Jamie A. Grifo, Ali Nassari and Alan H. DeCherney
Table Of Contents
Jamie A. Grifo, MD, PhD
Ali Nassari, MD, PhD
Alan H. DeCherney, MD
SYMPTOMS OF MYOMAS|
SIGNS OF MYOMAS
INDICATIONS FOR MYOMECTOMY
COMPLICATIONS OF MYOMECTOMY
MEDICAL MANAGEMENT OF MYOMAS
ROLE OF MYOMECTOMY IN INFERTILITY SURGERY
MYOMECTOMY AND PREGNANCY OUTCOME
|SYMPTOMS OF MYOMAS|
The variation on number, size, and location of myomas results in a spectrum of clinical symptoms and signs. Approximately 20% to 50% of myomas produce symptoms, but many patients are asymptomatic. A review of the literature by Buttram and Reiter2 reveals that 30% of patients with myomas present with menstrual abnormalities, predominantly menorrhagia. Understanding of the pathogenesis of this symptom is lacking, because only 5% of myomas are submucous and could not account directly for the menorrhagia. The abnormal bleeding cannot be attributed to anovulatory cycles, because most women with fibroids ovulate regularly, and there are no controlled studies that document a higher incidence of anovulation in these patients. There are anatomic alterations by myomas in the uterine blood supply (Fig. 1). Interference of myomas with uterine contractility may explain the occurrence of menorrhagia in the absence of submucous myomas.
Infertility is rarely caused by fibroids alone; however, tumor location appears to be more important than size. Infertility patients with myomas need to be evaluated in the same fashion as any infertility patient. According to Buttram and Reiter, only 1% to 3% of patients undergoing myomectomy have no additional cause of infertility.2 However, as many as 30% of patients with causes of infertility in addition to myomas undergo myomectomy. Although no clear etiologic link has been described between myomas and infertility, there are reports of myomectomies in patients with primary infertility and no other detectable causes of infertility, with pregnancy rates as high as 40% after myomectomy. Gehl-bach and associates' life table analysis of patients after abdominal myomectomy demonstrated a cumulative pregnancy rate of 57% and live birth rate of 48%.3 In their analysis, the number of myomas was not associated with pregnancy rate, but the presence of adhesions at the time of myomectomy had a significant impact on reducing the likelihood of conception. Rosenfeld reported a 65% spontaneous pregnancy rate after abdominal myomectomy in patients with unexplained infertility and the diagnosis of subserosal or intramural myomas.4 The size and the number of myomas were not predictive of future fertility.
Enough information exists in the literature to consider fibroids as a cause of infertility, but it is unclear what critical component of fibroids results in diminished fertility. Obstruction of gamete transport and altered endometrial receptivity to embryo implantation are principal mechanisms by which leiomyomas are presumed to prevent conception. In vitro fertilization (IVF) data provide a unique setting for examining this issue. Unfavorable IVF outcomes in patients with leiomyomas strongly suggest reduced implantation rates in these patients.5 Hys-teroscopic resection of myomas in patients with previously failed attempts at assisted reproduction has improved the pregnancy rate without significantly affecting the miscarriage rate.6,7 Leiomyomas that block the fallopian tubes by impingement are rare. There has not been a study to document any endometrial lining defect in patients with myomas, but submucous myomas definitely alter the lining, and inflamed endometrium often covers submucous myomas. Any or all of these findings could explain how myomas cause infertility.
Spontaneous abortion, premature labor, outlet obstruction, and abnormal presentation all occur with increased frequency in patients with myomas. A review of 1941 cases of myomectomy by Buttram and Reiter2 revealed a 41% spontaneous abortion rate before myomectomy and 19% after myomectomy. Spontaneous abortion may result from increased uterine irritability, altered blood supply to the endometrium, and distortion of the endometrial cavity with subsequent interference with implantation.
