A clinical review in the November 2008 BMJ (British Medical Journal) recommends that nurses and physicians counsel patients younger than 40 and their families about fertility preservation before cancer treatment begins. Men can have sperm samples cryopreserved. Women and their male partners can produce embryos for freezing via in vitro fertilization (IVF). For women with estrogen receptor-positive breast cancer, safer IVF methods are being developed that don't require increasing the amount of estrogen in the body. Strategies for single women, such as freezing just the egg cells alone or having ovarian tissue frozen for later reimplantation, are still experimental. Hospital ethics committees should address fertility preservation in children and teens.