In general, the success of frozen-thawed embryo transfer procedures depends on three factors:

The quality and survival of the frozen-thawed embryos. In general, we only freeze good quality embryos so the current rate of survival is greater than 90%.
The age of the woman who produced the eggs. In patients under the age of 37, the chances of pregnancy with frozen-thawed embryos are similar to a pregnancy with fresh embryos.
In patients 37 years or older, pregnancy chances with frozen-thawed embryos decline in conjunction with declining fertility in general, but still can be quite good. As always it is best to discuss a woman’s individual situation with their physician.
The status of the uterus in the woman receiving the embryos. A healthy endometrial lining free of any interfering fibroids or polyps provides a sound environment for embryo implantation.