Recurrent large uterine fundal dehiscence during cesarean section after hysteroscopic uterine septum resection with uterine perforation

Introduction

Uterine septum, which is an incomplete septated uterus or uterus subseptus, is the most common form of congenital uterine anomaly. Depending on the size of the septum, it is related to adverse reproductive problems such as pregnancy loss, infertility and obstetric complication [1].

Hysteroscopic septum resection has been accepted as a safe, rapid and effective procedure [2]. Although septum resection using hysterescopy is safe, some late complications may be seen such as uterine rupture or dehiscence of uterine wall during pregnancy due to myometrial damage [3].

Defects in the integrity of the myometrium may leave the uterus susceptible to rupture in a subsequent pregnancy, particularly if the hysteroscopic surgery violated the integrity of the myometrium. A review involving pregnancy-associated uterine rupture after hysteroscopic surgery identified 17 cases that had occurred following hysteroscopic metroplasty [2]. Intraoperative perforation had been reported in most of these cases, and most procedures were performed using intrauterine electrosurgery [4].

We present a case of a recurrent large uterine fundal dehiscence in conscecutive cesarean operations in a patient who had undergone uterine septum resection.

Case

A 35-year-old woman presented at 39 weeks of gestation (Gravida 2, Parity 1) and was admitted on 26 January 2015 to our clinic for an elective cesarean section. Her reproductive history included a septum resection which resulted in uterine perforation (20 March 2012), and one cesarean operation in which a large fundal defect was found and repaired (18 May 2013).

Her genital examination and ultrasound findings were normal. During cesarean section no uterine rupture was evident. A normal 3200 g viable fetus was delivered. After delivery of the palcenta however, the examination of the uterus revealed that there was an aproximately 5 cm large uterine fundal defect (Figure 1).

Figure 1:

The appearance of large fundal defect after removing thin covering serosa.

The defective area was covered with only a small thin transparent membraneous surface which was removed to examine the defect on the fundus of the uterus. The defect was complete including all three layers of uterus.

After identifying the three layers of the uterus, the defects were repaired using 0/0 vicryl^® and 2/0 monocryl^® sutures Figure 2.

Figure 2:

The defect after repair.

The operation was finished without any further complications. Mother and child were discharged in good condition on postoperative day 2.

Discussion

Uterine rupture after hysteroscopic septum resection is a rare complication, and its frequency is reported to be approximately 1–2.7% [5]. Women with septate uterus apply to clinics with late first trimester abortions, or early second-trimester abortions and infertility. The diagnosis of a malformed uterus can be made during a physical examination when obvious anomalies of the vagina and cervix are present, also hysterosalpingography, ultrasonography, magnetic resonance imaging, laparoscopy and hysteroscopy can be used for evaluation of uterine anomalies. Hysteroscopic metroplasty can be performed with electrosurgical or laser energy [6].

Uterine rupture during pregnancy has been reported in case reports in patients who have a history of uterine septum resection. However, recurrent uterine rupture due to hysteroscopic septum resection in pregnancy, is a very rare condition [7].

We present a case report of a patient with recurrent uterine fundal rupture during consequtive pregnancies who had uterine septum resection history due to a large uterine septum.

The authors concluded that as each uterine rupture occurred earlier than the rupture in the previous gestation, a history of uterine rupture during pregnancy should raise suspicion about the possibility of earlier uterine rupture recurrence. This progression suggests that scar tissue formation after surgical repair of each rupture is weaker than that of the previous repair.

Myometrial damage is believed to be the predisposing factor in uterine perforation [8]. Myometrial damage during septum resection is accepted as a major risk factor for uterine perforation or dehiscence during pregnancy.

A deep incision during hysteroscopy is the most common predisposing factor for early rupture [8]. Ludwin et al. used three- or four-dimensional transrectal ultrasonography for hysteroscopic metroplasty to detect the resection depth during the operation and they reported no uterine rupture during pregnancy [6]. We have found no randomized controlled trials on hysteroscopic metroplasty, which may confirm safety. Uterine rupture during pregnancy and use of bipolar or monopolar energy sources in hysteroscopy during septum resection has been shown as risk factors for uterine perforation during pregnancy. The risk factor is primarily the perforation during hysteroscopy or alternatively the excessive incision. Advanced uterine septum resection by hysteroscopy may cause chronic weakness of the uterine wall especially at fundal localizations.

Uterine contractions during pregnancy may also be another predisposing factor for dehiscence. The other theory is that the residual septum may result in the weakness of uterine walls during uterine enlargement. Another explaination about the occurance of recurrent uterine defect is that an anomalous uterus may be congenitaly weakened, although the defect may be repeaired properly.

Sparac et al. reported that a uterine septum consists of a similar amount of muscle tissue compared to the myometrial wall; however, these myometrial fibers are more prone to irregularity than the myometrial wall itself. Additionally, connective tissue in the septum is more flaccid [9]. Ergenoğlu et al. reported uterine rupture during pregnancy with complaints of abdominal pain [10]. Our case was different from their case, as our patient had no complaints of localized pain and uterine rupture was detected during the operation. Uterine rupture during subsequent pregnancies is a late complication, which can be detrimental for both the mother and fetus. Sentilhes et al. reported that hysteroscopic metroplasty increased the risk of uterine rupture during subsequent pregnancies and that recent uterine perforation and the use of electrosurgery also increased this risk [4].

However, these complications cannot be considered as independent risk factors. Electrosurgery increases the risk of thermal myometrial vascular damage and weakening of the tissue, which may cause deep tissue necrosis similar to what is observed during laparoscopic myomectomy.

Although subsequent pregnancies may be normal, the findings suggest that once it has occured, a uterine wall weakness can possibly cause chronic uterine wall defects despite proper repairing.

Although our case presented incidental uterine wall dehiscence during cesarean section, patients who have uterine septum resection history should be followed up carefully during pregnancy. The patient and physician must be aware of possible risk for uterine perforation or dehiscence during pregnancy.