THIRD TRIMESTER BLEEDING Rukset Attar, MD, PhD Department of Obstetrics and Gynecology

THIRD TRIMESTER BLEEDING Obstetric causes Obstetric causes Nonobstetric causes Nonobstetric causes

Obstetric Causes Bloody show Bloody show Placenta previa Placenta previa Abruptio placentae Abruptio placentae Vasa previa Vasa previa Disseminated intravascular coagulopathy (DIC) Disseminated intravascular coagulopathy (DIC) Uterine rupture Uterine rupture Marginal sinus bleed Marginal sinus bleed

Nonobstetric Causes Cervical cancer or dysplasia Cervical cancer or dysplasia Cervicitis Cervicitis Cervical polyps Cervical polyps Cervical eversion Cervical eversion Vaginal laceration Vaginal laceration Vaginitis Vaginitis

Almost all of the blood loss from placental accidents is maternal, some fetal loss is possible, particularly if the substance of the placenta is traumatized. Bleeding from vasa praevia is the only cause of pure fetal hemorrhage but fortunately is rare. If fetal bleeding is suspected, the presence of fetal hemoglobin can be confirmed by elution or electrophoretic techniques

İnitial Evaluation Two principles in the investigation of third-trimester hemorrhage must be followed Any woman experiencing vaginal bleeding in late pregnancy must be evaluated in a hospital capable of dealing with maternal hemorrhage and a compromised perinate A vaginal or rectal examination must not be performed until placenta previa has been ruled out - Vaginal or rectal examination is extremely hazardous because of the possibility of provoking an uncontrollable, catastrophic hemorrhage

İnitial Evaluation Life-Threatening Hemorrhage Associated with Hypovolemic Shock Blood Transfusion Vasoactive Drugs Nonemergency Bleeding History and Abdominal Examination Laboratory Evaluation- blood type, cross match for 2- 6 units, complete blood count including platelet count, baseline coagulation studies-PT-aPTT,,D and dimer and fibrin split products if abruptio placents ia suspected Vaginal Examination- if Pl. Previa and vasa previa are excluded Laboratory evaluation should include blood type and cross-match for 2–6 units, depending on the hemodynamic status, as well as a complete blood count with platelets and baseline coagulation status (prothrombin time and partial thromboplastin time). D -Dimer or fibrin split products are useful when abruptio placentae is suspected

İnitial Evaluation Ultrasound Examination Laboratory evaluation should include blood type and cross-match for 2–6 units, depending on the hemodynamic status, as well as a complete blood count with platelets and baseline coagulation status (prothrombin time and partial thromboplastin time). D -Dimer or fibrin split products are useful when abruptio placentae is suspected

Management of Bleeding The 3 general management options are immediate delivery, continued labor, and expectant management, depending on the diagnosis

Premature Separation of the Placenta (Abruptio Placentae, Marginal Sinus Bleed) Premature separation of the placenta is defined as separation from the site of uterine implantation before delivery of the fetus (approximately 1 in 77–89 deliveries). The severe form (resulting in fetal death) has an incidence of approximately 1 in 500–750 deliveries

Premature Separation of the Placenta (Abruptio Placentae, Marginal Sinus Bleed) Two principal forms of premature separation of the placenta can be recognized, depending on whether the resulting hemorrhage is external or concealed (Fig 20–2). In the concealed form (20%), the hemorrhage is confined within the uterine cavity, detachment of the placenta may be complete, and the complications often are severe. Approximately 10% of abruptions are associated with clinically significant coagulopathies (disseminated intravascular coagulation [DIC]), but 40% of those severe enough to cause fetal death are associated with coagulopathy. In the external form (80%), the blood drains through the cervix, placental detachment is more likely to be incomplete, and the complications are fewer and less severe. Occasionally, the placental detachment involves only the margin or placental rim. Here, the most important complication is the possibility of premature labor.

