But couples sometimes are hesitant to cancel the cycle because they have so much invested in it, both financially and emotionally. If the couple doesn't cancel the cycle and four or more embryos implant, it's also risky for the newborn babies, who have a high risk of neurological and other complications if they survive. There is a lot of clinical judgment involved. The couple may then choose to selectively reduce the number of fetuses. But emotionally, and for some couples ethically, this is a very difficult and sometimes unacceptable decision.
Many women are also concerned about potential adverse health effects of fertility drugs.
However, the risk of severe hyperstimulation is less than 1 percent, notes Baker. Treatments that have lasted for more than 12 months may slightly increase a woman's risk,says Baker. But if pregnancy results from the treatment, the risk may be diminished because some studies have shown pregnancy to be protective against ovarian cancer. Because a large percentage of patients have not been followed into their 60s, the peak age of ovarian cancer, it will take many years to know the definitive answer. Ironically, some studies have shown that the condition of infertility can slightly increase a womans risk of ovarian cancer.