An isthmocele is a defect in the closure of the uterine cavity at the site of the incision following a cesarean section. The protrusion of the isthmocele can cause abnormal bleeding, pain during intercourse, and secondary infertility.
In the isthmocele problem, when the menstrual blood gets trapped in the narrowing and swelling, it can cause severe inflammation in the inner layer of the uterus. This inflammation kills the sperm as they pass from the uterus to the egg and creates an unsuitable environment for the embryo to implant, leading to infertility.
If pregnancy occurs with an untreated isthmocele, there is a higher risk of miscarriage or even rupture of the scar area of the uterus because of the abnormally thin muscle wall where the cesarean section scar sits.
Isthmocele is manifested by brown or cherry brown bleeding.
The exact cause of isthmocele is not fully understood, but is believed to be related to abnormal or incomplete healing of the uterine incision after cesarean delivery. The type of suture used to repair the uterus after cesarean delivery and whether the uterus was repaired with a single or double layer were also effective in isthmocele formation.
Symptoms of isthmocele are abnormal bleeding and secondary infertility. The most common type of bleeding in women with isthmocele is brown bleeding, which continues for several days after normal menstrual bleeding. Spotting can sometimes be seen between menstrual periods, after intercourse or exercise. In some cases, women with an isthmocele have no symptoms at all.
An isthmocele may be suspected if a woman experiences abnormal bleeding or secondary infertility at any time after a cesarean delivery. Women who chart their menstrual cycles may notice isthmocele symptoms sooner than women who do not closely track their menstrual cycles.
Isthmocele occurs in 20 percent of women who have had a cesarean section
Although it is a common problem, affecting about 20 percent of women who have a cesarean delivery, women with isthmocele symptoms can go a long time without a proper diagnosis because many doctors are unfamiliar with the condition.
The most accurate way to diagnose an isthmocele is with an ultrasound procedure called saline infusion sonohysterography (SIS). SIS can determine if there is a defect in the uterine wall at the site of the cesarean section scar, as well as the thickness of the muscle wall remaining at the wound. While it is common for the uterine wall to be slightly thinner near caesarean section, in some cases women with an isthmocele may have a uterine wall thinner than 1 mm.
Isthmocele is treatable
There are several methods of treating an isthmocele, but the most common are hysteroscopic or laparoscopic approaches.
The defective area is trimmed and burned from the inside, preventing menstrual blood from sticking to the scar.
It is the best treatment for women with a uterine wall thickness of more than 5 mm, abnormal bleeding and who do not plan to become pregnant again.
The defect site is completely excised and the muscular wall of the uterus is sutured with 2-3 layers of absorbable sutures. It is the best treatment option for women who have abnormal bleeding, whose uterine wall is less than 5 mm thick, and who want to get pregnant again.
We recommend that any woman with abnormal bleeding or secondary infertility be evaluated for possible isthmocele after cesarean section. Our experience shows that this is a common condition that should be properly diagnosed before discussing treatment options. Effective surgical treatment of this condition can help infertile women and other women regain healthy fertility.