Premature Separation of the Placenta (Abruptio Placentae, Marginal Sinus Bleed) Etiology The exact causes of placental separation are often difficult to ascertain, although there are a number of predisposing and precipitating factors. A common predisposing factor is previous placental separation. Following 1 episode, the incidence of recurrence is 10–17%. Following 2 episodes, the incidence of recurrence exceeds 20%. The hypertensive states of pregnancy are associated with 2.5–17.9% incidence of placental separation.

Premature Separation of the Placenta (Abruptio Placentae, Marginal Sinus Bleed) In abruptio placentae extensive enough to cause fetal death, approximately 50% of cases are associated with hypertensive states of pregnancy. Approximately half of these cases have chronic hypertension and half pregnancy-induced hypertension. Other predisposing factors include advanced maternal age, multiparity, uterine distention (eg, multiple gestation, hydramnios), vascular disease (eg, diabetes mellitus, systemic lupus erythematosus), thrombophilias, uterine anomalies or tumors (eg, leiomyoma), cigarette smoking, alcohol consumption (> 14 drinks per week), cocaine use, and possibly maternal type O blood..

Premature Separation of the Placenta (Abruptio Placentae, Marginal Sinus Bleed) Precipitating causes Circumvallate placenta, trauma (eg, external or internal version, automobile accident, abdominal trauma directly transmitted to an anterior placenta), sudden reduction in uterine volume (eg, rapid amniotic fluid loss, delivery of a first twin), abnormally short cord (usually only a problem during delivery, when traction is exerted on the cord as the fetus moves down the birth canal), and increased venous pressure (usually only problematic with abrupt or extreme alterations)

Placenta Previa Spotting during first and second trimesters. Sudden, painless, profuse bleeding in third trimester. Initial cramping in 10% of cases.

Placenta Previa Placenta previa is encountered in approximately 1 in 200 births, but only 20% are complete (placenta over the entire cervix). Approximately 90% of patients will be parous. Among grand multiparas the incidence may be as high as 1 in 20.

Placenta Previa The incidence of placenta previa is increased by multiparity, advancing age, and previous cesarean delivery. Thus, possible etiologic factors include scarred or poorly vascularized endometrium in the corpus, a large placenta, and abnormal forms of placentation such as succenturiate lobe. The incidence of placenta previa is slightly higher in multiple gestation. A cesarean section scar triples the incidence of placenta previa. Another contributory factor is an increased average surface area of a placenta implanted in the lower uterine segment, possibly because these tissues are less well suited for nidation..

Placenta Previa Complete marginal

Uterine Atony Extensive infiltration of the myometrial wall with blood may result in loss of myometrial contractility. If, as a result, bleeding from the placental bed is not controlled, hysterectomy may be necessary. If future childbearing is an important consideration, bilateral ligation of the ascending branches of the uterine arteries should be accomplished before resorting to hysterectomy. Not only will blood flow be reduced, but the relative ischemia produced may result in a satisfactory contraction of the damaged uterus. If ligation of the uterine vessels proves ineffective, bilateral ligation of the hypogastric arteries, reducing arterial pressure within the uterus to venous levels, may effect hemostasis. Following ligation of either the uterine or hypogastric arteries, collateral circulation should be adequate to preserve uterine function, including subsequent pregnancies. A relatively new approach to uterine atony is the B-Lynch suture. This technique involves mechanical involution of an atonic uterus with chromic suture, mimicking the hemostasis obtained with bimanual compression.

Rupture of the Uterus Fetal heart rate abnormalities. Increased suprapubic pain and tenderness with labor. Sudden cessation of uterine contractions with a "tearing" sensation. Vaginal bleeding (or bloody urine). Recession of the fetal presenting part.

Rupture of the Uterus Risk factors for uterine rupture include history of hysterotomy (cesarean section, myomectomy, metroplasty, cornual resection), trauma (motor vehicle accident, rotational forceps, extension of a cervical laceration), uterine overdistention (hydramnios, multiple gestation, macrosomia), uterine anomalies, placenta percreta, and choriocarcinoma.