43: Vaginal Bleeding

Key Points

• Obtain a pregnancy test in any woman of childbearing age who presents with vaginal bleeding or abdominal pain.

• Risk factors are absent in more than 40% of women who have an ectopic pregnancy.

• Ruptured ectopic pregnancy is a surgical emergency requiring prompt intervention and gynecologic consultation.

• Patients with postmenopausal bleeding should be referred to a gynecologist for endometrial biopsy to exclude malignancy.

Introduction

Menarche, the onset of menstruation, occurs in girls at approximately age 12. Normal menstruation continues until menopause, which occurs on average at age 51. The adult menstrual cycle is 28 days (±7 days), with menstruation lasting 4–6 days. Normal menstrual blood flow is approximately 30–60 mL; >80 mL of bleeding is considered abnormal. Dysfunctional uterine bleeding (DUB) is due to prolonged or excessive estrogen stimulation or ineffective progesterone production. Menorrhagia is an increased volume or duration of bleeding that occurs at the typical time of menstruation. Metrorrhagia is bleeding that occurs at irregular intervals outside of the normal menstrual cycle. Menometrorrhagia is irregular bleeding that is also of increased duration or flow.

Pregnancy must be excluded in women of child-bearing age who present with vaginal bleeding.

Vaginal bleeding complicates 20% of early pregnancies. When bleeding occurs, 50% of patients will have a spontaneous abortion. In the United States, about 2% of all pregnancies are ectopic pregnancies. Mortality in these women is due to shock from intra-abdominal hemorrhage. In postmenopausal women with vaginal bleeding, 10% will be diagnosed with cancer, the majority being endometrial cancer.

Ectopic pregnancy is one of the most important causes of vaginal bleeding. Ectopic pregnancy occurs when a trophoblast implants at a site outside of the endometrium. In most cases, the ectopic site is within the lateral two thirds of the fallopian tube. Other sites include the medial third of the fallopian tube, cornu (junction of the tube and uterus), ovary, fimbria, cervix, and abdomen (Figure 43-1). Risk factors for ectopic pregnancy include a history of salpingitis, use of an intrauterine device, a prior ectopic pregnancy, increased maternal age, use of fertility drugs, and history of tubal ligation. Up to 42% of women with an ectopic pregnancy have no risk factors.

Clinical Presentation

History

A detailed history is essential. Determine the onset of bleeding, the date and duration of the last normal menstrual period, the number of previous pregnancies, and the presence of any prior history of abnormal ...