Placenta percreta after transcervical myomectomy

Introduction

The age at which women give birth to their first child is increasing, contributing to an enhanced risk of developing intrauterine fibroids. Thus, there is an increasing demand for gynecologists to utilize a conservative approach in treating fibroids, with the aim of preserving fertility. The past decade has witnessed highly sophisticated diagnostic and therapeutic technological development for removal of fibroids, and transcervical hysteroscopic and laparoscopic resection is increasingly used in women who want to become pregnant. Furthermore, the conception rate following myomectomy in infertile patients has been reported as high as 57% [6].

Following hysteroscopic myomectomy, the scar in the uterine cavity can be the seat of placental implantation, and in many cases, the placenta is not only adherent but also extends into and through the uterine wall as a percrete placenta (Figure 1) and may cause a peripartum hysterectomy and a severe peripartum hemorrhage.

Figure 1

Ultrasound picture with typical features of percrete placenta praevia.

Arrow A shows the abrupt disappearance of the myometrium (left of arrow), at the point where the placenta becomes percrete. B marks the fetal scull and C the amniotic cavity with the amniotic fluid. Arrow D marks the lining between the percrete placenta and the bladder wall demonstrating absence of myometrium. E is the typical placenta lacunas seen widespread in the percrete placenta. F is the maternal bladder with urine.

In recent years, attempts have been made to leave the placenta in situ with the aim of spontaneous resorption; however, it leads to secondary hysterectomy up until 9 months later in 60% of these cases [3]. Another approach introduced recently is resection of the percrete area and consequently preservation of the uterus. The purpose of this report is to describe the treatment of placenta percreta occurring after hysteroscopic removal of a uterine fibroid and to discuss the benefits of local resection of the percrete placenta and thus preservation of fertility.

Presentation of the case

In 2006, a 31-year-old Norwegian woman was diagnosed with a 9×7 cm intrauterine fibroid. She had tried unsuccessfully to conceive and was initially advised to undergo a hysterectomy. However, she wanted to preserve fertility and was recommended to contact an endoscopic clinic in Oslo, Norway, with experience in treating fibroids.

The primary ultrasound examination showed that the fibroid was submucosal but large with a margin of normal muscularis layer at the serosal side of the uterus, and therefore, a hysteroscopic approach was planned. After treatment with a GnRH analogue, the size of the fibroid was reduced to 7×4 cm, and by hysteroscopic resection, a 158 g fibroid was completely removed (Figure 2).

Figure 2

Ultrasound sonography of the fibroid before and after GnRH analogue, the hysteroscopic view, and the resected fibroid.

The following year, after moving to Copenhagen, Denmark, the woman conceived spontaneously. However, in the 27^th gestational week, she was admitted because of vaginal bleeding. Ultrasound examination showed placenta praevia as well as invasion of the placenta through the myometrium – placenta percreta. A multidisciplinary approach involving an anesthetist, obstetrician, radiologist and the blood bank was planned in order to optimize the timing of delivery, reduce bleeding and if possible preserve her uterus.

Elective cesarian section (CS) in week 34 was scheduled, and in preparation for the surgery, inflatable balloons were placed in the internal iliac arteries by the interventional radiologist. We performed a low transverse incision of the abdominal wall, a transverse uterine incision above the percrete area and delivered a healthy male infant of 2300 g. The balloons were insufflated, the percrete area of the placenta invading the myometrium was resected, and the myometrium sutured. A large sponge was placed in the uterine cavity in order to aid in hemostasis in combination with the sutures in the myometrium, and an abdominal cerclage was applied to ensure hemostasis in the lowest part of the isthmus adjacent to the cervix.

The total blood loss during this procedure was 1900 mL.

In 2010, the patient had a second pregnancy, and the placenta was located on the anterior wall without signs of abnormal invasion. By elective cesarean section at week 37+6, a healthy, 3156 g female infant with a normal Apgar score was delivered. The placenta was located at the anterior wall and was not accrete. Furthermore, in 2013, the patient had a third pregnancy with an anterior placenta and no signs of abnormal invasion. After a normal pregnancy, she delivered a healthy female infant of 3316 g at 37+3 weeks by an uncomplicated planned CS; at the same time, she requested tubal resection.

Discussion

Women with fibroids constitute a heterogeneous group, and the treatment depends on the woman’s age and wishes regarding fertility. As maternal age at the first pregnancy is increasing, more women present with fibroids and infertility.

It is currently discussed, whether it is possible to improve fertility by removal of fibroids [8]. The localization of the fibroid has shown to affect fertility, thus even though there are few properly controlled studies; there is consensus that a submucosal fibroid and fibroids larger than 5 cm, as seen in this case, should be removed in order to improve fertility [5].

In the percrete placenta, the invasion of the myometrium stimulates neovascularization especially in the bladder area, and in the isthmic segment close to the cervix. A mostly safe method when trying to limit bleeding during CS in patients with placenta percreta is occlusion of the internal iliac arteries [7]. In this case, the balloons were placed in the internal iliac arteries. A rare case of pseudoaneurysms, arterial rupture and compromised vascular supply after balloon catherization has been described [1]; meanwhile, it has also been shown that occlusion of the internal iliac arteries is a safe method but that occlusion of the common iliac artery is preferable [4]. Prophylactic use of inflatable balloons in the iliac arteries may reduce the hemorrhage at surgery, but the vesical vessels originate from other branches and uterine tamponade or sandwich technique, where a combination of sutures and an intrauterine balloon (such as Bakri) is used, is necessary as a supplement [2].

A recent review of published cases found that – in general – local resection was associated with fewer complications than a hysterectomy or leaving the placenta in situ for resorption [3]. From a population-based study of accreta, increta and percreta, it seems that you should not try to remove the placenta especially when you aim at hysterectomy [9]. Both the review and the population based study have major weaknesses – and the common weaknesses are that intended mode of operation is not known and that placenta accreta is a heterogeneous condition.

This case emphasizes the importance to always revalidate if a hysterectomy is strictly necessary, when treating fertile women in gynecology and obstetrics, especially in excessive obstetric bleeding, where the traditional approach has been to choose a hysterectomy. The alternative – local resection and compression sutures in a multidisciplinary setting – are much more suitable solutions for a woman wishing to preserve fertility.