Pelvic Pressure and Pain
Patients with myomas are at increased risk for developing degeneration with subsequent pain. The differential diagnosis of pelvic pain in these patients includes pelvic inflammatory disease, endometriosis, torsion, aborting myoma, diverticulitis, appendicitis, or ovarian carcinoma. Ultrasound may prove helpful in the diagnosis, as may magnetic resonance imaging. This differential diagnosis is the same as for patients who do not have myomas, except for the entity of degenerating myomas. The distinguishing features of degenerating myomas include severe low abdominal and pelvic pain, uterine tenderness, low-grade fever, leukocytosis, and occasionally peritoneal signs. The location of the myoma may cause the patient to present with pelvic pressure, but this correlates more with uterine size. A fibroid that presses on the bladder may cause urgency, frequency, urinary retention, and even overflow incontinence. A tumor that impinges on the rectosigmoid area can produce constipation or rarely intestinal obstruction. Hydronephrosis and hydroureter can result if it causes pressure on the ureter.
Endometriosis is commonly found in the endometrium superficial to a submucous myoma and may manifest with all of its classic findings: pain, fever, and uterine tenderness. Patients with aborting myomas present with uterine cramps, abdominal pain, fever, and vaginal bleeding, and a mass can be seen protruding through the cervical os. Occasionally, patients with fibroids may present with a rapidly enlarging pelvic mass. Although sarcomatous malignant change in myomas is rare (probably <0.5%), it must never be overlooked in these patients. It is especially ominous in the postmenopausal patient.
|SIGNS OF MYOMAS|
Physical findings in patients with myomas include an enlarged, irregular uterus or pelvic mass. If the uterus is larger than the size at 12 weeks' gestation, it may be difficult to assess the ovaries and be certain that they are separate from the pelvic mass. Patients who complain of menorrhagia have various degrees of iron deficiency anemia. Occasionally, patients present with paradoxical polycythemia, which may be caused by increased erythropoietin levels produced by myomatous tissue. Parasitic myomas may obstruct omental blood vessels and result in ascites. Pedunculated submucous tumors that protrude through the cervical os may manifest with ulceration and infection. Rarely, uterine inversion has been reported with these types of myomas.
|INDICATIONS FOR MYOMECTOMY|
Although there are many clear-cut indications for myomectomy, therapy must be individualized according to the presentation, desires, and relative risks of a particular patient in many situations. Severe menorrhagia in a 26-year-old nulligravid patient with multiple myomas usually is managed by myomectomy, but a 42-year-old patient with the same findings has a set of choices for which only limited data are available for guidance. The choice of hysterectomy versus myomectomy in this situation must take into account that myomectomy has an increased risk of blood loss and replacement, a higher incidence of infectious morbidity, and a much higher incidence of additionally required pelvic surgery (30%). The physician must also consider the patient's strong desire to retain fecundity (albeit much lower in this age group) and the patient's desire to retain the uterus. An increasing number of patients is willing to take a much higher medical risk to have these needs fulfilled. It then becomes the physician's responsibility to educate these patients and help them make informed decisions.
The indications for myomectomy are severe menorrhagia in the setting of leiomyomas, protracted symptoms not responding to medical management, recurrent pregnancy loss in the presence of myomas, obstruction of pelvic organs (i.e. ureters, bowel, bladder, and fallopian tubes) by myomas, rapidly enlarging myomas, infertility resulting from myomas, and myomas of a certain size (still controversial what that size is) when the patient desires to retain fecundity or the uterus. The most controversial aspect about when a myomectomy is indicated relates to uterine size in an otherwise asymptomatic patient. Most investigators believe that if the size of the uterus is less than 12 to 13 weeks' gestational size and is not enlarging, myomectomy is not indicated; however, some believe that the best surgical results for infertility patients occur with uteri ranging in size from 7 to 12 weeks. There are no controlled studies comparing patients with primary infertility resulting only from myomas with uteri in this size range randomized to a surgical or nonsurgical arm. One study suggests that myomectomy may result in decreased infertility. It is suggested that the more conservative approach be adhered to until the proper controlled study is done. The algorithm published by Buttram and Reiter offers a logical approach to the management of myomas (Table 1). Although there are no hard and fast rules, this approach is in agreement with what most investigators have written; however, therapy must be tailored for the individual patient and clinical circumstances.
*Symptoms include bleeding, recurrent abortion, impingement, infertility, and pain; after all other causes were ruled out and patient failed conservative therapy.
