A study of correlation of antenatal uterine scar thickness by transabdominal ultrasound with intraoperative lower uterine segment scar grading in elective repeat cesarean delivery

Haripriya Vedantham, Nandini Joshi Nee Jahagirdar, Ramadevi N., Vasundhara Kamineni, Sarada Saranu


Background: Caesarean section (CS) is the most common obstetric surgery performed world-wide. The objective of this study was to correlate the antenatal sonographic lower uterine segment (LUS) scar thickness in women with previous one cesarean section with intra operative LUS scar grading.

Methods: A Prospective observational study was conducted from December 2014 to November 2015. In a tertiary care center. 200 pregnant women from ANC clinic with previous one LSCS were recruited. Transabdominal USG done between 36-38 weeks. LUS thickness was measured from bladder wall-myometrium interphase and myometrium-chorioamniotic membrane inter phase. Intraoperative grading of LUS scar was done. Based on grading of scar participants were assigned into scar dehiscence group (grade III and IV LUS scar) and non-dehiscence group (Grade I and II LUS scar).

Results: Mean LUS thickness was 3.41±0.623 mm (range: 2-7 mm). Mean LUS thickness in the scar dehiscence group and non-dehiscence group was 2.98±0.55 mm and 3.48±0.60 mm (P value < 0.05) respectively. A cut off value of 3.5 mm was derived from ROC with sensitivity, specificity, positive and negative predictive value of 92.6%, 54.3%, 24.0%, 97.8%, respectively. The present study reported 27 (13.5%) cases of scar dehiscence.

Conclusions: Ultra-sonographic evaluation of LUS thickness correlated significantly with intraoperative LUS appearance. USG evaluation of LUS can be used as a screening test to predict the LUS scar integrity. Risk of dehiscence is increased in women with thin LUS i.e. sonographic LUS thickness of < 3.5 mm and needs to be further evaluated. Women with previous one LSCS with thick LUS i.e. sonographic LUS thickness of > 3.5 mm, can be counselled regarding TOLAC if not contraindicated.


Elective repeat caesarean delivery, Grades of scar, Lower uterine segment measurement, Scar dehiscence, Scar thickness, Trial of labor after caesarean

Full Text:



Gibbons L, Belizán JM, Lauer JA, Betrán AP, Merialdi M, Althabe F. The global numbers and costs of additionally needed and unnecessary caesarean sections performed per year: overuse as a barrier to universal coverage. World Health Report. 2010:30.

World Health Organization. Statement on caesarean section rates, 2015. Available at /publications/ maternal_perinatal_ health/cs-statement/en/.

Choudhury CR. Caesarean births: The Indian Scenario. Population Association of America; 2008:1-18.

Shanti S. Rising rate of caesarean section - a year review. J Nobel Med College. 2012;1:2.

Haider G, Zehra N, Munir AA, Haider A. Frequency and indications of cesarean section in atertiary care hospital. Pak J Med Sci. 2009;25(5):791-6.

Mozurkewich EL, Hulton EK. Elective repeat cesarean delivery versus trial of labor: a meta-analysis of the literature from 1989 to 1999. Am J Obstet Gynecol. 2000;183:187-97.

ACOG Practice bulletin no. 115: Vaginal birth after previous cesarean delivery. Obstet Gynecol. 2010;116(2Pt 1):450-63.

Zelop CM, Shipp TD, Repke JT, Cohen A, Caughey AB, Lieberman E. Uterine rupture during induced or augmented labor in gravid women with one prior caesarean delivery. Am J. Obstet Gynecol. 1999;181:882-6.

Fukuda M, Fukuda K, Mochizuki M. Examination of previous caesarean section scars by ultrasound. Arch Gynecol Obstet. 1988;243:221-4.

Rozenberg P, Goffinet F, Phillippe HJ, Nisand I. Ultrasonographic measurement of lower uterine segment to assess risk of defects of scarred uterus. Lancet. 1996;347:281-4.

Rozenberg P, Goffinet F, Philippe HJ, Nisand I. Thickness of the lower uterine segment: its influence in the management of patients with previous caesarean sections. Eur J Obstet Gynecol Reprod Biol. 1999;87:39-45.

Cheung VY. Sonographic measurement of the lower uterine segment thickness in women with previous caesarean section. J Obstet Gynaecol Can. 2005;27:674-81.

Qureshi B, Inafuku K, Oshima K, Masamoto H and Kanazawa K. Ultrasonographic evaluation of lower uterine segment to predict the integrity and quality of cesarean scar during pregnancy: A prospective study. Tohoku J Exp Med. 1997;183(1):55-65.

Hirobumi A, Akihito N, Gen I, Shyunji S, Tsotumu A. Prediction of uterine dehiscence by measuring lower uterine segment thickness prior to the onset of labor. J Nippon Med Sch. 2000;67(5):352-8.

Araki T, Inooka H. The diagnostic value of ultrasonotomography with reference to previous cesarean section scars during full term pregnancy. Acta Obstet Gynecol Scand. 1982; 34: 738-44.

Jastrow N, Chaillet N, Roberge S, Morency AM, Lacasse Y, Bujold E. Sonographic lower uterine segment thickness and risk of uterine scar defect: a systematic review. J ObstetGynaecol Can 2010; 4: 321-7.

Kushtagi P, Garepalli S. Sonographic assessment of lower uterine segment at term in women with previous cesarean delivery. Arch Gynecol Obstet. 2011;283(3):455-9.

Sen S, Malik S, Salhan S. Ultrasonographic evaluation of lower uterine segment thickness in patients of previous cesareansection. Int J Gynaecol Obstet. 2004;87(3):215-9.

Asakura H, Nakai A, Ishikawa G, Suzuki S, Araki T. Prediction of uterine dehiscence by measuring lower uterine segment thickness prior to the onset of labor: evaluation by transvaginal ultrasonography. J Nippon Med Sch. 2000;67(5):352-6.