Women who had advanced stage cancers, depending on how much of a tumor is left and if they need chemotherapy, should not get pregnant.
Women who had estrogen-positive cancer and are on tamoxifen should wait until treatment is finished because of the drug's association with birth defects.
Women carrying a genetic mutation that predisposes them to cancer are at higher risk for other kinds of cancer as well, and should be carefully screened before pregnancy.
As for other chemotherapy drugs, if treatment is stopped for an appropriate amount of time, doctors say there won't be any problems.
"There's no risk," Fox Chase's Cristofanilli said. "Women are off chemotherapy, so there's no effect of chemotherapy."
The children of women treated for breast cancer are also at no greater risk for developing cancer in the future.
"Several large studies have confirmed that children born to parents who have had cancer are just as healthy as the non-cancer population," said Gwendolyn Quinn, associate professor at the University of South Florida College of Medicine in Tampa.
As Applegate and Cacioppo proved, many women can get pregnant after breast-cancer treatment, although doctors say there may be issues with fertility, depending on a woman's age and the kind of chemotherapy she's undergoing.
"Some chemotherapy can cause ovarian damage and cause premature menopause," NYU's Roshan said.
Cristofanilli said, "Many women younger than 40 resume their periods after chemotherapy, so there aren't necessarily fertility issues."
Applegate is still cancer-free, and even though she had a double mastectomy that removed all her breast tissue, Roshan said, women in her situation aren't necessarily out of danger.
"If there are still estrogen receptors, there may be a greater risk of recurrence," he said. "If there's no breast tissue, the risk is much lower. But cancer can still metastasize to a lymph node."
Cacioppo is still healthy as well and, despite her initial fears, has no regrets about her decision to get pregnant after her treatment. She now volunteers with a breast-cancer hotline and counsels women who also want to get pregnant after cancer treatment.
"It's really important that women know that there are people like me who have done it," she said.