Modified from Buttram VC Jr, Reiter RC: Uterine leiomyomata: Etiology, symptomatology, and management. Fertil Steril 36:433, 1981; reproduced with permission of the American Fertility Society.
Techniques of Abdominal Myomectomy
The general principles of sound surgical techniques are as much a part of myomectomy as for any operation. Adequate exposure can be achieved through a Pfannenstiel incision or through a vertical midline incision. However, when the uterus is greater than 16 weeks' size and cannot be delivered through the horizontal incision, a vertical midline incision may be more appropriate. The surgeon must also take into account the location of the myomas before deciding on the incision. For instance, a broad ligament myoma may require dissection in the pelvic sidewall with subsequent unroofing of the ureter; this is done more easily through a vertical midline incision. Good clinical judgment rather than controlled clinical studies provides better guidance in these situations. A mild Trendelenburg position helps ensure exposure. Gloves must be washed to remove free talc particles and laparotomy pads placed in plastic bags to limit the exposure of the peritoneal surfaces to adhesion-promoting substances. Gentle handling of the tissue is thought to reduce the likelihood of adhesions. Although there is little that may be gentle about myomectomy, the surgeon can operate in such a manner as to minimize tissue damage.
After the field is clear and exposure is adequate, the surgeon must plan the uterine incision. This decision is based on the number and location of the myomas. The most preferred incision is a vertical incision on the anterior surface of the uterus. This minimizes blood loss and keeps the ovaries from adhering to the posterior wall of the uterus postoperatively. Occasionally, the surgeon must perform “transcavity enucleation” as described by Bonney,8 to avoid a posterior incision. In this manner, posterior fibroids can be removed through an anterior uterine incision, which avoids the hazards of a posterior incision. The caveat with this method is that the surgeon must affirm that the posterior defect is adequately repaired, that the cavity must not be compromised by suture, and that subsequently delivery be performed by cesarean section. The surgeon often can remove multiple myomas from a single incision, whereas at other times, multiple incisions are required. Although there is no proof, it is felt that minimizing the amount of damaged peritoneal surface relates linearly to the extent of adhesion formation. Minimizing the length of the uterine incision and the number of uterine incisions is a general strategy to be employed.
Another method for approaching the posterior myoma has been described by Bonney and is called the Bonney hood (Fig. 2). This approach uses a transverse posterior fundal incision and subsequent enucleation of the myoma. After interrupted sutures in layers are used to close the dead space, the extra serosa is sutured with fine suture to the anterior surface of the uterus, creating a functional anterior incision. This allows a posterior approach but avoids a posterior defect.
The general strategy employed for removing a myoma regardless of location involves incising through the pseudocapsule of the myoma. This maneuver exposes the tissue planes and allows isolation of the capsule with Allis clamps. Blunt and sharp dissection is used to peel the myoma out of the capsule. The surgeon can use a knife, Mayo scissors, electrocoagulation, laser, or blunt dissection to accomplish this. At some point, the blood supply to the myoma is encountered and is best handled by clamping or ligating before incising. This results in the excision of the myoma, leaving an oozing cavitary defect in the uterus. If more myomas are resectable through this incision, they are removed at this point; otherwise, the wound is closed. With this method, the surgeon mindful of vital adjacent structures (e.g. ureters, uterine vessels, cornua) to avoid pelvic injuries.
Closing the resultant uterine defect involves much individualization of approach. The goal is to restore normal anatomy and to ensure adequate hemostasis, which requires attention to filling in the dead space. Despite meticulous attempts to achieve this, much area often remains open and fills in with blood. The resultant tamponade eventually aids in hemostasis, but these pockets of blood provide a rich culture medium for infection. Although some advocate the use of continuous suture in this area, interrupted sutures afford greater chance at tissue approximation, minimizing dead space. Layered interrupted sutures are time consuming but provide the best opportunity at tissue coaptation. After the myometrial layers have been adequately reapproximated, excess serosa may be trimmed and the serosal defect repaired with a fine polyglycolic suture in a running “baseball” fashion. This allows a minimum of exposed suture material and decreases adhesion formation (Fig. 3).
