In case of female infertility, the ovum was rescued and fertilised in vitro where it was allowed to divide, Where should this egg be transferred
at 5-cell stage

Explanation

**Step-by-Step Solution:**

1. **Understanding the Context**: The question discusses a scenario of female infertility where the ovum (egg) is rescued and fertilized in vitro (outside the body). This process is known as In Vitro Fertilization (IVF).

2. **IVF Process**: In IVF, the egg is retrieved from the female and fertilized with sperm in a laboratory setting. This allows for controlled conditions for fertilization and initial cell division.

3. **Development of the Fertilized Egg**: After fertilization, the fertilized egg, now called a zygote, is allowed to divide and develop for a few days. It typically reaches the 5-cell stage within 3 to 5 days.

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