Abnormally invasive placenta (AIP): pre-cesarean amnion drainage to facilitate exteriorization of the gravid uterus through a transverse skin incision

The number of pregnant women with abnormally invasive placenta (AIP) including clinical relevant placenta increta and percreta has markedly increased with a reported incidence of as high as one in 731, By 2020 in the United States, there will be an estimated 4504 new cases of AIP and 130 AIP-associated maternal deaths annually. The preoperative diagnosis and operative management of AIP is challenging. In a planned cesarean delivery, a vertical lower abdominal skin incision is widely used in order to have enough space to perform a hysterotomy above the cranial edge of the placenta to avoid significant fetal and/or maternal hemorrhage. We have used preoperative drainage of the amniotic fluid after epidural anesthesia and immediately before a planned cesarean delivery through a transverse skin incision in five patients with AIP of the anterior uterine wall. With less uterine volume, exteriorization of the gravid uterus is easily performed through a transverse laparotomy. The combination of amnion drainage, transverse laparotomy and exteriorization of the gravid uterus facilitates identification of the exact site of placental implantation, provides adequate space for performing fundal or high anterior or even posterior uterine wall incisions and to deliver the fetus safely while minimizing the risk of placental separation and subsequent uncontrolled blood loss. Furthermore, this technique provides the chance to leave the untouched placenta in situ or to remove the placenta in toto with a uterine wall segment.