Techniques to Reduce Blood Loss
Myomectomy is perhaps one of the bloodiest gynecologic operations performed, and the most significant morbidity associated with it includes blood loss. A variety of methods have been described that are aimed at minimizing blood loss. The two main approaches, medical and mechanical, diminish uterine blood flow to the myoma. The blood supply to a myoma is highly variable, and it is difficult to predict the blood vessel location when dissecting the myoma. The anatomy can be significantly distorted by the myomas, such that even the major blood supply to the uterus may be altered. The optimal uterine incision to minimize blood loss is an anterior, vertical incision. This cuts across a minimum of collateral channels and a minimum number of blood vessels.
One popular medical approach to decreasing blood loss in myomectomy uses 8-L-arginine vasopressin (Pitressin). Dilute solutions of this are injected directly into the myoma, raising a circumferential wheal and causing vasoconstriction. Other agents such as Pitocin and epinephrine have also been used. Most investigators report using pitressin diluted from 0.2 to 1 unit per milliliter of diluent, using a maximum of 20 units total. Some feel that this is unnecessary and that it only delays bleeding. It does blanch the tissue and provide better visualization of the tissue planes. Although the drug is not approved by the U.S. Food and Drug Administration for this use, many have used it safely for a number of years. Physicians must be cognizant of the potential side effects of this medication, as for any medication. Its use is contraindicated in patients with epilepsy, migraine, asthma, heart failure, and nephritis. In patients with documented coronary disease, angina, and even myocardial infarction has been described. Myomectomy is rarely performed in such patients. Pitressin may produce water intoxication, the early signs of which must be recognized. Headache, drowsiness, and listlessness always precedes convulsions and coma, which can result from severe overdosage of this medication.
The most direct method to minimize blood loss during myomectomy is to use mechanical methods that decrease uterine blood flow. Many methods have been described using a variety of clamps and tourniquets, but all apply the same general principle. Bonney8 first described the use of an atraumatic clamp that compresses the uterine vessels and decreases uterine blood flow. The Bonney clamp is applied from the pubic end of the abdominal wound; it must contain the round ligament in its grip, or it slips below the uterine vessels. Blood flow from the infundibulopelvic ligament is compressed using a ring forceps; the uterine blood flow is essentially stopped. The location of the ureter must be known before applying any clamps. Other variations of this method use bulldog clamps, rubber-shod clamps, or tourniquets. The disadvantage of using a tourniquet is that a small incision is often made in an avascular area or the broad ligament (although this does not have to be done).
The tourniquet is then applied around the cardinal ligaments, obstructing uterine vessel blood flow. A tourniquet can also be applied around the infundibulopelvic ligament in a similar fashion. The defect in the broad ligament must be repaired with a fine suture and therefore becomes another site for possible adhesion formation. The unknown aspect of these mechanical methods is the duration that the blood supply to the uterus can be occluded before irreversible ischemic damage occurs. Some investigators recommend that the clamps or tourniquets be released every 15 minutes to prevent this phenomenon. Ranney and Frederick1 described a histamine-like substance that accumulates in the uterus that has its blood supply obstructed. They suggest that this may lead to postoperative shock. There are no reported cases of postoperative thrombosis of the uterine vessels, necrosis of the uterus, and damage to the tubes and ovaries, but the physicians must be aware of the potential hypoxic injury to the uterus with this method.
An additional strategy for minimizing the risk during myomectomy involves the use of autologous blood. The acquired immunodeficiency syndrome (AIDS) crisis has resulted in many hospitals offering patients undergoing elective surgery the option of donating their own blood preoperatively. This alleviates the AIDS risk and protects against hepatitis, which is a much more common problem. Although this is not always practical for the patient with menorrhagia, it does allow many the option. In the patient with large fibroids, gonadotropin-releasing hormone (GnRH) agonists can be used concomitantly to shrink the myomas. The GnRH agonists allow time for the patient to bank autologous blood, and they decrease the size of the myomas and thereby make myomectomy technically easier. Patients can store up to 1 unit every 2 weeks, and with the ability to freeze autologous blood, a large quantity of blood can be obtained. These patients should be given supplemental iron during this time. The cell saver has also been used, but there are not many reports regarding its safety in this type of procedure.
