Hysteroscopic Lysis of Intrauterine Adhesions
If one or more myomas were removed because of symptoms, or to improve the likelihood of a successful pregnancy, then attempts to achieve a successful implantation may be stymied by the resultant scarring.
The key to increasing the cure rates for postmyomectomy Asherman's syndrome—and to reducing the incidence and severity of postmyomectomy scarring—could lie in the approach to fibroid removal.
The best approach for a woman who may want to become pregnant in the future, and who has a myoma that occupies a fair amount of the endometrial surface, may be to extract it abdominally. This approach provides a better chance of sparing the endometrium because the fibroid can often be “peeled” away from the endometrial surface, thereby maintaining the basalis layer within the outer layer of the myoma's capsule.
If the hysteroscopic approach is used, all of the endometrium over the surface of the myoma will be removed in order to extract the tumor.
The European Society of Hysteroscopy's classification of myomas is a helpful guide to plan the ideal route of surgery based on the extent of the intracavitary component. I have found this system—coupled with the size and location of the tumor (or tumors) and the patient's desire for future fertility—to be very useful in planning the ideal surgical approach.
We also should be extremely selective in our use of GnRH agonists. These agents allow anemia to be reversed, cause endometrial atrophy, and can make myomectomy easier to perform. However, the atrophic, estrogen-depleted endometrium may be more prone to adhesion formation.
To prevent intrauterine scarring following a D&C performed for postpartum hemorrhage 2–4 weeks after delivery, when the uterus is most vulnerable to scarring, I would propose to the patient that she not breast-feed, that a splint be placed in her uterus, and that she receive estrogen therapy. Although there are no studies on the efficacy of this prophylactic approach, these measures may help prevent the development of intrauterine adhesions, which are quite difficult to cure.
Administering prophylactic antibiotics at the time of D&C is a common practice and may help prevent subclinical infection. For the pregnancy loss that occurs very early in gestation, medical rather than surgical termination may be considered as a method of reducing the risk of scar formation. If curettage is necessary, it is advisable to perform surgery shortly after the fetal demise has been diagnosed. Curettage performed long after fetal demise is associated with a higher risk of scar formation, probably because some degree of fibrosis has begun.
Subsequent Pregnancy
The overall pregnancy rate after successful treatment for intrauterine adhesions is approximately 75%. (Other causes of infertility prevent us from reaching 100%.) In patients who conceive, approximately 85% of the pregnancies are successful. During pregnancy, there are several potential complications that must be anticipated in patients who have been treated for Asherman's syndrome. One is an incompetent cervix. These patients often have had many cervical dilatations because of curettages and hysteroscopies before becoming pregnant. An ultrasound can be used to assess the shortening of the cervix and any funneling of the membranes.
We must also consider the possibility of placenta accreta, which can be easily diagnosed with either high-resolution ultrasound or MRI in late pregnancy.
The advantages of suspecting the problem are several. For example, a patient can bank her own blood because placenta accreta can be associated with significant blood loss at delivery, and she can plan the timing and/or site of her delivery to optimize hospital resources and ensure access to a large amount of blood products and consultants from various specialties.
Even if the placenta appears to have been delivered complete and intact, uterine exploration is advised to verify that there are no retained fragments. Placenta accreta occurs significantly more often in patients who become pregnant with only partially treated Asherman's syndrome than in patients whose uterine cavity is normal. The successful-pregnancy rate in patients with incompletely resolved intrauterine adhesions is only 20%, and 18%–28% of these patients will have placental complications.
This means that once a diagnosis of intrauterine adhesions has been made, the patient should be offered therapy if she wishes to conceive. The recommendation to “try to conceive and see how it works” is a recipe for a bad outcome.
About 20% of my patients have needed more than one procedure in order to restore the cavity to normalcy. The second—or, rarely, even a fifth—procedure may be considered extreme if the postoperative HSG and ultrasound that followed a prior hysteroscopic adhesiolysis were “pretty normal.” However, the poor outcome in those with partially treated disease speaks volumes, especially in women who are older and are less fertile than in the past.
