Michele K. Bourquin, an account executive from Atlanta, was 36 and divorced when she first looked into freezing her eggs.

“I knew I wasn’t getting any younger, and my eggs were aging,” Ms. Bourquin said.

So she visited a doctor who gave her a blood test that’s often used to check a woman’s egg supply. It works by looking for anti-Müllerian hormone, or AMH, which is secreted by growing follicles, the sacs that house each egg.

The results were not good, she was told. Her AMH was too low and her follicle stimulating hormone level was too high, both indicators of diminished egg quantity. In other words, it would most likely take multiple procedures to bank enough eggs.

At about $15,000 each, the cost was prohibitive, and her insurance didn’t cover egg freezing or fertility treatments. A nurse suggested that she use donor eggs.