Techniques to Prevent Adhesion Formation
Perhaps the biggest threat that myomectomy poses to fertility is that of adhesion formation. Gehlbach and colleagues demonstrated that adhesions, even at the time of myomectomy, significantly reduces the likelihood for future conception.3 Second-look laparoscopy has demonstrated the formation of a significant degree of pelvic adhesions as early as 8 days after abdominal myomectomy.9 Higher degrees of adhesion have been demonstrated with posterior wall incisions, uterine size larger than 13 weeks' gestation, and with myomectomies involving intramural myomas. Multiple strategies have been described for minimizing this potential complication. The vertical, anterior uterine incision can minimize blood loss and prevent the formation of adhesions that involve the tubes, ovaries, or bowel. This incision should be employed if feasible. Other strategies engage a variety of uterine suspension techniques; medical approaches using dextran 70, promethazine, and corticosteroids; copious irrigation; and meticulous hemostasis. The uterus can be suspended in the classic manner described by Gilliam, and the round ligaments are sutured to the fascia with silk sutures. Mattingly and Thompson10 describe a modified Gilliam suspension using delayed absorbable suture. Olshausen11 describes a procedure that fixes the uterus to the anterior abdominal wall and in some respects is similar to a Gilliam suspension. However, Mattingly and Thompson suggest that the anchored uterus is a source of pain during pregnancy.10
Another strategy for reducing postoperative adhesion formation was described by Horne and associates.12 They demonstrated that treatment with intravenous Decadron (20 mg) and intramuscular Phenergan (25 mg) every 4 hours for 48 hours postoperatively can significantly reduce adhesions. DiZerega and Hodgen13 showed that instillation of 100 to 200 ml of 10% dextran 70 into the pelvic cavity at time of closure also reduces adhesion formation by a flotation effect. Diamond and others14 are actively pursuing the potential for Interceed (TC-7) and HAL-F (Seprafilm) to prevent adhesion formation.
Other means aimed at reducing adhesions involve gentle handling of tissue, placing laparotomy pads in plastic bags to prevent lint particles from escaping, removing particles from gloves, meticulous hemostasis, and copious irrigation with heparinized Ringer's lactate (1000 units/1000 ml). Although none of these methods has been proved to prevent adhesions, most investigators make mention of them.
Rarely, a myoma manifests as a mass protruding through the cervical os. Invariably, these tumors are pedunculated submucous myomas, which may make them amenable to removal through the vaginal approach. This form of myomectomy has the risk of increased infection, and occasionally hemostasis cannot be achieved, forcing the surgeon to proceed to abdominal hysterectomy. Despite these hazards, this approach has the advantages of not entering the peritoneal cavity with subsequent adhesion formation, producing a much faster recovery, causing generally lower blood loss, and being a less deforming procedure. Goldrath15 described the use of laminaria tents preoperatively to dilate the cervix and aid exposure of the pedicle. The surgeon can double clamp the pedicle and incise the stalk with cautery or a knife and then place Heaney-type sutures of 0-Vicryl. When this is feasible, a relatively fast operation can be done. A myomas with a thicker stalk does not always permit this approach, and the surgeon can incise the pedicle with cautery. The pedicle usually then recedes into the uterine cavity, and the physician observes for bleeding. If hemostasis cannot be achieved by conservative management, hysteroscopy can be performed to attempt hemostasis using directed cautery. If this fails, the surgeon can attempt to pack the uterus and vagina and carefully observe the patient. The last resort is to perform an abdominal hysterectomy.
The physician should always use prophylactic broad-spectrum antibiotics for this operation, because the risk of infection is especially high. These patients should be counseled preoperatively about these risks and the possibility of abdominal hysterectomy. Despite the hazards, this operation usually results in a good outcome. Goldrath reports that 83 of 92 patients had successful vaginal myomectomies.15
Hysteroscopic Resection of Myomas
The patient with symptomatic submucous myomas presents the clinician with a therapeutic challenge. When the uterus is small, an abdominal myomectomy has distinct disadvantages. Dilation and curettage (D&C) does not often resolve the menorrhagia, and multiple D&Cs frequently must be performed. Hormonal therapy is often ineffective. The patient who presents with menorrhagia needs a diagnosis, and the most direct approach is to perform hysteroscopy in addition to endometrial sampling. This approach distinguishes between submucous myomas, dysfunctional uterine bleeding, endometrial polyps, and neoplastic causes.
