Fear of Uterine Scar Dehiscence or Rupture in Women with Previous Three or More Lower Uterine Segment Cesarean Section- A Retrospective Observational Study
Muna Mubarak Al Badi, Nishat Fatemaσ*, Neeru Vinod Aroraρ &.. Fatma Majid Al AbriѠ
Objective: To evaluate the association of uterine scar dehiscence or ruptures with the increasing order of cesarean delivery and to counsel regarding these dreadful complications to women with previous multiple repeat cesarean sections.
Materials and Methods: We carried out a retrospective observational study at Ibri Regional Hospital Oman from between January 2009 and December 2013. 287 women who underwent cesarean section (CS) for two or more times were studied concerning the timing of current cesarean section, adhesions, condition lower uterine segment, dehiscence of previous scar or rupture, any injuries to the internal organs, blood loss and postoperative complications. Fetal outcomes included gestational age at birth, birth weight APGAR scores, neonatal intensive care unit admissions.
Results: Maternal and neonatal outcomes were presented and compared between two Groups. A significant increase was observed in the presence of intra-abdominal adhesion in proportion to the number of CS (P = 0.001)
Statistical difference was observed among the groups concerning the perioperative estimated blood loss (P = 0.001) and the need for blood transfusion (P = <0.001).
There was no difference between the two groups the incidence of abnormal placental localization (placenta previa and placenta accrete) (P = 0.57). There was no significant difference among the groups regarding neonatal outcome. Both differed significantly regarding previous scar thickness (P = 0.05). Our result reported an incidence of scar dehiscence and ruptured among the study population of 1.7% and 0.3% respectively.
Conclusion: The key findings of this study included instances of intra-abdominal adhesions, the need for blood transfusions, postoperative complications, and duration of hospital stay increased among women with three or more previous cesarean sections (CSS) in comparison with women with two CSS. Our result revealed that in the Group 1 of the study, the frequency of the thinning of previous scar, scar dehiscence, and uterine rupture was more in comparison to Group 2 with two previous CSS. The overall incidence of scar dehiscence and rupture in our study population is similar with other studies. Women with a history of multiple repeat CS should be informed and educated about these possible complications before planning future pregnancies.
Author ασρѠ: Department of Obstetrics & Gynaecology, Ibri Regional Hospital, Ministry of Health, Sultanate of Oman Ibri Regional Hospital, Ibri. P.O Box 352 Sultanate of Oman.
In modern obstetric practice, the introduction of lower segment cesarean section (CS) Delivery have led to the decrease in incidences of maternal and neonatal morbidities. Cesarean section is one of the most common obstetric surgical procedures performed all over the world 1. Data analyzed from 121 countries revealed that between 1990 and 2014, the CS rate increased by around 12.4% (from 6.7% to 19.1%) globally. The highest rate of CS is found in Latin America and the Caribbean (19.4%), followed by Asia (15.1%), Oceania (14.1%), Europe (13.8 %), North America (10%), and Africa (4.5%) 2,3.
Women requiring multiple repeats CS is an increasing trend, particularly in Middle Eastern countries where permanent sterilization methods are not readily acceptable and Social attitudes encourage having a large family. In other developed countries, pregnancy since three CSS is usually discouraged, although there is no clear evidence in the literature to validate this practice 4,5.
However, it is important to note that cesarean delivery is not a risk-free procedure. Repeat CSs are associated with an increased incidence of serious complications such as morbid intra-abdominal adhesions, bladder injury, placenta previa, abnormally adherent placenta, scar dehiscence, or uterine rupture. The risk of neonatal complications and long-term morbidities also increases with multiple CSS 6.
Uterine scar dehiscence and rupture are feared complications of CS. The incidence of uterine scar dehiscence reported in literature is around 0.2% to 4.3% of all pregnancies with a previous history of CS that might cause scar rupture. Furthermore, the scar rupture rate was found to be 0.4 to 0.6% 7,8.
The objective of our study is to evaluate the association of uterine scar dehiscence or rupture with the increasing instances of cesarean delivery and to offer counsel regarding these dreadful complications to women with previous multiple repeat CS.
We conducted a retrospective observational study at Ibri Regional Hospital Oman, of women with previous (three or more) repeat cesarean sections (Group 1) between January 2009 and December 2013. The control group also included women with two previous cesarean sections (Group 2).
Group 1 (n=137) = Previous 3 CS (n = 102)
Previous 4 CS (n = 27)
Previous 5 CS (n = 08)
Group 2 = Previous 2 CS (n = 150)
Data were collected from delivery registers and electronic medical record system. Ethical approval for this study was obtained from the research committee in the Al Dhahirah region (Ref number: MH/DGHS/DG/DG/589/16).
