The present study showed an increased risk of relaparotomy following CD in twin gestations, pregnancies complicated by hypertensive disease or placenta previa and following urgent CS, and following CD in the second stage of delivery. There was no difference in the rate of relaparotomy between different hours of the day.
We excluded surgeries with placenta accreta because these operations are prone to bleeding complications and relaparotomy, and our goal was to analyze the more common CD’s. The rate of 0.26% of laparotomy following delivery reported in our study resembles the incidence of 0.2–1.04% relaparotomies, previously reported2–5,10−16.
As described in previous studies, pregnancies with placenta previa are scheduled for operations earlier than other elective CD, which may explain the significantly lower birthweight and lower gestational age in the relaparotomy group for this indication4,5. Pregnancies with placenta previa are prone to bleeding from the placental bed, and difficulties to control bleeding from the isthmus and upper cervical part17,18, leading to the significant risk for relaparotomy found in our study. In this study, multiple pregnancies were associated with increased risk of relaparotomy. The difficulty to adequately control bleeding in over-distended uterus may explain the increased risk of uterine atony and bleeding3,19. Late preterm delivery of multiple pregnancy is common and this explains the earlier gestational age and the lower birthweight found in the relaparotomy group following twins CD19. Since ART may result in higher rates of multiple pregnancies, this may explain the statistically significant association between ART and relaparotomy found in the univariate analysis.
Although obesity is associated with technically difficult CD, along with postpartum complications such as wound rupture 20, we did not find a significant risk for relaparotomy in overweight patients. Furthermore, BMI was significantly lower in the relaparotomy group.
Several studies reported an association between fetal gender and different complications of pregnancy 21, including increased risk of relaparotomy in pregnancies with female fetuses 2. Nevertheless, we did not find any correlation between relaparotomy and fetal gender.
Similar to previous studies 1,5, we found that hypertensive diseases of pregnancy were associated with a significant risk of relaparotomy. Ahmed et al found that the most common comorbidity in patients with relaparotomy was hypertensive disorders 22. It has been suggested that the main reason for this association is the coagulation disorders that may complicate severe hypertensive disorders23–25.
There are controversial reports regarding the association between previous CD to elevated risk of relaparotomy. Several studies reported an association between a history of previous CD and relaparotomy following a repeat CD 1,5 while others did not find such an association 3. We did not find such an association, nor between the interval between the CD’s and relaparotomy.
Previous studies reported that increased operative time increases the risk of relaparotomy 2,3. Contrary to that, we did not find such an association. Indeed, Rottenstreich et al reported that in repeated CD, prolonged operative time (defined as longer than the 90th percentile for each specific surgeon) is associated with adverse maternal complications such as post-operative blood transfusion, prolonged hospitalization, infections, and readmission, but they did not describe an association to relaparotomy 26.
Previous studies reported increased risk of relaparotomy following emergent CD10,11. These studies defined emergent CD as the non-elective CD. In the present study we divided the non-elective CD to emergent CD, and to urgent CD that included cases with immediate life threatening risk to the mother or the fetus. As expected, elective CD were significantly associated with lower risk of relaparotomy. However, there was no increased risk of relaparotomy following emergent CD, such as patients that were operated prior to a scheduled CD, but with no immediate risk of fetal or maternal compromise. We did find a significant increased risk in relaparotomy after urgent CD, with a 2-fold increase in the rate of relaparotomy in urgent CD performed during the second stage of labor. The duration of the second stage did not influence the risk of relaparotomy.
The median time of relaparotomies was 14 hour from delivery. Similar to that, Ashwal et al reported that the rate of relaparotomies during the first 24 h, first week and beyond it, following CD was 64.5, 22.6 and 12.9 %, respectively 10. Kessous et al also reported that most women (51.2%) underwent relaparotomy during the first 24 h after CD 5 and Akkurt et al described a mean interval between CD and relaparotomy of 15.7+/-3.2 hours 1. Patients with risk factors for relaparotomy should be carefully monitored during the first 24 hours following CD.
The leading cause of laparotomy following delivery in our study was bleeding. Similarly, most studies reported that the leading indication for relaparotomy were postpartum hemorrhage leading to hemodynamic shock 1–5,10−15,27. The etiology of hemorrhage was bleeding from uterine atony, bleeding from placental bed after operation for placenta previa, hemorrhage due to myomectomy performed during CD and hemorrhage from anterior abdominal wound dehiscence13. Other findings during relaparotomy included organ damage and foreign body, similar to cases reported before 2,14
Interestingly, in 12.5% of the cases there were no intraabdominal findings during relaparotomy. A previous report has found no findings in 60.7% of the patients 2.
Laparotomy following delivery increases the risk of maternal morbidity due to bleeding, coagulation disorders, requirement of blood products, infections; increases hospitalization days and creates a burden to the medical system. The most catastrophic complication is maternal death with previous reports ranging from 0 to12% 4,11–15,20,28. In our study, 12.5% developed disseminated intravascular coagulation and 17.2% of our patients were admitted to the intensive care unit. Fortunately, there were no cases of maternal mortality.
A third laparotomy was needed in 6.25% of our patients, lower than the 19.6% reported by Seal et al 11. Most cases both in our study and in previous studies were due to intraabdominal hemorrhage.
We acknowledge several limitations in our study. Our medical center is a tertiary referral hospital resulting in an increased rate of high risk pregnancies. Thus our results may not represent the numbers in most delivery wards. I order to overcome part of this limitation we excluded pregnancies with placenta accrete. The large number of CDs over many years in the present study results in a more accurate perspective regarding the risk factors and the characteristics of relaparotomies following CDs.