The patient who has submucous myomas as the cause of menorrhagia has many options for treatment. For the patient who does not desire fertility, vaginal or abdominal hysterectomy is appropriate management. The patient who desires fertility has two options: hysteroscopic resection and abdominal myomectomy. Not having to enter peritoneal cavity reduces the likelihood of adhesion formation and clearly favors hysteroscopic resection. Hysteroscopic resection is rapidly becoming the method of choice for the surgical treatment of submucous myomas. Data suggest that hysteroscopic resection provides fertility results that are comparable or perhaps superior to abdominal myomectomy while providing the added benefit of lower incidence of postoperative morbidity and shorter length of hospital stay.16 Neuwirth17 described 28 patients who underwent hysteroscopic resection of submucous myomas and had long-term follow-up. The patients were between 25 and 48 years of age at the time of surgery; therefore, it is difficult to make firm conclusions about postoperative fecundity. However, 17 of the 28 patients had normal menses postoperatively, 7 underwent hysterectomy, 2 were lost to follow-up, and 2 had repeat resections. Of the 17 patients, 5 became pregnant with a total of 8 pregnancies. These numbers suggest that this method is a viable treatment option for the infertile patient with symptomatic submucous myomas. However, hysteroscopy is not without its risks. Although rare, uterine perforation, distention, medium hazards, infection, and hemorrhage are serious complications. The patient must be counseled about the possibility of altered menses postoperatively and the unknown potential for Asherman's syndrome.
The technique of hysteroscopic resection sometimes requires laparoscopic guidance. This prevents the possibility of damage to intraabdominal structures during the procedure. The instruments required are a urologic resectoscope that is designed to pass through the hysteroscope. The uterus is distended with 32% dextran 70 delivered by pump or by hand-held syringe. A cutting electrosurgical current (30 watts) is delivered by a cautery unit. The submucous myoma is shaved down to the surface of the surrounding myometrium, and hemostasis is ensured (Fig. 4). A sterile 12- or 14-French Foley catheter may be placed in the uterine cavity and distended to provide tamponade and further ensure hemostasis when necessary. This is left in place overnight. Premarin (2.5 to 5 mg) is given daily for 21 days to avoid Asherman's syndrome. The patient's recovery is relatively quick. This procedure requires an experienced surgeon with highly specialized training. Some investigators have used preoperative GnRH analog to shrink the myoma, although there are no controlled studies to document the benefit.
Many investigators have written about the use of laser in performing myomectomy. The laser results in less adhesion formation, perhaps because of less tissue damage. Some authorities believe that better hemostasis can be achieved with the laser. Statements about improved reproductive performance have also been made. Reyniak and Corenthal18 described a method of using a hand-held laser and microsurgical techniques with a 70% pregnancy rate postoperatively in a small series. McLaughlin19 used a carbon dioxide (CO2) laser for metroplasty and myomectomy and claimed that there was less blood loss and less tissue damage. Starks20 reported a 59% viable term pregnancy rate for 24 patients undergoing CO2 laser myomectomy. He states that the advantages of the CO2 laser for myoma surgery are decreased adhesion formation and improved reproductive performance. Although these initial results are promising, it is technically difficult to design a controlled study to document these claims with greater certainty. It is safe to say that the laser is at least equal to conventional myomectomy, but the data showing superiority are lacking.
The laparoscopic approach to myomectomy is becoming increasingly popular. It has been argued that, compared with the abdominal approach, this technique offers a lower degree of blood loss, a shorter length of hospital stay, and a lower overall complication rate.21 However, the procedure is not without its drawbacks. Laparoscopic resection of multiple myomas is more time consuming, larger myomas are more difficult to remove from the abdomen, and adequate repair of the myometrium after removal of an intramural fibroid is often too difficult to accomplish.
Semm wrote about pelviscopic myomectomy using specialized pelviscopic instruments. After numerous procedures, subsequent laparoscopy in a number of patients revealed a minimum of adhesion formation. The surgeons devised a number of methods to ensure hemostasis and to morcellate the tissue to allow its removal laparoscopically. The procedure is limited mainly to the removal of subserosal myomas, although it has been used to remove intramural myomas. Blood loss is reportedly minimal, and hemostasis is achieved with a minimum of complications. This operation is limited to small myomas and should be performed only by the surgeon skilled in operative pelviscopy.