Inclusion criteria: We included all women with previous history of three or more cesarean section (CS), who were compared with Group 2 including women with two previous CSS.
Exclusion criteria included primary CS, one previous CS, multiple gestations, previous history of any other abdominal and pelvic surgery other than CS, and women who had previous classical CS.
The maternal clinical characteristics, demo graphic data, and outcomes were analyzed. The data related to neonatal outcome including birth weight, Apgar scores, and instances of admission to Neonatal Intensive Care Unit (NICU) were evaluated.
According to the hospital protocol, the timing for elective CS was determined to be 38–39 weeks’ gestation under regional or general anesthesia. At least sixty minutes before the CS, 2 grams of Cefazoline was administered intravenously to all patients along with other pre-medications. If the patient was allergic to Cephalosporins, Inj. Ampicillin (2 gram) was administered.
On the 2nd postoperative day, full blood count (FBC) was measured, and wound dressing was removed on the 3rd postoperative day. All patients received prophylactic low molecular weight heparin (LMWH) for five days post the operation as per hospital protocol. Uncomplicated cases were discharged on the 4th postoperative day.
For this study, visual estimation of the lower uterine segment’s condition during CS is measured as follows:
- Thinned scar is defined as a thin lower uterine segment, with thickness less than 3 mm during the intraoperative observation
- Scar dehiscence is defined as loss of continuity of myometrium, but the overlying serosa is intact through which either membranes are bulging, or parts of the baby can be visualized
- Uterine rupture is described as full thickness tear of the uterine wall including serosa, with an intraoperative finding of fetal parts within the abdominal cavity
- Adhesion is defined as a fusion of anterior uterine surface and anterior abdominal Wall with omentum, bladder, bowel, or parietal peritoneum.
- Placenta previa is defined as placenta covering the internal cervical os, completely or Partially, as per ultrasonography (USG) performed after 32 weeks’ gestation.
- Placenta accreta is defined as when the placenta invades the myometrium and is diagnosed with the color doppler USG, magnetic resonance imaging (MRI), and a histopathological specimen of the uterus in cases of hysterectomy.
Blood transfusion was provided i by the excessive bleeding during surgery or postoperatively if hemoglobin is less than 8.5 gm/dl as per hospital protocol.
For all statistical analysis, the Statistical Package for the Social Sciences software version 23.0 (SPSS Mac IOS) was employed. For the demographic data, descriptive analysis was performed. Continuous variables were represented as minimum, maximum, median, and mean ± standard deviation. Categorical variables were compared by the Pearson’s chi-squared test. A P-value less than 0.05 (2-sided) was considered as statistically significant.
In the study, out of 287 patients, 150 patients had two cesarean sections (CSS) before the current pregnancy, 102 had three, 27 had four, and eight cases had five previous CSS.
Maternal characteristics of the cesarean groups have been compared in Table 1.
The mean maternal age was 36±3.5 years in Group 1 (three or more previous CSS) in comparison to 34.0 ±4.1 years in the Group 2 with two previous CSS (P = < 0.001).
Mean parity was found to be significantly different among Group 1 (4±1.8) and 2 (3±1.7) (P = <0.001).
Gestational age at birth was not significantly different between Group 1 and 2 (p = 0.40).
Regarding frequency of emergency and elective CS between the two groups, we observed that in the study group, the frequency of emergency CS (62%) is higher than in the control group (38%) (P = 0.03). Instances of hospital stay more than four days was significantly different between Group 1 (63%) and 2 (37%) (P = 0.01).
Maternal and neonatal outcomes were presented and compared between two groups in Table 2. A significant increase was observed in the presence of intra-abdominal adhesion in proportion to the number of CS (P = 0.001)
Statistical difference was observed among the groups concerning the perioperative estimated blood loss (P = 0.001) and the need for blood transfusion (P = <0.001).
There was no difference between the two groups regarding the incidence of abnormal placental localization (placenta previa and placenta accrete) (P = 0.57). One patient with three previous CSS had placenta accreta, and that patient required an emergency hysterectomy due to atonic bleeding.
No significant difference was observed among the groups about other perioperative complications such as bladder or bowel injury, hematoma formation, and extension of uterine incision (P = 0.71)
Five women required post-operative ICU admission. Among them, there were three cases of three previous CSS, one case of four previous CSS, and one of five previous CSS. No patient with two previous CS required admission to the ICU (P = 0.02). The indications for the cases of ICU admissions were anesthesia complications in two women, pulmonary edema in one, severe hemorrhage due to placenta accreta in one, and severe preeclampsia in one.
