Congenital uterine anomalies: Surgical repair

INTRODUCTION — Congenital uterine anomalies (figure 1A-B) are associated with a variety of gynecologic and obstetric problems. Anatomic correction can be effective in some cases, but in others uterine vascularization and myometrial and cervical function may remain abnormal and prevent the desired functional outcome.

Surgical management of congenital uterine anomalies is reviewed here. The clinical manifestations and diagnosis of congenital uterine anomalies are discussed separately. (See "Congenital uterine anomalies: Clinical manifestations and diagnosis".)

CANDIDATES — Surgery can be an effective intervention in symptomatic patients with specific uterine anomalies:

●Patients with a uterine septum and (1) recurrent pregnancy loss after exclusion of other causes of recurrent pregnancy loss or (2) dysmenorrhea if medical therapy is not effective. (See "Recurrent pregnancy loss: Evaluation" and "Dysmenorrhea in adult females: Treatment".)

●Patients with a bicornuate uterus and recurrent pregnancy loss, after exclusion of other causes of recurrent pregnancy loss. In contrast to the septate uterus, most patients with a bicornuate uterus have pregnancy outcomes close to those of the general population; however, since some patients with this anomaly have recurrent pregnancy loss, uterine reunification is an option after other possible causes of recurrent pregnancy loss have been addressed. (See "Recurrent pregnancy loss: Evaluation".)

●Patients with a noncommunicating uterine horn, functional endometrium on imaging studies, and pelvic pain (figure 2A-B). In addition to symptomatic relief, excision of an obstructed rudimentary blind horn will eliminate reflux, which has been associated with remission of endometriosis, and will eliminate the risk of pregnancy implantation (and pregnancy complications) in the obstructed uterine horn (picture 1A-B) [1].

Surgical correction is not warranted in asymptomatic patients. Surgical correction is also not warranted in patients with primary infertility because these abnormalities typically do not prevent conception and implantation [2]. A review of patients with primary infertility and septate uterus reported the mean pregnancy rate after hysteroscopic metroplasty was only 48 percent, suggesting that the septum was unrelated to their infertility [3]. However, metroplasty may be considered after a complete diagnostic evaluation has been performed and appropriate therapeutic interventions have failed.

Surgical correction of some complex anomalies (cloacal malformation, bladder exstrophy) are best addressed by multidisciplinary teams that may include a gynecologist with expertise in this area, general surgeon, and/or urologist. Some patients with complex anomalies should avoid pregnancy due to the small size of their uterus or risk of pregnancy to the bowel, bladder, or vaginal repair. Adoption, gestational carrier pregnancy, and possibly uterine transplantation should be addressed with these patients if they want to have children. (See "Adoption" and "Gestational carrier pregnancy" and "Uterus transplantation for absolute uterine factor infertility: Ethics, patient selection, and consent".)

SEPTATE UTERUS — Septate uterus is the most common uterine anomaly. (See "Congenital uterine anomalies: Clinical manifestations and diagnosis", section on 'Septate or subseptate uterus'.)

Hysteroscopic metroplasty — Hysteroscopic metroplasty is the preferred method for repair of uterine septa (figure 3A-C). Compared with a transabdominal approach, benefits include lower perioperative morbidity, avoidance of potential pregnancy complications related to transmyometrial incisions, and faster return to normal activity. The transcervical approach reduces the risk of pelvic infection and formation of intra-abdominal adhesions, which may cause future infertility or small bowel obstruction. Patients may attempt pregnancy sooner after a transcervical approach than a transabdominal approach, and future vaginal delivery is not contraindicated. (See 'Postoperative care and follow-up' below.)

Technique — Transcervical resection of a septum is easier when the endometrium is thin because a thickened endometrium limits visualization. Therefore, we typically aim to schedule the procedure in the early follicular phase, which also decreases the risk of undiagnosed pregnancy. Alternatively, a thinner endometrium can be accomplished by pretreatment with a continuous estrogen/progestin contraceptive, progestin-only pill, danazol, or a gonadotropin-releasing hormone (GnRH) agonist. Use of danazol is slightly preferable to use of a GnRH agonist because of lower cost and side effects [4]. Furthermore, use of a GnRH agonist may decrease the size of the uterine cavities and thus limit the ability to perform the procedure.

