Do Uterine Fibroids Cause Infertility?
Fibroids are commonly encountered in reproductive aged women. The vast majority of fibroids encountered in the course of an infertility evaluation are not contributing to infertility. The location and size of the fibroid are the important characteristics that determine if the fibroid may be contributing to a couple’s infertility. Large fibroids (generally 5cm in diameter or greater) may cause distortion of the uterine cavity interfering with normal embryo implantation. Fibroids that are totally or mostly within the uterine cavity (submucous fibroids) have been shown to cause infertility or sub-fertility, and in most cases it is advisable to remove these fibroids (myomectomy) to improve prospects for successful pregnancy.
In some situations the majority of the fibroid lies within the uterine wall with only a small percentage of the fibroid projecting into the uterine cavity. In these situations, when infertility is otherwise unexplained, it may be worthwhile to delay surgery while treatment options are attempted. If ovarian stimulation with gonadotropins for 2-3 cycles and IVF fail, it would then be reasonable to remove the fibroid surgically. With these types of fibroids, a skilled surgeon may be able to resect them hysteroscopically (using a small telescope inserted into the uterine cavity trans-vaginally). If attempts to remove the fibroid in this manner fail, an abdominal surgery is necessary to remove the fibroid and repair the uterus properly.
In the case of large fibroids (greater than 5cm in diameter), if there is clearly distortion of the uterine cavity, and the infertility workup fails to identify any additional explanations for the couple’s infertility, removal of the fibroid should be offered. Today, these fibroids may be removed through minimally invasive techniques (laparoscopy) as long as the surgeon is comfortable with this approach. It is important to realize that not every reproductive surgeon has acquired and maintained the necessary skills to perform telescopic removal of fibroids. It is worth seeking out someone with considerable experience doing minimally invasive myomectomy if laparoscopic (telescopic) myomectomy is necessary.
The decision for surgery becomes more difficult if there is one or more fibroid, 3-5cm in diameter present, with no distortion of the uterine cavity and no extension into the uterine cavity. If any other causes for infertility are identified, the couple should receive appropriate treatment for at least three cycles, followed by at least one cycle of in-vitro fertilization before considering surgical removal of these fibroids. If infertility is otherwise unexplained, controlled ovarian stimulation with intrauterine insemination followed by IVF is appropriate treatment before considering myomectomy. There is some evidence that fibroids might be the determining factor for 2-3% of patients with unexplained infertility.
The infertility evaluation should include a careful evaluation of the uterine cavity either by X-Ray (hysterosalpingogram), telescopic evaluation (hysteroscopy), or by sonohysterogram (infusion of sterile saline into the uterine cavity). If hysterosalpingogram or saline sonohysterogram fail to provide unambiguous information, hysteroscopy should be done. Studies have demonstrated that hysteroscopy is the most sensitive test for identifying intra-uterine abnormalities.
It is important to keep in mind that fibroids do not impair fertility for the majority of patients. Occasionally the diagnostic evaluation of an infertile couple clearly identifies a submucous fibroid or a large (greater than 5cm) fibroid significantly distorting the uterine cavity. In these situations, surgery is recommended without delay. For less definitive situations such as the presence of multiple intermediate sized fibroids with no proximity to the uterine cavity, and no uterine distortion, couple focused treatment addressing any significant findings or standard treatment options for unexplained infertility should be offered before any consideration for surgery.