There were no maternal deaths in our study sample, but the number of study population is small to address the issue of mortality rates.
Statistically significant differences were identified among the groups regarding the postoperative complications (P=0.03). In Group 1, three or more previous CSS, 12 cases were observed to have postoperative complications: four patient had urinary tract infection (UTI), one patient developed paralytic ileus, four of them had a fever, and two of them were observed to have surgical wound infections. In Group 2, two previous CSS, one woman had UTI, one patient developed fever, and two patients developed surgical wound infections.
There was no significant difference among the groups regarding neonatal outcome. There were no instances of fetal or neonatal death in the study group or control group. No statistical significance was found between the Apgar scores and number of previous CSS. Babies of these two groups did not differ concerning birth weights (P = 0.87). Admissions to neonatal intensive care unit were also observed to be similar in both groups (P = 0.71) (Table 2).
Both groups differed significantly regarding previous scar thickness (P = 0.05) (Table 3). Our result reported an incidence of scar dehiscence and ruptured among the study population of 1.7% and 0.3% respectively.
Forty-seven (34%) patients in the group 1 were found to have thin scars (less than 3mm Intraoperative), four (2.9%) cases had scar dehiscence, and one was found with scar rupture (0.7%). Among the scar dehiscence cases, two patients had three previous CSS, one patient had four previous CSS, and another had five previous CSS. The single instance of scar rupture was observed in the case of a woman who had a history of three previous CSS.
Although multiple repeated cesarean section (CS) is associated with increased maternal and fetal complications when compared to vaginal birth or primary CS, but the frequency of repeat CSS is increasing with associated complications due to social and cultural expectations for larger families, especially in the Arab countries.
Previous studies have presented disparate results to establish the consequences of multiple repeated CSS on future pregnancies 9.
After caesarean delivery, intra-abdominal adhesions are frequent, and the increasing rate of intra-abdominal adhesions is directly related to the higher number of instances of CS. In literature, overall intra-abdominal adhesion rates are mentioned to be 12–46% in patients with two previous CSS and 26–75% in those who have undergone there or more previous CSS 10.
A retrospective study of 308 cases with four or more previous CSS found that the rate of adhesion was 54%, in comparison to the women with two and three previous caesarean sections; only 15% had dense intra-abdominal adhesions (P = <. 001) 11.
Our data revealed that adhesions increased with the increasing number of CSS (0.001); other researchers who have been mentioned above have reported similar results.
In a study of 120 patients, Uyanikoglu et al. reported that women with two previous CSS required less blood transfusion in comparison to patients with two or more previous CSS(P = 0.018). They tried to explain the reason behind the high rate of blood transfusion in those women to be due to multiparity, atonic uterus, abnormal placental localization, and multiple gestations 10.
The result of our study is consistent with the study above. In Group 1, women with three or more previous CSS, 77% of patients received blood transfusion whereas only 23% cases of women with two previous CSS received the blood transfusion (P = <0.001).
Previous studies have mentioned that women with two or more previous CSS face an increased risk of placenta praevia and placenta accreta in their future pregnancy. The risk of placenta previa, especially with placenta accreta after one CS, is shown to be 1%, and this risk increases to 2.8% after three or more CSS 1,10.
The incidence of placenta praevia increases if the patient has a history of a previous uterine scar and the hypothesis is, damage to the endometrium and myometrium predisposes one to low implantation and placenta praevia in a subsequent pregnancy. This impaired decidualization at the site of the scar enables the trophoblast to invade the myometrium, preventing placental migration away from the cervix, resulting in placenta previa. Previous studies have mentioned that there is a linear correlation between the risk of cesarean hysterectomy in cases of placenta praevia or accreta and the number of previous CS 1. We found six (46%) cases of placenta praevia and only one case with placenta accreta in Group 1 including women with three and more previous CSS, and no statistical significance was observed in comparison to Group 1 including women with two previous CSS (P = 0.57). The patient who had placenta accreta had to get cesarean hysterectomy done due to an atonic uterus and uncontrolled bleeding. However, our results could probably be attributed to the smaller size of the study that limits the chances of assessing the risk significantly.
Regarding intraoperative complications, on review of the literature, a study of 301 patients reported only two patients with accidental urinary bladder injuries during CS due to the dense adhesions in the case of women with two or more previous CSS. Furthermore, in the same study, no cases with bowel injury were reported. Kaplanoglu et al. observed that women with a history of four CS depicted a higher incidence of bladder injury12,13.
