‘Sobering’ Study Shows Challenges of Egg Freezing

Claire Evans decided to freeze her eggs six years ago, when she was 36. She had just broken up with her fiancé and was worried that her time to have a baby was running out. A friend, whose own marriage had just ended, suggested the procedure.

She took medications to stimulate her ovaries to overproduce eggs, which were frozen to use later and to have a baby at an age when it would be difficult to become pregnant without medical intervention.

The procedure of egg-freezing is an increasingly popular, but expensive, option for women who want to delay childbirth. But new research documents some caveats: how old a woman is when she freezes her eggs and how many eggs she freezes make a significant difference in whether she will have a baby. Most women who tried to become pregnant, the study found, did not succeed, often because they had waited until they were too old to freeze eggs and had not frozen enough of them.

That note of caution comes from data published this summer in a paper in the...