(b) For successful pregnancy, at what phase of the menstrual cycle an early embryo (up to 3 blastomeres) should be implanted in the Uterus (IUT) of a human female who has opted for Assisted Reproductive Technology (ART)? Support your answer with a reason.
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The luteal phase ensures optimal uterine conditions for embryo implantation due to high progesterone levels.
\begin{itemize} \item Phase: Luteal phase (Days 15-28). \item Rationale: The uterine lining (endometrium) is at its thickest and most vascularized, creating an optimal environment for embryo implantation and subsequent development.\end{itemize}