In another retrospective study of 308 patients, only one patient with repeat CS had a bowel injury where the abdominal cavity was opened through a midline incision. Other studies also mentioned that bowel injury is less frequent as utero-intestinal adhesions are not common 11.
In our study, on comparing the two groups, we did not observe a significant difference with respect to such intraoperative complications (P = 0.71).
Uygur et al. reported that postoperative complications such as UTI, pyrexia, wound infections are not related to the number of previous CSS 12.
Another study revealed that women with three or more previous CS faced a higher risk of postoperative pyrexia due to extensive adhesions, more tissue handling, and operative time. The researchers didn’t observe any difference about wound infection comparing previous multiple CS groups 10.
The results of our study showed statistically significant differences between the groups in terms of the postoperative complications (P = 0.03). In Group 1, with three or more previous CSS, 75% Cases were observed to have postoperative complications: four patients had urinary tract infection (UTI), one patient developed paralytic ileus, four cases had a fever, and two patients were observed with surgical wound infections. In Group 2, women with two previous CSS, 25% patients were identified with postoperative complications: one case had UTI, one patient developed fever, and two patients had surgical wound infections.
Uterine scar dehiscence and rupture are feared complications of CS. The incidence of uterine scar dehiscence reported in literature is around 0.2% to 4.3% of all pregnancies with a previous history of CS that might cause scar rupture, and the scar rupture rate is 0.4 to 0.6% after previous CS 7,14.
Previous studies showed that the number of previous CSS does not affect the incidence of scar dehiscence. Moreover, certain studies in the literature did not find any statistically significant increase in uterine scar rupture along with an increased number of cesarean deliveries 2,15.
Our study’s result revealed that both groups differed significantly regarding previous scar thickness (P = 0.05) (Table 3). Our result reported an incidence of scar dehiscence and ruptured among the study population of 1.7% and 0.3% respectively which is consistence with intern ational figure 7,8.
Forty-seven (34%) patients in the group 1 were found to have thin scars (less than 3mm Intraoperative), four (2.9%) cases had scar dehiscence, and one (0.7%) was found to have scar rupture. Among the instances of scar dehiscence, two patients had three previous CSs, one patient had previous four CSS, and another had five previous CSS. The one patient who had scar rupture had the history of three previous CSS.
On the other hand, in Group 2, women with two previous CSS, only one (0.7%) case was found with scar dehiscence and none of the patients’ experienced the uterine rupture.
Regarding neonatal outcomes, in two large retrospective studies, Qublan et al. and Ozcan et al. reported that in patients with a history of repeat multiple CS, the incidences of low Apgar score, NICU admission, and preterm birth were similar in all groups 16,17.
The results of our study also could not establish any significant difference regarding neonatal outcomes between the two groups, and the results were consistent with the studies above.
The key findings of this study included instances of intra-abdominal adhesions, the need for blood transfusions, postoperative complications, and duration of hospital stay increased among women with three or more previous cesarean sections in comparison with women with two previous CSS. Our result revealed that in the Group 1 of the study, the frequency of thinning of the previous scar, scar dehiscence, and the uterine Rupture was more in comparison to Group 2 with two previous CSS. The incidence of scar dehiscence and rupture in our study population is similar with previous studies.
Women with a history of multiple repeat CS should be informed and educated about these possible complications before planning future pregnancies.
However, our study results are limited by the fact that it is a retrospective study. Moreover, in our study, the number of women with four and five previous CSS was small in comparison to the number of women with two and three previous CSS. Subjective assessment of certain parameters such as adhesions and scar thickness is also a limitation about reliability. This is partially due to the subjective assessment and partially due to the widely variable experience and expertise among the surgeons operating on such cases. More prospective studies are required to investigate these points related to multiple repeat CS.
Source(s) of support: Nil
Conflicting Interest: None declared
We would like to thank, our colleagues- Dr.Noureen Waleem, Dr Kavita Ukesh, Dr.Hira Saleem, Dr.Meena Kumari, Dr. Adeela Ahmed, Dr.Noheen Rashid, Dr.Mahin Rahman, and Dr.Ruksana Rashid, for helping us in Data collection process.
- Lynch CM, Kearney R, Turner MJ. Maternal morbidity after elective repeat caesarean section after two or more previous procedures. Eur J Obstet Gynecol Reprod Biol. 2003; 106(1):10-13.http://www.ncbi.nlm.nih.gov/pubmed/12475574. Accessed December 12, 2016.
- Yaman Tunc S, Agacayak E, Sak S, et al. Multiple repeat caesarean deliveries: do they increase maternal and neonatal morbidity? J Matern Neonatal Med. May 2016:1-6. doi:10.1080/14767058.2016.1183638.
