This Systematic review and meta-analysis was conducted to identify the pooled prevalence of SSI after cesarean section and associated factors in Ethiopia. We found high prevalence of SSI after cesarean section in Ethiopia with an overall prevalence of 9.72% (95%CI: 8.38, 11.05). This systematic review and meta-analysis reported a higher prevalence as it was compared with the sphere standard of CDC guidelines of SSI (which was 5%)[35].
SSI after cesarean section is considered as an indication of quality of health care service. However, it represented with high figure that make the quality of health care service to be questionable in Ethiopia. Although several endogenous risk factors are there, it can be possibly explained by that limited and ineffective implementation of evidence based SSI prevention strategies recommended by CDC may increase the problems.
This includes limited and ineffective administering of antimicrobials before 1hr of procedure, prolonged preoperative admission of patients, longer duration of procedures and inability to prevent obstetric complications (PROM, chorioamnionitis)[36]. It was also much higher than among studies conducted in Nova Scotia and New Zealand reports of SSI prevalence; 2.7% and 5.2% [37, 38]respectively.
This systematic review and meta-analysis was lower as compared with a reports from India (8.9 %,), England (9 %), Norway (9.1%) and Nigeria (9.6%)[39-42]. It was also much lower than from reports of Jordan (14.4%), Malaysia (18.8%), a systematic review from Sub-Saharan Africa (15.6%) and Egypt (16.7%) [8, 43-45]. Hence, application of evidence based strategies should be there, like timely administration of appropriately selected prophylactic antibiotics, use of a chlorhexidine-alcohol based preparation, use of suture for skin closure, maintenance of glycemic control in the postoperative period, showering (full body) with soap (antimicrobial or non-antimicrobial) or an antiseptic agent on at least the night before the operative day, normothermia should be maintained in all patients, increased fraction of inspired oxygen should be administered during surgery and after extubation in the immediate postoperative period for patients with normal pulmonary function undergoing general anesthesia with endotracheal intubation and transfusion of blood products should not be withheld from surgical patients as a means to prevent SSI [2, 7].
Our finding was also further investigated about the contributing factors of SSI after cesarean section. PROM >12hrs, duration of labor >24hrs, chorioamnionitis, anemia and having vertical skin incision all had increased risk of developing SSI after cesarean section.
Mothers who experienced PROM more than 12hrs had increased risk of SSI than mothers who experienced PROM ≤12hrs duration. This is possibly justified by that feto-placental membrane is one of the barrier essential for prevention or protection of ascending and iatrogenic infection of the membrane (chorioamnionitis). If this protective barrier is breached by any means, it will lose infection prevention. This can lead to ascending and iatrogenic (during per-vaginal examination) infections and will be bacteria reservoir (micro-organisms) and over growth. Unsterile membrane including the fluids which contain infection causing micro-organisms (such as bacteria) will have an access to other organs and tissues during cesarean section that can be potential source of infection after cesarean section. Supporting evidence was also reported from Egypt, India and Australia [39, 45, 46].
The other finding from this systematic review and meta-analysis also indicated mothers who had history of labor duration more than 24hrs had increased risk of developing SSI than mothers whose labor duration was ≤24hrs. Supportive finding was also reported from different country wide studies from India, China, Brazil and Nigeria [39, 41, 47, 48]. Hence, maternal early postpartum complication including infections (SSI) and exposure time where infection can be acquired increased as duration of labor increased. Beyond this, it is also the fact that prolonged labor along with increased number of vaginal examinations also increased the risk of SSI [49]. Labor pain is the severe form of pain causing maternal fatigue and dehydration as well as prolonged vascular diminishing to reproductive tract tissue by the presenting part which make favorable condition for microbes and infection even after the procedure.
Sectional having this evidences, this systematic review and meta-analysis also identified that chorioamnionitis another risk of SSI. Mothers who were diagnosed positive for chorioamnionitis had increased risk of SSI following cesarean section than mothers who don’t diagnosed for chorioamnionitis. Consistent finding was also reported from Canada, Australia and Estonia [38, 46, 50] . Chorioamnionitis is the inflammation of feto-placental membrane that can increase the chance of ascending or iatrogenic infection. This ascending infection can be complicated to sepsis for the both neonate and mother. This infection will affect or migrate to the sterile organs and tissues breached during cesarean section.
Moreover, anemia was also identified as medical factor which exacerbated SSI after cesarean section. Mothers who were diagnosed for anemia had increased risk of developing SSI after cesarean section than mothers who don’t diagnosed for anemia. This finding was consistent with a study conducted in Australia [46]. Anemia is one of the hematologic disorders that negatively affect mothers’ body infection protection mechanism or immune system. Iron is essential element for proper functioning of the host immune system. Low iron level during anemia alters the function of host immune system. In addition, low hemoglobin level causes lower oxygen saturation at peripheral tissue [51]. Delay in wound healing and low infection prevention finally leads to high risk of developing post procedure infection; SSI after cesarean section.
Once more, having history of vertical skin incision increases the risk of SSI. Mothers with history of vertical skin incision after cesarean section had increased risk of developing SSI than mothers with transverse skin incision. Comparable finding was also reported from Nepal[52]. The potential reason may be that, having vertical skin incision is associated with involving more areas, delayed wound healing, higher risk of wound dehiscence, that will put the mothers for risk of developing SSI following the procedure[53, 54].
In our study, a risk bias assessment showed that 7 (63.6%) studies had high quality scores and four (36.4%) had low quality scores. Representation and case-definition biases were the most commonly noted. To determine the influence of low methodological quality/high risk of bias on our estimates of pooled prevalence we estimated pooled prevalence without the low-quality studies. The confidence intervals of our estimates of pooled prevalence with and without these studies overlapped, indicating no significant difference between them. These results suggest that the majority of the primary study authors have met high quality standards. This lends credibility to our findings.
Limitation of the study
This systematic review and meta-analysis included only articles reporting in English language, which may restrict our findings. The majority of the articles use small sample size, might be affect the prevalence estimation. All included studies were cross sectional study design in which the result might potentially affected by confounding variables. In addition the meta-analysis didn’t include all regions and administrative city which only includes four regions and one administrative city of the country. Therefore further country based studies to assess other confounding factors related to health service factors, health policy factors and health care giver related factors for the prevalent SSI in Ethiopia is recommended.