Third Trimester Bleeding

Introduction

• Description: Vaginal bleeding during the third trimester of pregnancy (generally >25–27 weeks gestation). Vaginal bleeding should be seen as a symptom, rather than a diagnosis. Most often, the blood is of maternal origin.

• Prevalence: Bleeding complicates 4%–5% of pregnancies.

• Predominant Age: Reproductive age.

• Genetics: No genetic pattern.

• ETIOLOGY AND PATHOGENESIS

• Causes: Cervical dilation, premature separation of a part or all of the placenta, abnormal placentation (location or character).

• Risk Factors: Trauma (including physical abuse), labor, multiparity, advanced maternal age, smoking, cocaine use, multiple gestation, prior placenta previa and prior abortion.

Signs and Symptoms

• Painless vaginal bleeding after 25–27 weeks of gestation.

• Uterine hyperactivity possibly present when associated with a placental abnormality (20%).

• When bleeding is heavy—hypotension, tachycardia, orthostasis, syncope.

Diagnostic Approach