Ectopic Pregnancy
An ectopic pregnancy occurs when a fertilized ovum implants outside the endometrial cavity. The most common site is the fallopian tube (ampulla). It remains the leading cause of pregnancy-related maternal death in the first trimester.
Clinical Triad
- Abdominal pain (often unilateral)
- Amenorrhea (followed by abnormal vaginal bleeding)
- Adnexal tenderness on examination
Diagnostic Approach
| Method | Key Finding |
|---|---|
| β-hCG | Suboptimal rise (less than 35–53% increase in 48 hours) or plateau. |
| Transvaginal US | Empty uterus with an adnexal mass. “Discriminatory zone” (hCG level > 1500–2000 IU/L should visualize IUP). |
High-Yield Exam Pearl:
- Medical Management: Methotrexate is the treatment of choice in stable patients who meet strict criteria (no rupture, small mass, low hCG).
- Surgical Management: Salpingostomy or salpingectomy (gold standard for ruptured cases or hemodynamically unstable patients).
- Rh Status: Always administer Anti-D immunoglobulin to Rh-negative women to prevent future alloimmunization.