Doctors at the University of Goteborg in Sweden are waiting to see whether or not they can call two uterus transplant surgeries a success after two women donated the organs to their daughters. Doctors say they are optimistic after the procedures went smoothly, but that the real test will be whether the women can carry healthy babies to term.

The surgeries aren’t the first of their kind, but a similar one in Saudi Arabia led to the uterus being removed due to a blood clot. Doctors say the risk of complications is greatly lessened when the donor is a blood relative of the recipient, but with something as fragile as a womb, anything can happen.

The procedure, if successful, could prove to be life-changing for women who can’t have babies on their own.

“There’s no doubt this will be a pioneering step if it’s been successful,” said Scott Nelson, chair of obstetrics and gynecology at the University of Glasgow, Scotland. “At present, the only option for these women is to have a surrogacy, i.e. having their embryos implanted into another woman.”

There are significant risks involved with the transplant, however, such as the womb having fewer blood vessels than would be found in the patient’s own. This could lead to insufficient development of the fetus. Also, if one of the new recipients does become pregnant, she will only be allowed two full-term pregnancies with the organ in order to stop the mandatory use of anti-rejection drugs (which stop the body from rejecting the foreign organ).

Still, such a significant step in science could make a huge impact in the world of infertility, and many are hopeful that the results will be better than expected.