When the preoperative imaging study clearly establishes the diagnosis and the septum is small, we usually perform the hysteroscopic metroplasty without concurrent laparoscopy. When the imaging study does not clearly establish the diagnosis or the septum is large, we perform a concurrent laparoscopy to evaluate the external uterus (picture 2) and observe the serosa during the procedure to help decrease the risk of perforation. The laparoscopist lets the operator know when the hysteroscopic resection is getting too close to the uterine serosal surface. It helps to dim the laparoscopic light so that the hysteroscopic light can be appreciated.

The goal of the procedure is to reduce the septal surface area. A partial septum may require only incision of the septum, after which it can be seen to "spring away" and open the upper uterine cavity. A large septum requires resection rather than simple incision.

A liquid distention medium (eg, glycine, dextran) is used to distend the uterine cavity. Various techniques and instruments can be used for incision or resection, including semirigid or rigid scissors (7 French) or unipolar wire loop (8 mm) urologic resectoscope (21 to 26 French sheath); Versapoint bipolar electrode (1.6 mm; 5 mm sheath); or potassium titanyl phosphate, neodynamic:yttrium aluminum garnet, or argon lasers. Use of any of these instruments is associated with good success rates and infrequent complications. Use of microscissors or bipolar electrode may decrease operating time [5-7].

Surgical resection using a wire is illustrated in the following pictures (picture 3A-C). With this resection technique, the wire is placed in one endometrial cavity and moved horizontally to the other side, thereby removing the septal tissue. It can be difficult to recognize when the base of the septum has been reached. One approach is to continue cutting until increased bleeding is noted since the septum often has poor blood supply compared with the myometrium, but this approach will not work if a coagulative instrument is used. Alternatively, intraoperative ultrasound or concurrent laparoscopy may be helpful to decrease the risk of uterine perforation.

If two cervixes are present, a Foley balloon catheter is inserted into the uterus transcervically, slightly inflated, and pulled down against the internal os to prevent leakage of the distension media (figure 4). Placing a flexible hysteroscope into the second cervix or instilling blue dye can be helpful for identifying when the hysteroscope has entered the second cavity. The challenge in these cases is placing the first incision so it passes from one side of the septum to the other and does not compromise the internal cervical os of either cervix.

On completion of the procedure, the surgeon should be able to see the interior surface of the fundus and sweep easily between tubal ostia. The uterine cavity should appear normal. In cases with a very thick or highly vascular septum, a staged hysteroscopic procedure may be necessary to limit blood loss, operative time, and fluid/electrolyte imbalance. (See "Hysteroscopy: Managing fluid and gas distending media" and "Overview of hysteroscopy".)

Postoperative care and follow-up — We do not administer postoperative antibiotics or place an intrauterine device or Foley balloon catheter, but some surgeons utilize these adjunctive interventions [8,9]. Endogenous estrogen is sufficient to promote growth of new endometrium within two months of surgery; exogenous estrogen is not needed [10].

A two-dimensional (2D) or three-dimensional (3D) ultrasound or a hysterosalpingogram can be performed two months postoperatively to assess results. Ideally, over 90 percent of the septum should have been removed. If there is a significant residual septum remaining, which happens occasionally, further resection of the septum is necessary [8,11]. In one series, a residual fundal notch greater than 1 cm on follow-up hysteroscopy was considered an indication for repeating the septoplasty; this is a good benchmark since 1 cm is generally considered the definition of a septum [11].

When the procedure is deemed adequate, we tell patients that they can begin attempting to conceive two months postoperatively, as complete healing occurs by this time [10]. Uterine rupture during pregnancy has been reported only rarely after hysteroscopic procedures; therefore, a trial of labor is generally recommended after these procedures in the absence of standard obstetric indications for cesarean birth [12-14].

Complications — Formation of intrauterine synechiae is rare, as is postoperative infection [9]. (See "Intrauterine adhesions: Clinical manifestation and diagnosis" and "Intrauterine adhesions: Treatment and prevention".)

