilatation posed difficulty as we had to negotiate the dilators first in horizontal and then upward and backward direction. There was resistance at two levels – the first at the level of the internal os, and the other about 1 cm above it. Cervical dilatation to 8 mm could be achieved with difficulty. Suction evacuation was performed and check curettage was done. During check curettage, a ring like ridge was felt above the level of the cervix anteriorly (in the area where an LSCS scar would be expected to be present) and laterally. It was thought to be due to previous two caesarean sections that the patient had undergone. The patient made an uneventful recovery after the procedure. After 2 days of procedure we performed ultrasonography on the patient to check for the ring like constriction that was felt during surgery and it was found to be LSCS scar.

Figure 1. Pelvic ultrasonogram showing thickened LSCS scar.


Difficulty may be encountered during rapid dilatation of the cervix for first trimester MTP.[3] It may be due to nulliparity or no vaginal delivery in the past in a parous woman (due to deliveries being by LSCS). Scar formation is a process of healing of wounds, including surgical wounds. The lower uterine segment contains more fibrous tissue than smooth muscle, and its incisions heal with fibrosis. Usually the LSCS scar is of the same thickness as the wall of the lower segment when the healing is good, or thinner if the healing is not good due to any reason. A scar thicker than the wall of the lower segment has not been reported in literature so far. In our case there was a scar in the lower segment that produced a ridge projecting into the cavity of the lower segment. That might be explained by presence of two scars close to each other, though such an occurrence has not been reported so far, even in cases with more than two previous LSCS. Another unusual feature in this case was presence of the thick scar on the lateral aspects of the lower segment too. It might have been due to extension of the lower segment incision onto the lateral walls, possibly to overcome difficulty in delivery of the baby. Presence of thick scar tissue on three sides of the lower segment must have caused constriction of the lower segment, which would not yield during rapid dilatation of the cervix. Such a scar may be seen during antenatal ultrasonography, so that difficulty during dilatation for MTP can be anticipated.[4] Cervical resistance to rapid dilatation may be prevented by prior use of misoprostol in a woman who has not delivered any baby vaginally in the past.[5] However there is no method of avoiding difficulty due to a constricting scar in the lower segment during performance of the procedure, and it has to be dealt with if it occurs.

  1. Hakim-Elahi E, Tovell HM, Burnhill MS. Complications of first-trimester abortion: a report of 170,000 cases. Obstet Gynecol 1990; 76:129-35.
  2. Ferris LE, McMain-Klein M, Colodny N, Fellows GF, J Lamont J. Factors associated with immediate abortion complications. CMAJ 1996; 154:1677-1685.
  3. Kaunitz AM, Rovira EZ, Grimes DA, Schulz KF. Abortions that fail. Obstet Gynecol 1985; 66:533-37.
  4. Basic E, Basic-Cetkovic V, Kozaric H, Rama1 A. ULTRASOUND EVALUATION OF UTERINE SCAR AFTER CESAREAN SECTION. Acta Inform Med. 2012 Sep; 20(3): 149–153.
  5. Schulz KF, Grimes DA, Cates W Jr. Measures to prevent cervical injury during suction curettage abortion. Lancet 1983; 1:1182-85.

Wagh PT, Parulekar SV. Scar Ring Formation Due To Lower Segment Caesarean Sections. JPGO 2015. Volume 3 No. 5. Available from: