Endometrial Preparation

Endometrial preparation is simply the process of getting the uterus ready for your embryo transfer. For the embryo to implant, the lining needs to be the right thickness and must be timed correctly with the stage of the embryo being transferred. This applies to both fresh IVF cycles and endometrial preparation for frozen embryo transfer, where the timing between the embryo and the uterine lining is especially important.

In some women, the lining develops well on its own with natural hormones. In others, we support the lining with medicines to ensure it grows to a good, healthy level. The approach depends on how regular your cycles are and what has happened in previous IVF or frozen embryo cycles.

Clinical Protocol for Endometrial Preparation

Once the uterus lining looks good on ultrasound, progesterone is started — this decides the exact day your embryo should be transferred. The goal is to match the “age” of the embryo with the “readiness” of the lining, so the timing is correct for implantation.

If you have regular cycles, sometimes we simply track your natural ovulation and plan the transfer accordingly, without much medication. If cycles are irregular or if the lining has been thin before, a hormone-controlled approach gives us better control and more stability.

How the Best Embryo Transfer Window Is Determined

The embryo is transferred only when the uterus shows the right conditions for implantation. During each scan, the uterine lining is assessed for two key factors:

• Whether the lining is thick enough 
• Whether it has the right pattern for implantation

If the lining is not ready, medication may be adjusted or the cycle allowed more time. When the lining shows optimal thickness and pattern, the embryo transfer date is scheduled.