SANTA BARBARA, CALIF. – Surgical hysteroscopy may be the most efficient way to restore fertility in women with cesarean-induced isthmoceles, but no randomized trials exist to guide clinicians concerning what may loom as a notable contributor to secondary infertility.
Reservoirlike pouch defects develop on the anterior wall of the uterine isthmus at the site of a cesarean section scar in an unknown percentage of women, explained Dr. Mousa Shamonki at an annual conference on in vitro fertilization and embryo transfer sponsored by the University of California, Los Angeles.
"This may be a cause of fluid accumulation in the uterine cavity, or be associated with abnormal uterine bleeding," said Dr. Shamonki, director of in vitro fertilization and assisted reproduction at the university.
Surgical correction, he added, "may correct bleeding and fluid accumulation, and potentially restore fertility."
"You’ll notice I’m being very careful in my verbiage here," he emphasized, noting that the lack of epidemiologic data or randomized trials makes the scope of the problem and its treatment unclear.
With cesarean deliveries’ constituting nearly a third of live births in the United States, any common complication is likely to powerfully impact gynecologic and obstetrical practice.
In a recent review, Dr. Pasquale Florio and his associates at the University of Siena (Italy) suggested that cesarean section–induced isthmoceles may interfere with passage of menstrual blood through the cervix, and the accumulated fluid may lead to suprapubic pelvic pain and postmenstrual abnormal uterine bleeding (Curr. Opin. Obstet. Gynecol. 2012;24:180-6).
"Moreover," the authors wrote, "persistence of the menstrual blood after menstruation in the cervix may negatively influence the mucus quality and sperm quality, obstruct sperm transport through the cervical canal, [and] interfere with embryo implantation, leading to secondary infertility."
The diagnosis of cesarean-induced isthmocele can be reliably made by transvaginal ultrasound, they stated.
In the largest treatment series to date, the same group reported in 2011 on 41 consecutive patients in whom other causes of infertility had been ruled out, and whose cesarean-induced isthmoceles were hysteroscopically excised (J. Minim. Invasive Gynecol. 2011;18:234-7).
"Believe it or not, all patients spontaneously conceived 12-24 months after isthmoplasty," said Dr. Shamonki.
Also, isthmoplasty resolved the postmenstrual abnormal uterine bleeding and suprapubic pelvic pain in all patients.
"It appears promising," he acknowledged. "But again, this is not a randomized trial. It’s very important that we get more information."
The talk generated considerable interest at the meeting, which draws reproductive medicine specialists from around the world.
In an interview, Dr. Ivan Valencia from Quito, Ecuador, estimated that in his reproductive endocrinology practice, 60%-70% of infertile patients with a history of cesarean section have evidence of an isthmocele. Deep suturing or an exaggerated healing response is likely to blame, he noted.
In such patients, he creates a small hole through the stenotic tissue on hysteroscopy that is performed without anesthesia during patients’ initial office visit. "Many patients get pregnant the next month and you don’t have to do IVF."
In others, the procedure eases the embryo transfer procedure, said Dr. Valencia.
Dr. Valencia hypothesized that isthmocele is very common following cesarean deliveries. "In some cases, this scar is not affecting them," he surmised. "They don’t come to see a specialist."
Dr. Shamonki reported that he had no relevant financial disclosures.