Outcome — Hysteroscopic metroplasty historically has been thought to be associated with improved obstetric outcomes [15-17], but its efficacy is unclear. In a meta-analysis of one randomized trial and 10 cohort studies and including almost 1600 patients with a uterine septum, those undergoing hysteroscopic resection compared with expectant management had lower rates of miscarriage (pooled odds ratio [OR] 0.45, 95% CI 0.22-0.9; 12 studies) and malpresentation (pooled OR 0.32, 95% CI 0.16-0.65; four studies); rates of pregnancy, term live birth, and cesarean birth were similar between groups [18]. While hysteroscopic resection in patients with a partial compared with complete septum was associated with lower rates of preterm birth (OR 0.30, 95% CI 0.11-0.79; two studies), this difference was not detected when comparing patients with septum resection to patients with a septum and no intervention.

However, whether metroplasty truly improves outcome for patients with repetitive pregnancy losses is even less clear. In the multicenter, open-label, randomized trial included in the meta-analysis above and evaluating patients with a septate uterus and a history of subfertility, pregnancy loss, or preterm birth, patients with septum resection compared with expectant management had similar rates of live birth within 12 months of randomization [19]. One hypothesis that may explain this outcome is that in patients with an abnormal uterus in whom surgery is not performed, each consecutive pregnancy may progressively result in a longer gestation so that eventually some patients will deliver a viable infant nearer to term.

Metroplasty may also be associated with a reduction in dysmenorrhea. In a prospective study including 90 patients with a septate uterus and dysmenorrhea, a reduction of dysmenorrhea occurred after either the Tompkins (50 to 32 percent) or hysteroscopic (55 to 18 percent) metroplasty procedure [20]. (See 'Laparoscopic or open transmyometrial repair' below.)

Laparoscopic or open transmyometrial repair — Most uterine septa can be successfully surgically resected hysteroscopically in one or more sessions. In the past, an abdominal metroplasty such as the Jones or Tompkins metroplasty was performed, but these procedures are rarely performed now and presented here for historic completeness. These operations have also been adapted to be performed via laparoscopic and robotic approaches [21,22].

Abdominal transfundal metroplasty procedures are now rarely utilized, given the efficacy and lower morbidity of hysteroscopic metroplasty. Furthermore, the risk of uterine rupture in pregnancy is increased after procedures requiring transfundal hysterotomy, so cesarean delivery is recommended for patients who undergo this procedure. (See "Choosing the route of delivery after cesarean birth".)

●Jones metroplasty – The Jones procedure refers to a wedge resection of the portion of the uterine fundus containing the septum (figure 5A-C). The operator draws a triangular incision line forming a wedge in the anterior-posterior plane of the uterus. Vasopressin can be injected into the myometrium (10 units in 30 mL of saline) to reduce bleeding when the uterus is subsequently incised. Alternatively, a tourniquet, such as a 0.5 Penrose drain, may be placed through an avascular space in the broad ligament just lateral to the uterine vessels and tied at the junction of the lower uterine segment and the cervix. Using the same holes in the broad ligament, tourniquets should also be secured on the infundibulopelvic ligaments bilaterally. It is important that arterial flow is stopped, since uterine congestion and bleeding are increased if only the venous flow is restricted. Sutures should be placed bilaterally for traction, lateral to the area of planned resection. The wedge is then incised until the common uterine cavity is found and the septum can be totally removed.

Reconstruction of the uterus begins at the lower portion of the cavity. The anterior and then posterior walls are closed in either a continuous or interrupted fashion. Some operators inject methylene blue into the uterine cavity prior to the incision, so that the endometrium is easily identified. The first layer should include the endometrium and a small amount of myometrium. The knot should be tied so that it remains in the uterine cavity. The second closure layer is begun inferiorly and performed with interrupted sutures that include the remainder of the myometrium. The final layer, using light suture in a continuous or interrupted fashion, contains the remainder of the myometrium and serosa, attempting to imbricate the rough serosal edges.

