Obstetrics and Gynecology - A.M. Hromova 2000

Obstetric Hemorrhage
Hemorrhage in the Third Stage of Labor and the Early Postpartum Period
Placental Attachment Anomalies

The term "implantation" refers to the strength of the bond between the chorionic villi and the decidua of the uterine wall. In normal implantation, the chorionic villi are located within the functional layer of the uterine decidua. In some cases, however, the Placenta implants into deeper layers of the uterine wall.

False placenta accreta—known as placenta adherens or adherent placenta—is the most common form, where chorionic villi reside within the basal layer of the decidua due to Atrophy of the spongy layer of the decidua. True placenta accreta also occurs, caused by the partial or complete absence of the spongy layer of the decidua. As a result, the chorionic villi reach the myometrium (placenta accreta), grow completely through it (placenta increta), or invade both the myometrium and the serosal layer of the Uterus (placenta percreta). Placental adherence can be either complete or partial, depending On the surface area of the placenta involved.

This severe condition is typically caused by a history of frequent abortions, pathological labor, or endometritis, which lead to degenerative Changes in the mucous membrane of the uterus. On the other hand, chorionic villi may sometimes penetrate deeper into the uterine wall due to increased activity of Proteolytic Enzymes.

The Clinical presentation of partial false placenta accreta manifests as uterine bleeding in the absence of signs of placental Separation. In cases of complete placenta accreta, bleeding is absent.

The physician's management in the Third Stage of labor should be expectant and active. Expectant management implies that the obstetrician does not interfere with the course of the third stage until signs of placental separation appear. This is because the uterus contracts evenly and rhythmically, allowing the placenta to separate without structural disruption. Any Interference during this period (such as external uterine massage or cord traction) can disrupt the normal process of placental detachment.

Throughout the third stage of labor, the patient's general condition (pulse, Blood pressure, Skin and mucous membrane coloration, Temperature) and well-being are closely monitored, and blood loss is quantified. Typically, signs of placental separation appear within 30 minutes to an hour (most often within 5–15 minutes). If signs of separation are absent and blood loss exceeds physiological limits, active management of the third stage must be initiated via Manual Exploration of the uterine cavity. If partial placenta accreta is detected, manual removal of the placenta is performed under anesthesia. Before the Procedure, the obstetrician prepares their hands and the surgical field. Using the left hand, the labia are parted, while the right hand is folded into a cone shape and introduced along the umbilical cord into the uterine cavity. Locating the edge of the placenta, the physician gradually detaches it from the uterine walls using blunt, sawing motions with the edge of the palm. The placenta is then delivered by gentle traction on the umbilical cord with the external hand, while the intra-uterine hand revises the uterine walls—performing a manual exploration of the cavity and removing any residual placental tissue and membranes. This is achievable in cases of adherent placenta. If there is no bleeding and no signs of placental separation during the third stage of labor for 2 hours in primiparas or 1 hour in multiparas, a Diagnosis of complete placenta accreta is made, and an attempt at manual detachment from the uterine wall is performed. This is feasible in false accreta, but impossible in true accreta (where the placenta cannot be separated from the uterine wall). In such cases, Surgical Treatment (laparotomy and supracervical Hysterectomy) is performed. It is important to bear in mind that women with placenta accreta are at risk of Uterine rupture due to thinning of the uterine wall. Rough handling of the uterus, especially during attempts at piecemeal placental removal in cases of accreta, leads to massive Hemorrhage, hemorrhagic Shock, and DIC syndrome.