Conservative management of abnormally invasive placenta: four case reports


  • The authors have stated explicitly that there are no conflicts of interest in connection with this article.


Angela Ramoni, Department of Obstetrics and Gynecology, Innsbruck Medical University, Innsbruck, Austria, Anichstraße 35, 6020 Innsbruck, Austria. E-mail:


Prenatal diagnosis of placenta increta and percreta is essential to avoid potentially life-threatening hemorrhage by optimizing peripartal management. Invasive placentation presents significant challenges at cesarean section even for highly skilled surgeons. In the four cases of placenta increta/percreta presented here we tried to avoid hysterectomy by leaving the placenta behind and tried to accelerate regression of placental tissue by administering methotrexate. The outcome in each of the four women was different, but no major bleeding occurred in any of the cases. Close follow-up for many weeks is mandatory.








The incidence of abnormally invasive placentation is rising, primarily due to the increasing rate of cesarean deliveries. Massive, potentially life-threatening blood loss during delivery is the most feared complication. Prenatal diagnosis via ultrasound, followed by appropriate peripartum management of this condition, may help reduce morbidity and mortality. There are different approaches in managing delivery in placenta percreta: cesarean section with hysterectomy or resection of parts of the uterus vs. uterus-conserving surgery leaving the placenta behind and giving methotrexate. Nevertheless, the optimal treatment has not yet been determined [1, 2].

We report four cases of placenta percreta (Table 1) in which we tried to avoid hysterectomy and partial resection of the invaded bladder. Follow-up was different for each of the four patients, but none of the women experienced severe peripartum hemorrhage.

Table 1. Outcome of four patients with placenta percreta
PatientPrevious cesarean sectionDiagnosisClinical courseUnits of packed red blood cells
  1. G, gravida; P, para.

24y G4/P22Placenta previa totalis percreta infiltration of the bladderFebrile infection day 62 successfully treated with antibiotics; placenta vanished after 6 months0
29y G7/P31Placenta previa totalis percreta infiltration of the bladderFebrile infection with bleeding day 58; vaginal removal of placenta and insertion of Bakri-balloon for 12 h2 on day 59
34y G9/P63Placenta previa totalis percreta infiltration of the bladderBleeding on day 18 necessitating hysterectomy; no bladder lesions4 on day 18
29y G2/P21Placenta previa totalis percreta infiltration of the bladderVaginal removal of placenta on day 59, bleeding necessitating hysterectomy no bladder lesions6 on day 59

Case reports

Case 1

24 years old, gravida (G)4/para (P)2, two previous cesarean sections (last 2008).

The patient presented with vaginal bleeding in January 2010 in week 27 of pregnancy. Ultrasound was suggestive of placenta previa on the anterior uterine wall with loss of the myometrial echolucent stripe and protrusion of the placenta into the bladder and large echolucencies in the placenta. Suspected infiltration of the posterior wall of the bladder was verified by cystoscopy. Fetal lung maturity was achieved with steroids (betamethasone). There was no further vaginal bleeding during tocolysis.

The cesarean section was planned and performed in the week 37 via a vertical skin incision under general anesthesia. The upper end of the placenta was sonographically marked on the uterine wall, and the fetus was delivered via a vertical fundal uterine incision. The umbilical cord was ligated. No uterotonic medication was given. The uterine incision was closed with a double-layer technique. Both uterine arteries were closed with vascular clips as a prophylactic procedure. Preoperatively, the patient received a transfusion of 2 units of red blood cells due to anemia [hemoglobin (Hb) 9 g/dL]. No other transfusions were necessary; postoperative Hb level was 12 g/dL. Prophylactic antibiotic treatment (cephalosporin) was started intraoperatively. Methotrexate (1 mg/kg) was given i.m. weekly (nine courses), starting one week after cesarean section on the ward.

Outpatient management two weeks after cesarean section consisted of monitoring vaginal swab, C-reactive protein, red blood cell count, ß-human chorionic gonadotropin and weekly ultrasound. The antibiotic regimen was adjusted weekly according to the result of the vaginal swab (antibiogram). Sonograms showed no fluid in the uterine cavity, with the placenta becoming more echodense. The patient reported intermittent vaginal bleeding and expulsion of small pieces of tissue.

Two months after cesarean section the patient presented with fever (38.0°C) and rising C-reactive protein level (25 mg/dL). Inpatient management for one week consisting of parenteral antibiotic treatment with fosfomycin and ampicillin/clavulan successfully resolved this complication.The placenta vanished completely within six months (Fig. 1).

Figure 1.

Case 1: ultrasound images showing total resorption of placenta.

Case 2

29 years old, G8/P3, one cesarean section 2006 (due to fetal growth restriction).

The patient presented with vaginal bleeding and contractions in June 2010 in week 32 of pregnancy. Ultrasound and magnetic resonance imaging showed a total placenta previa with invasion of the bladder.