●Tompkins metroplasty – The Tompkins metroplasty is similar to the Jones procedure, except that no tissue is removed (figure 6A-C). The uterus is incised in the midline anterior-posterior plane until the uterine cavity is reached (picture 4). The bilateral cavities are then unroofed, using sharp dissection, and the uterus is closed as in the Jones procedure. The benefit of this technique is that the resultant uterine cavity is larger than with wedge resection.

BICORNUATE UTERUS — Variations in the anatomic complexity of the bicornuate uterus have a direct impact on patient outcomes and thus on surgical planning. The initial step is differentiation between a septate and bicornuate uterus (figure 1A-B) using three-dimensional (3D) ultrasonography. The next step is to determine whether the bicornuate uterus is partial (figure 7) or complete (figure 8). (See "Congenital uterine anomalies: Clinical manifestations and diagnosis".)

Patients with a partial bicornuate uterus with an indentation that is less than 1 cm are not an increased risk of adverse pregnancy outcomes and thus do not benefit from surgical intervention. Patients with more severe bicornuate uteri may or may not have an adverse pregnancy outcome, and the adverse pregnancy outcome may or may not be related to the uterine anomaly. For this reason, uterine reunification using the Strassman procedure is only performed in patients with a history of poor pregnancy outcome that is thought to be related to the anomaly after exclusion of other potential causes.

Strassman procedure

Technique — Strassman operation involves a transverse incision across the uterine fundus from one cornua to the other so that both uterine cavities can be visualized. Great care should be taken to avoid the uterotubal junctions. The two uterine cavities are united into one by closing the incision in the opposite (vertical) direction with layers of interrupted suture (figure 9).

Postoperative care and follow-up — We do not prescribe exogenous estrogen for patients with normal ovarian function, but some authors routinely prescribe high-dose estrogen. Placement of an intrauterine device is unnecessary.

We perform a two-dimensional (2D) or 3D ultrasound or a hysterosalpingogram at approximately two months postoperatively to evaluate and document the resulting cavity. Attempts for conception can be initiated three to six months after surgery.

Patients who conceive should be delivered by cesarean as the transfundal incision places them at increased risk of uterine rupture. (See "Uterine rupture: After previous cesarean birth", section on 'Factors that increase the risk of rupture'.)

Complications — Complications include those associated with laparotomy (eg, bleeding, infection), formation of intrauterine adhesions, and uterine rupture in a future pregnancy. (See "Intrauterine adhesions: Clinical manifestation and diagnosis" and "Intrauterine adhesions: Treatment and prevention".)

Outcome — Outcome data are sparse. In the only controlled study of 21 patients (13 managed conservatively and eight managed with abdominal metroplasty), obstetric outcome was not improved [23]. The cumulative pregnancy rates at 24 months in patients without and with surgical correction were 95 and 88 percent, respectively. The probability of giving birth to a live-born infant without corrective surgery in the first, second, and third pregnancy was 30, 58, and 79 percent, respectively. The probability of giving birth to a live-born infant after corrective surgery in the first and second pregnancy was 71 and 86 percent, respectively. These figures are difficult to interpret given the small number of cases and absence of a standardized protocol. They do reflect the increasing likelihood of success with increasing numbers of pregnancies that has been observed anecdotally in patients with uterine anomalies.

OBSTRUCTED RUDIMENTARY HORN — In patients with unicornuate uterus and pelvic pain, including adolescents, ultrasound imaging will help to determine whether a hemiuterus with endometrium is present on the side opposite the unicornuate uterus. If sonographic findings are uncertain, we have found magnetic resonance imaging to be helpful.

If not already done, the kidneys should be imaged to determine whether one or two kidneys are present, whether one or both are duplex (ie, with a double ureter), and the kidney(s) location, as this information can help the surgeon avoid renal or urologic injury during surgery.

Resection of an obstructed rudimentary horn — An obstructed rudimentary noncommunicating uterine horn consistent with the patient's symptoms should be removed laparoscopically [24]. Because obstruction is often associated with retrograde menses, the surgeon should be prepared to deal with endometriosis, which may be at an advanced stage. In most patients endometriosis regresses after relief of the obstructive anomaly, but cases of persistence have been reported [25]. (See "Endometriosis in adults: Pathogenesis, epidemiology, and clinical impact".)