- Martin JA, Hamilton BE, Sutton PD, Ventura SJ, Menacker F, Kirmeyer S. Births: final data for 2004. Natl Vital Stat Rep. 2006;55(1):1-101.http://www.ncbi.nlm.nih.gov/pubmed/17051727. Accessed December 12, 2016.
- Makoha FW, Felimban HM, Fathuddien MA, Roomi F, Ghabra T. Multiple cesarean section morbidity. Int J Gynaecol Obstet. 2004; 87(3):227-232.doi:10.1016/j.ijgo.2004.08.01.
- Alnoman A, El-Khatib Z, M S Almrstani A, Walker M, El-Chaar D. Case series of multiple repeat caesarean sections: operative, maternal, and neonatal outcome. J Matern Neonatal Med. 2016;29(12):1972-1976. doi:10.3109/14767058.2015.1071347.
- Clark EAS, Silver RM. Long-term maternal morbidity associated with repeat cesarean delivery. Am J Obstet Gynecol. 2011;205(6):S2-S10.doi:10.1016/j.ajog.2011.09.028.
- Baron J, Weintraub AY, Eshkoli T, Hershkovitz R, Sheiner E. The consequences of previous uterine scar dehiscence and cesarean delivery on subsequent births. Int J Gynaecol Obstet. 2014;126(2):120-122. doi:10.1016/j.ijgo.2014.02.022.
- Journal of Postgraduate Gynecology & Obstetrics: Multiple Cesarean Section Scar Dehiscences.http://www.jpgo.org/2014/09/multiple-cesarean-section-scar.html. Accessed September 9, 2017.
- Choudhary G, Patell M, Sulieman H. The effects of repeated caesarean sections on maternal and fetal outcomes. Saudi J Med Med Sci. 2015;3(1):44. doi:10.4103 1658-631 X.149676.
- Uyanikoglu H, Karahan MA, Turp AB, et al. Are multiple repeated cesarean sections really as safe? J Matern Neonatal Med. 2017;30 (4):482-485.doi:10.1080/14767058.2016.1175426.
- Rashid M, Rashid RS. Higher order repeat caesarean sections: how safe are five or more? BJOG An Int J Obstet Gynaecol. 2004;111 (10):1090-1094.doi:10.1111/j.1471-0528.2004.00244.x.
- Uygur D, Gun O, Kelekci S, Ozturk A, Ugur M, Mungan T. Multiple repeat caesarean section: is it safe? Eur J Obstet Gynecol Reprod Biol. 2005;119(2):171-175.doi:10.1016/j.ejogrb.2004.07.022.
- Bakacak SM, Bulbul M, Kaplanoglu D, Bakacak SM. Effect of Multiple Repeat Cesarean Sections on Maternal Morbidity: Data from Southeast Turkey. Med Sci Monit. 2015;21:1447-1453.doi:10.12659/MSM.893333.
- Samant PY PS. Journal of Postgraduate Gynecology and Obstetrics. J o Postgrad Gynecol Obstet. 2014;1(9). http://www. jpgo.org/2014/09/multiple-cesarean-section-scar.html. Accessed December 14, 2016.
- Soltan MH, Al Nuaim L, Khashoggi T, Chowdhury N, Kangave D, Adelusi B. Sequelae of repeat cesarean sections. Int J Gynaecol Obstet. 1996;52(2):127-132. http:// www.ncbi.nlm.nih.gov/pubmed/8855090. Accessed December 14, 2016.
- Qublan HS, Tahat Y. Multiple cesarean section. The impact on maternal and fetal outcome. Saudi Med J. 2006;27(2):210-214. http://www.ncbi.nlm.nih.gov/pubmed/16501678. Accessed December 15, 2016.
- Özcan S, Karayalçın R, Kanat Pektas M, et al. Multiple repeat cesarean delivery is associated with increased maternal morbidity irrespe- ctive of placenta accreata. Eur Rev Med Pharmacol Sci. 2015;19(11):1959-1963. http:// www.ncbi.nlm.nih.gov/pubmed/26125254. Accessed December 15, 2016.
Table 1: Maternal demographics and pregnancy characteristics
Group 1 Previous 3 or > CS: n (%)
Group 2 Previous 2 CS: n (%)
Age Mean ± SD
Parity Mean ± SD
Gestational age at delivery
Hospital stay 4 days
Table 2: Maternal and neonatal outcomes
Maternal and neonatal outcome
Previous 3 or > CS: n (%)
Previous 2 CS: n (%)
Abnormal lacental location
All data are expressed as n (%) unless as specified Percentages are expressed for Columns
Table 3: Previous Uterine Scar Condition