In which part of the uterus does most implantation occur?

Most implantation occurs in the upper posterior fundal portion of the uterus. This area is highly vascular and provides the optimal environment for the developing embryo to establish a connection with the maternal blood supply. The fundal region, being the highest point in the uterine cavity, offers a thick lining rich in nutrient supply, which is crucial for the implantation process.

Implantation in this area typically allows for the best outcomes in terms of maternal-fetal blood flow and nutrient exchange, which are essential for the ongoing development of the embryo. Additionally, the upper posterior area is away from the cervix, reducing the risk of complications such as placenta previa, where the placenta attaches near or over the cervical opening.

In contrast, the other areas of the uterus, such as the lower segment and near the cervix, are less favorable for implantation due to thinner endometrium and potential complications associated with cervical involvement.