Ectopic pregnancy
A fertilized ovum implants outside the endometrial cavity, almost always in the fallopian tube, and is the leading cause of maternal death in the first trimester. Diagnosis rests on quantitative beta-hCG paired with transvaginal ultrasound, and management branches immediately on hemodynamic stability.
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What this article covers
- Overview
Definition: implantation of a fertilized ovum at a site other than the endometrial cavity, most often within the fallopian tube.
- Epidemiology
Frequency: occurs in roughly 1-2% of all pregnancies, higher after a prior ectopic pregnancy.
- Risk factors
Pelvic inflammatory disease: the most common cause of the tubal scarring that predisposes to ectopic implantation.
- Pathophysiology
Impaired ovum transport: scarring, adhesions, or altered ciliary/muscular function from PID, surgery, endometriosis, or congenital anomaly traps the fertilized ovum before it reaches the endometrial cavity.
- Clinical features
Unilateral lower abdominal or pelvic pain: the hallmark symptom, often with focal adnexal tenderness on bimanual exam; frequently mistaken clinically for appendicitis when right-sided.
- Differential diagnosis
Spontaneous abortion (threatened, inevitable, or incomplete): also presents with first-trimester bleeding and cramping, but ultrasound shows an intrauterine gestational sac or products of conception…
- Diagnosis
How the diagnosis is established: confirmed by a positive beta-hCG together with transvaginal ultrasound showing no intrauterine pregnancy and either a visualized extrauterine sac/embryo or a complex…
- Management
First, assess hemodynamic stability and peritoneal signs.
- Complications
Tubal rupture with hemoperitoneum: the most serious complication; a surgical emergency causing hypovolemic shock and, if unrecognized, maternal death.
- Prognosis
Favorable with prompt diagnosis and treatment: maternal mortality is low when ectopic pregnancy is recognized and treated before rupture.
- Prevention
Early pregnancy confirmation and dating: obtain a pregnancy test at the time of a missed period and, in any patient with risk factors (prior ectopic, prior tubal surgery, known PID, IUD in place with…
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Related articles
- Pregnancy of unknown location
A positive pregnancy test with no gestational sac seen on transvaginal ultrasound in the uterus or adnexa is a pregnancy of unknown location, and every case is managed as a possible ectopic pregnancy until serial beta-hCG and repeat ultrasound establish a final diagnosis. It is a transient diagnostic state, not a disease entity, resolved by trending hCG against the discriminatory zone and the expected rise of a viable intrauterine pregnancy.
- Spontaneous abortion
Spontaneous abortion is loss of an intrauterine gestation before 20 weeks, classified by cervical os status and ultrasonographic findings into threatened, inevitable, incomplete, complete, missed, and septic subtypes. Diagnosis rests on transvaginal ultrasonography plus serial beta-hCG, and management ranges from expectant care to uterine evacuation, with septic abortion treated as a surgical and antibiotic emergency.
- Pelvic inflammatory disease
Pelvic inflammatory disease is an ascending polymicrobial infection of the upper female genital tract, most often caused by Neisseria gonorrhoeae, Chlamydia trachomatis, or Mycoplasma genitalium, diagnosed clinically on uterine, adnexal, or cervical motion tenderness. Most women are treated as outpatients with a single dose of ceftriaxone plus 14 days of doxycycline, while parenteral cefotetan or cefoxitin plus doxycycline, or clindamycin plus gentamicin, is reserved for hospitalized patients, with tubo-ovarian abscess and infertility among the major complications of delayed treatment.
- Acute appendicitis
Acute appendicitis is luminal obstruction and infection of the vermiform appendix presenting as migratory periumbilical-to-right-lower-quadrant pain, diagnosed by the classic history and exam plus confirmatory imaging (CT in adults, ultrasound or MRI in children and pregnancy), and treated with prompt appendectomy or, in selected uncomplicated cases, antibiotics alone.
- Nephrolithiasis
Nephrolithiasis affects 7-11% of the US population, most often as calcium oxalate stones, and presents as colicky flank pain radiating to the groin with hematuria. Noncontrast CT confirms the diagnosis and stone size drives management: hydration, NSAID/opioid analgesia, and alpha-blocker expulsive therapy for stones under 10 mm, urologic intervention for larger, infected, or obstructing stones.