**Question:** Dose of anti D in ectopic pregnancy -

A. 500 IU
B. 1000 IU
C. 2000 IU
D. 4000 IU

**Core Concept:**
Ectopic pregnancy is a type of pregnancy in which the fertilized egg implants outside the uterine cavity. In cases of hemoperitoneum due to ruptured ectopic pregnancy, administration of anti-D immunoglobulin is indicated for Rh-negative females. Anti-D helps in preventing the formation of anti-D antibodies in the bloodstream, thereby reducing the risk of future hemolytic disease of the newborn.

**Why the Correct Answer is Right:**
The correct answer is **C. 2000 IU** of anti-D immunoglobulin. The dose of anti-D is determined based on the severity of the hemoperitoneum. In mild cases, a lower dose may suffice, while a higher dose is required for severe cases. The 2000 IU dose is considered sufficient for most cases of hemoperitoneum due to ruptured ectopic pregnancy.

**Why Each Wrong Option is Incorrect:**

A. **500 IU**: A lower dose may not be sufficient in severe cases of hemoperitoneum, leading to inadequate prevention of anti-D antibodies and potential future hemolytic disease of the newborn.

B. **1000 IU**: Although higher than option A, this dose may still be insufficient for severe cases, as mentioned earlier.

D. **4000 IU**: A higher dose is not necessary, as the administration of anti-D is targeted to achieve a therapeutic concentration without causing adverse effects like agglutination of red blood cells.

**Clinical Pearl:**

In cases of ectopic pregnancy, administering anti-D immunoglobulin is crucial to prevent hemolytic disease of the newborn. However, the choice of dose must be based on the severity of hemoperitoneum. This ensures the right balance between efficacy and potential adverse effects from a higher dose. Always consider the individual patient's condition and consult a specialist before administering anti-D immunoglobulin to avoid any complications.