Due to recurrent vaginal bleeding the cesarean section had to be done in week 33 using the same procedure as in case 1. No blood transfusion was necessary. Prophylactic antibiotic treatment was started intraoperatively (cephalosporin). In this case, the methotrexate therapy was started seven days after cesarean section in a weekly regime (1 mg/kg i.m., six courses). The outpatient surveillance was done as in the first case. The patient reported intermittent vaginal bleeding and expulsion of small pieces of placental tissue.

Two months after the cesarean section the patient was hospitalized due to fever (39°C), vaginal bleeding and endometritis. Placental tissue was removed manually under general anesthesia, and an intrauterine postpartum balloon (Bakri) was subsequently inserted for 12 h due to severe bleeding. The balloon was filled very carefully during sonographic visualization to minimize the risk of rupture of the infiltrated myometrium. The Hb level decreased from 12.8 to 8.8 g/dL after the intervention. No further complications were observed (Figure 2).

Figure 2.

Case 2: ultrasound images showing infiltration of external bladder wall.

Case 3

34 years old, G9/P6, three vaginal births, three cesarean sections (last 2007).

The patient presented in March 2011 in week 32 of pregnancy with vaginal bleeding caused by placenta percreta with invasion of the bladder. Iron deficiency and anemia (Hb 9.2 g/dL) were treated with infusion of iron-carboxymaltose (1000 mg), which produced no increase in Hb level. Because of persistent bleeding and after transfusion of 2 units of red blood cells, a cesarean section was performed in week 34 of pregnancy leaving the placenta in situ. Prophylactic antibiotic treatment with amoxicillin/clavulan was started intraoperatively. Methotrexate (1 mg/kg) was commenced two days after cesarean section and administered twice weekly. Outpatient monitoring was impossible due to patient non-compliance.

Eighteen days after cesarean section the patient presented with severe vaginal bleeding and abdominal pain. Parts of the placenta were visible in the cervix. The placenta was removed digitally, but severe bleeding occurred and could not be stopped. Total abdominal hysterectomy was performed without needing to resect parts of the bladder wall. The histology showed placental invasion deep into the myometrium with partly viable placental tissue. No further complications were observed.

Case 4

29 years old, G2/P1, one cesarean section (breech position, 2009).

The patient presented with spontaneous vaginal bleeding caused by total placenta previa invading the bladder wall in October 2011 in week 28 of pregnancy. A cesarean section had to be performed in week 31 because of persistent vaginal bleeding despite tocolysis and bedrest. As the uterine arteries were not accessible, the main trunks of both internal iliac arteries were ligated as a prophylactic procedure to prevent heavy bleeding. No transfusion was necessary, and the postoperative Hb was 11.6 g/dL. Methotrexate (1 mg/kg) i.m. was commenced three days after cesarean section, and was administrated three times per week. After six cycles of methotrexate, an attempt was made to remove the placenta digitally under sonographic visualization (59 days after cesarean section). Due to severe vaginal bleeding, we performed a total abdominal hysterectomy immediately without need to resect the bladder wall. The patient received a transfusion of 6 units of red blood cells. No further complications were observed.


The prevalence of an abnormally invasive placenta far into the uterine muscle or even into neighboring structures is increasing, mainly due to the rising rate of cesarean deliveries, and may be associated with massive blood loss at delivery [2]. Ultrasonography is the primary imaging modality for diagnosing placenta percreta, but reliable differentiation of true infiltration of the bladder wall is difficult. In cases of posterior placenta accreta, magnetic resonance imaging may be superior to ultrasonography [3, 4].

Appropriate management should consider leaving behind the placenta and preserving the uterus, not only in patients who desire to remain fertile [2, 5-7]. Massive hemorrhage and mutilating surgery involving resection of parts of the bladder in the case of infiltrating placenta may be avoided. Additional procedures include prophylactic ligation of uterine arteries (or internal iliac arteries) and treatment with methotrexate.

In our cases both uterine arteries were ligated to prevent severe bleeding. Only in case 4 were both internal iliac arteries ligated, as uterine arteries were not accessible. Nevertheless, severe bleeding may occur via collateral vessels and having an interventional radiologist skilled in carrying out embolizations standing by, might be valuable.

There is controversy in the literature as to whether methotrexate should be used in the treatment of invasive placentation. However, only a small number of case reports have been published. Methotrexate is effective against trophoblastic proliferation, but there are no studies comparing methotrexate vs. no methotrexate in the treatment of placenta accreta [8-11]. Some authors have argued that there is no further cell division of placental tissue after delivery of the fetus, and therefore methotrexate may be of no value. Also, the general immunosuppressive effect must be kept in mind. However, vital placental tissue may be present even weeks after a cesarean section (case 3).

Depending on the result of the weekly vaginal swab, the type of antibiotic was adjusted to limit the amount of resistant microorganisms. Spontaneous placental resorption may occur later, and delayed hysterectomy can be performed under optimized conditions. Conservative management carries the risk of intrauterine infection and delayed hemorrhage. Patients must be informed of the importance of close and consistent outpatient follow-up for many weeks.