To assess the effects of treatments for prevention of scar tissue (called adhesions) anti-adhesion treatment) inside the womb after surgical treatment in women having difficulty becoming pregnant.
Abdominal adhesions are web-like structures where two normally separate surfaces in the tummy (abdomen) stick together due to damage to the lining of the abdomen. They commonly form after surgery to the abdomen. They can cause multiple conditions such as chronic pelvic pain and infertility. The present practice is based on tradition or observational studies.
We searched for studies that randomly compared any treatment versus no treatment, placebo (pretend treatment) or any other intervention. Outcomes were live birth, clinical pregnancy, miscarriage and presence or severity of scar tissue at the second-look procedure.
We found 16 studies. Treatments included using a device versus no treatment (two studies; 90 women), hormonal treatment versus no treatment or placebo (two studies; 136 women), device combined with hormonal treatment versus no treatment (one study; 20 women), barrier gel versus no treatment (five studies; 464 women), device with the use of membranes of the afterbirth of newborn babies versus device without membranes (three studies; 190 women), one type of device versus another device (one study; 201 women), gel combined with hormonal treatment and antibiotics versus hormonal treatment with antibiotics (one study; 52 women) or device combined with gel versus device (one study; 120 women). From 1273 randomly assigned women, data on 1133 women were available for analysis.
In only two studies, all women had difficulty becoming pregnant. Most studies (14/16) were at high risk of bias for at least one reason. As no study reported live births, we also included data on term delivery or ongoing pregnancy, which five studies reported.
It was unclear whether there was a difference between anti-adhesion treatment compared to no treatment (two studies; 107 women) or to other treatment (three studies; 180 women) for increasing the chance of a liveborn baby, a term delivery or an ongoing pregnancy. The use of some anti-adhesion therapies (device with or without hormonal treatment or hormonal treatment or gels) (eight studies; 560 women) may diminish the risk of scar tissue formation compared to no treatment. We would expect that out of 1000 women treated by surgery, between 153 and 365 women would develop scar tissue after using gels, compared with 545 women when no treatment was used. The evidence was current to 6 June 2017.
Quality of the evidence
The overall quality of the study evidence ranged from very low to low. There were limitations to the studies, for example, a serious risk of bias related to participants and investigators knowing what treatment was given.
More research is needed before anti-adhesion treatment can be offered in everyday clinical practice after surgery of the womb in women having difficulty becoming pregnant.