The obstructed hemiuterus may be completely separate from the nonobstructed unicornuate uterus or it can be fused to it. Intraoperative canalization of the single cervix and injection of blue dye will confirm which uterus communicates with the cervix.

For excision of a nonfused obstructed hemiuterus, we begin the hemihysterectomy at the associated round ligament. With traction and electrocautery, the ligament is transected and the retroperitoneal space is opened and the ureter or ureters are identified. The hemiuterus is dissected free from the peritoneum, and the most inferior aspect of the hemiuterus is cauterized and transected. The uterus is then retracted medially and the utero-ovarian ligament is transected. The associated fallopian tube can be excised or left in place if there is concern that removal will compromise the ovarian blood supply and future ovarian reserve [24]. The hemiuterus is then removed from the abdominal cavity.

For excision of an obstructed hemiuterus that is fused with the patent unicornuate system, the procedure may be facilitated with the use of either straight stick or robotic laparoscopy. The fused hemiuterus is excised from the nonobstructed side and then the nonobstructed side is closed in layers.

Postoperative care and follow-up — Postoperative care and follow-up are routine for laparoscopic surgery. Since these patients are not undergoing a procedure to repair their uterine cavity, neither the interventions described above to prevent intrauterine adhesion formation nor follow-up imaging of the remaining unicornuate uterus are warranted. Patients desiring fertility can attempt to conceive immediately after surgery.

Complications — Complications include standard complications of laparoscopy. (See "Complications of laparoscopic surgery".)

Outcome — Most patients experience immediate improvement in pain. If endometriosis was present, it usually resolves once the obstruction has been removed [26], but we have reported cases that persist after correction of the obstruction [25].

SOCIETY GUIDELINE LINKS — Links to society and government-sponsored guidelines from selected countries and regions around the world are provided separately. (See "Society guideline links: Gynecologic surgery".)

SUMMARY AND RECOMMENDATIONS

●Surgical correction of a congenital uterine anomaly is not warranted in asymptomatic patients or those with primary infertility. (See 'Candidates' above.)

●Potential candidates for surgical repair include (see 'Candidates' above):

•Patients with a uterine septum and (1) recurrent pregnancy loss after exclusion of other causes of recurrent pregnancy loss or (2) dysmenorrhea if medical therapy is not effective.

•Patients with a bicornuate uterus and recurrent pregnancy loss, after exclusion of other causes of recurrent pregnancy loss.

•Patients with a noncommunicating uterine horn, functional endometrium on imaging studies, and pelvic pain.

●For patients with septate uterus who are candidates for surgical repair, hysteroscopic metroplasty is the procedure of choice. Ideally, over 90 percent of the septum is removed during the procedure. A two-dimensional (2D) or three-dimensional (3D) ultrasound or a hysterosalpingogram should be performed two months after surgery to assess success; further repairs of the septum are indicated if more than 1 cm of septum remains. Attempts at pregnancy may begin two months postoperatively if the procedure is deemed adequate. (See 'Septate uterus' above.)

●For patients with a bicornuate who are candidates for surgical repair, uterine reunification via laparotomy (Strassman procedure) is the procedure of choice, although evidence of efficacy are sparse. We do not prescribe exogenous estrogen postoperatively for patients with normal ovarian function, but some authors routinely prescribe high-dose estrogen. We perform a hysterosalpingogram at approximately two months postoperatively to evaluate and document the resulting cavity. Patients who conceive should delivery by cesarean as the transfundal incision places them at increased risk of uterine rupture. (See 'Bicornuate uterus' above.)

●For patients with a unicornuate uterus and an obstructed painful rudimentary horn, laparoscopic resection of the obstructed horn is the procedure of choice. These patients commonly have renal and ureteral anomalies and endometriosis, which increase the risk of organ injury during surgery. Intraoperative canalization of the single cervix and injection of blue dye will confirm which uterus communicates with the cervix. Most patients experience immediate improvement in pain. Endometriosis, if present, often resolves postoperatively. (See 'Obstructed rudimentary horn' above.)

ACKNOWLEDGMENT — The UpToDate editorial staff acknowledges Ronald E Iverson, Jr, MD, who contributed to an earlier version of this topic review.