Based on their experience with 109 myomectomies, 70 of which were performed laparascopically, Darai and colleagues recommended that laparoscopic myomectomy be reserved for patients presenting with the maximum number of four myomas, with none surpassing a diameter of 7 cm.22 Comparable spontaneous pregnancy rates have been reported after laparoscopic and abdominal myomectomies in selected groups of patients.23 However, these results should be considered in the context of the criteria chosen for patient selection. The outcome of the method employed is closely associated with the size of the myoma, the number of myomas present, and myoma location. Inadequate uterine repair after laparoscopic myomectomy may result in grave obstetric consequences because of uterine rupture.24,25 Women of childbearing age with symptomatic intramural fibroids should undergo abdominal myomectomy or a modified laparoscopic procedure to ensure proper closure of the myometrial defect.26It may be more prudent to reserve the complete laparoscopic approach for the pedunculated and subserosal fibroids.
|COMPLICATIONS OF MYOMECTOMY|
Myomectomy is a technically difficult operation and is fraught with hazards. The major potential complication is hemorrhage; however, the risks of infection and required future pelvic surgery also are in excess of that of hysterectomy. Additional potential complications include those of any pelvic surgery: bowel obstruction; adhesion formation; damage to bowel, bladder, fallopian tube, and ureter; general anesthesia; wound infection; and wound separation. Roughly 20% to 25% of patients undergoing myomectomy require another pelvic operation, usually hysterectomy. Recurrent myomas are common, especially in patients with multiple myomas. Patients with a solitary myoma have a 27% recurrence rate, and those with multiple myomas have a rate of 59%. When the uterine cavity is entered, a cesarean section is required in a subsequent pregnancy. A patient undergoing myomectomy should be counseled preoperatively about these risks and must understand that a myomectomy may not be possible. Although it is not common, uncontrolled intraoperative hemorrhage may require a hysterectomy. Because it is difficult to predict preoperatively which patients will require this procedure, all patients should be warned of the risk. The patient must also be aware of the increased potential for blood transfusion intraoperatively and during recovery. Significant febrile morbidity results, and it is often difficult to distinguish infection from fever caused by the release prostaglandins during myomectomy. Nonsteroidal antiinflammatory agents are often useful in preventing this type of fever.
A significant but not easily quantified complication of myomectomy is that of infertility caused by the procedure. Some information in the literature suggests that myomectomy may cause infertility. Adhesions that limit the mobility of the adnexa may decrease the ability of the fimbria to pick up an oocyte. They may also isolate the fimbria from the ovary. It is not clear whether peritoneal adhesions limit fertility, but they may contribute to the problem.
|MEDICAL MANAGEMENT OF MYOMAS|
The role of GnRH analogs as adjunctive therapy for myomas is controversial. There are many reports about the ability of these agents to shrink myomas; however, cessation of therapy is accompanied by rapid regrowth of myomas. A study by Andreyko and colleagues27 demonstrated by magnetic resonance imaging that nafarelin was able to decrease myoma size by 46% and uterine volume by 57%. Kessel and associates28 evaluated the use of agonist analogs of GnRH for treating fibroids and confirmed the decrease in uterine size and cessation of menometrorrhagia. They found that GnRH analogs were effective in three of five patients with uterine fibroid associated infertility. Intrauterine pregnancies resulted in these patients with no other therapy. Although these agents can cause a significant reduction in size of myomas, it is not clear that this offers any distinct advantage as a preoperative therapy. There are reports of decreased blood loss from this management, but this is difficult to prove. Many debate that this treatment causes the capsule to become fibrotic and hence makes surgery more difficult. Others doubt that there is any benefit from preoperative GnRH analog therapy.
