Class U3 and U3bC2 (bicornuate and didelphys uterus), do not appear to reduce fertility but are associated with aberrant outcomes throughout the course of pregnancy, that depend on the type of the congenital anomaly. Generally women with bicornuate uterus have an increased risk of miscarriage (both first and second trimester), preterm birth and fetal malpresentation at birth, while women with uterus didelphys seem to have only a modestly increased risk of preterm labor and malpresentation at delivery [11, 19]. Uterine anomalies have been also associated with an increased incidence of placental abruption, intrauterine growth restriction (IUGR), prematurity, operative delivery, retained placenta and fetal mortality [37]. Obstetrical outcomes are generally reported to be better in cases of bicornuate uterus than in unicornuate uterus, perhaps given the significant variation in bicornuate uterine anatomy, subtypes of which involve a partially fused central uterine cavity [36, 38].

The cause of adverse obstetrical outcomes may be secondary to abnormal uterine vasculature, decreased cervical connective tissue and decreased uterine musculature [38]. Disturbance in the uterine blood flow, caused by absent or abnormal uterine or ovarian vessels, could potentially explain the IUGR and increased rates of spontaneous abortions [8]. Abnormal ratio of muscle fibres to connective tissue in uterine cervices is associated with abnormal müllerian development [7, 40]. Also decreased uterine musculature gestational capacity is said to be jeopardised by the presence of only half the full complement of uterine Musculature. Usually the myometrium of congenitally abnormal uteri are thinner than normal and mural thickness diminishes as gestation advances, causing inconsistencies over different aspects of the uterus [30, 31, 38]

Whether surgical correction for a bicornuate uterus is necessary is controversial although it may be indicated for patients with repeatedly poor fertility outcomes in who other causes have been excluded [26]. Prerequisites are the proper classification, the clear surgical indications and the feasibility and safety features of the procedure.

The Strassman metroplasty is the traditional surgical correction for both bicornuate and didelphic uteri, currently bicorporeal uterus (Fig. 27.2a–e). The Strassman procedure essentially involves the unification of two endometrial cavities of an otherwise divided uterus. A single longitudinal incision from one cornua to the other is made into the endometrial cavity. Retracting the cornua laterally with right angle clamps, each horn of the uterus will evert and a single layer of interrupted figure-of-eight sutures beginning on the anterior uterine wall are placed transversely to form a single uterine cavity. Serosal stitches are placed in a fashion similar to a myomectomy [26, 44]. Resection of a vaginal septum associated with uterine didelphys should be undertaken if associated with obstruction, dyspareunia or infertility. The Strassman procedure has been used to reconstruct the bicornuate uterus [39]. In an uncontrolled study of 289 women with bicornuate uteri and history of previous preterm loss, the fetal loss rate was approximately 70 %. After surgery, the live birth rate significantly improved to 85 % [45]. Further studies concluded that abdominal metroplasty serves as a viable treatment modality to improve obstetric outcomes [27, 34]. In a total of 22 patients after abdominal metroplasty, 88 % of pregnancies ended with the birth of a viable infant [27]. In another study after metroplasty the fetal survival rate was 81 % in the recurrent miscarriage group and 92.8 % in the infertile group of patients [34].

Recently, laparoscopic unification in cases of ESHRE/ESGE U3bC2 (complete bicorporeal with double cervix, formerly AFS didelphys) and U3bC0 (complete bicorporeal with normal cervix) uteri has been reported in the literature [4, 29, 35, 42]. The first laparoscopic metroplasty was reported to be a safe and successful surgical option [42]. It was followed by other case reports and case series showing good restoration of the uterine anatomy, minimal peritoneal adhesions, less blood loss, creation of a spacious uniform uterine cavity, shorter hospital stay and good scar integrity [4, 29, 35].

Strassmann metroplasty is technically quite challenging when performed by endoscopic means and good surgical skills are needed. The same surgical principles as abdominal metroplasty apply. The surgeons must be experienced laparoscopists to perform such procedures [4, 42]. The pregnancy outcomes after endoscopic metroplasty should be evaluated in large prospective trials to prove the obstetric benefit of the procedure.

Metroplasty at the time of diagnosis for patients with primary infertility is not recommended, given that fertility rates are not significantly reduced from the norm and successful pregnancies without intervention are common [11, 19, 38]. Patients should be counseled regarding the need for subsequent cesarean section, given the significant risk of uterine rupture during labour after such procedures [38].

The necessity to perform cervical cerclage is addressed. Cervical incompetence is an issue with uterine malformations, especially with the bicornuate uterus [18]. Because of this potential association, a study was performed using limited prophylactic cervical cerclage in patients with bicornuate uteri (ESHRE/ESGE class U3C0) and comparing fetal survival rate before cerclage to that after cerclage in the same subjects. Fetal survival improved from 21 to 62 % [1]. Further trials are needed to evaluate whether the cerclage is beneficial after metroplasty. It is also not clear at which week of pregnancy it should be performed.

In many cases major congenital uterine anomalies present a management dilemma in women who are symptomatic due to menorrhagia and not responsive to medical therapy. It was reported that the incidence of uterine malformations in women presenting with abnormal uterine bleeding was 19/322 (5.9 %) [28]. In these cases surgical management appears to be the best option and given the established safety of laparoscopic procedure for removal of morphologically normal uteri, it was considered to be a suitable alternative treatment option in a case of didelphys uterus (ESHRE/ESGE class U3bC2). Erian et al. [16] performed a day-case laparoscopic subtotal hysterectomy in a woman with U3bC2 uterus and menorrhagia [16]. Technically, the procedure was similar to laparoscopic subtotal hysterectomy performed in morphologically normal uteri [15]. The most significant difference was the separate removal of the two uterine corpora using two lap loop systems sequentially [16]. It should be noted that surgical identification of the ureters is essential part of the surgery as urinary tract anomalies are frequent in women with uterine congenital malformations [16, 23].

Depending on the anatomical status of cervix and/or vagina, bicorporeal uterus could be presented in some not very common variants (Fig. 27.1); Fedele et al. [17] in an interesting epidemiological study of 87 patients with bicorporeal or septate (“double”) uterus, unilateral cervico-vaginal obstruction and ipsilateral renal anomalies have examined all the anatomic variants and their relative frequency. In 67 out of 87 cases a didelphys uterus was found; in 63 cases with a concomitant longitudinal obstructing vaginal septum (complete bicorporeal uterus with double cervix and longitudinal obstructing vaginal septum – ESHRE/ESGE Class U3bC2V2) and in 4 patients with unilateral cervical aplasia (complete bicorporeal uterus with unilateral cervical aplasia – ESHRE/ESGE Class U3bC3V0). Furthermore, in 10 cases a bicornuate uterus was diagnosed; in 9 patients with double cervix and longitudinal obstructing vaginal septum (partial bicorporeal uterus with double cervix and longitudinal obstructing vaginal septum – ESHRE/ESGE Class U3aC2V2) and in 1 patient with septate cervix and longitudinal obstructing vaginal septum (partial bicorporeal uterus with septate cervix and longitudinal obstructing vaginal septum – ESHRE/ESGE Class U3aC1V2). Didelphys uterus with longitudinal obstructing vaginal septum and ipsilateral renal agenesis is known also as Herlyn-Werner-Wunderlich or OHVIRA syndrome [12, 24, 43, 47]. In all these variants the existing obstruction is the main indication for surgical treatment.