Can the embryo implant and be sustained in the uterus?
Even if the sperm and egg are able to unite, the embryo may have difficulty implanting and sustaining itself in the uterus. Your doctor may also obtain a tissue sample, often referred to as an endometrial biopsy, from the uterine lining to see if it is developing properly or a conduct an ultrasound to see how thick the uterine lining is.