One effective use of GnRH therapy is in patients with myomas and menometrorrhagia. These patients can be temporized with the analog while being prepared for surgery. Autologous blood can be stored, endometrial sampling can be performed, and surgery can be done electively. Maximum benefit in regard to shrinking myomas is seen after approximately 6 to 8 weeks of therapy. It is recommended that therapy be started during the luteal phase (day 21) to minimize the estrogen withdrawal bleeding that occurs about 10 days after commencement of therapy. Patients tend to remain amenorrheic and hypoestrogenic if properly suppressed. The physician can monitor this status with serum estradiol, follicle-stimulating hormone, and luteinizing hormone levels.
|ROLE OF MYOMECTOMY IN INFERTILITY SURGERY|
There are numerous reports that patients with unexplained infertility and myomas have increased fecundity after myomectomy. Babaknia and colleagues29 evaluated 34 patients with primary infertility and 12 patients with secondary infertility. After myomectomy, 38% of patients with primary infertility and 50% of those with secondary infertility had term pregnancies. An interesting finding in this study was that distortion of the uterine cavity did not correlate with postoperative fecundity. Many other investigators have reported an approximately 50% pregnancy rate after myomectomy, with 75% of these occurring in the first year. These findings have been confirmed by Rosenfeld,4 who evaluated 23 patients with unexplained infertility and myomas. In this study, 65% of patients conceived after myomectomy, all but one within the first year. The age of the patient, duration of infertility, size and number of fibroids, hysterosalpingography, or presence of menorrhagia did not predict pregnancy outcome.
One study suggests that myomectomy may decrease fertility, probably because of adhesion formation. In this study, 50% of the patients conceived; however, the most important correlation with subsequent fertility was surgical indication. Only 16% of patients with a normal infertility evaluation conceived, whereas 68% of patients who underwent exploration for a pelvic mass conceived. These investigators conclude that myomectomy may decrease fertility in the patient with unexplained infertility and that it may be unjustified.30 However, one review of 23 trials between 1982 and 1996 demonstrated a conception rate of more than 60% for infertile patients after myomectomy.31
Although there may be little doubt about the effectiveness of myomectomy in improving spontaneous conception rate of patients with unexplained infertility, the effect of myomas and the significance of their location in the uterus on the success of assisted reproductive technologies has been a matter of debate. Although the effect of subserosal and corporal myomas away from the uterine cavity may be minimal, submucosal and intramural myomas significantly reduce pregnancy and implantation rates, even in the absence of uterine cavity deformity.32,33 At a minimum, medical or surgical treatment is recommended for patients with intramural or submucosal myomas before employing one of the techniques of assisted reproduction.
|MYOMECTOMY AND PREGNANCY OUTCOME|
Pregnancy outcome results after myomectomy have varied. In one series, 28 (82.4%) of 34 married patients gave birth to a total of 48 babies after myomectomy. Buttram and Reiter2 reviewed 18 studies containing 1193 women who had myomectomy for infertility, 40% of whom conceived postoperatively. They also compared spontaneous abortion rates preoperatively and postoperatively and found them to drop from 41% to 19% after myomectomy. It appears that myomectomy improves pregnancy outcome significantly. The one caveat about myomectomy is that it often requires subsequent delivery by cesarean section. Although uterine rupture is rare in postmyomectomy patients when the uterine cavity is entered, operative delivery is considered mandatory.
Myomectomy will become a more popular operation as the trend to delay childbearing continues. The popular view that unnecessary hysterectomy is performed all too often has patients requesting this more morbid procedure. The role of this procedure in infertility will increase despite or perhaps even because of the development of the new reproductive technologies. A century of experience with myomectomy has improved the technique dramatically. New technology and innovative minds will continue this trend.34,35
10. Mattingly RF, Thompson JD: Leiomyomata uteri and abdominal hysteroscopy for benign disease. In Mattingly RF, Thompson JD (eds): TeLinde's Operative Gynecology, p 203. 6th ed. Philadelphia: JB Lippincott, 1985
27. Andreyko JL, Blumfeld Z, Marshall LA et al: The use of an agonistic analog of gonadotropin releasing hormone to treat leiomyomas: assessment by magnetic resonance imaging. Am J Obstet Gynecol 158: 903, 1988
32. Eldar-Geva T, Meagher S, Healy DL et al: Effect of intramural, subserosal, and submucosal uterine fibroids on the outcome of assisted reproductive technology treatment. Fertil Steril 70: 687, 1998