In Vitro Fertilization

Abstract
A 37-year-old woman who has never been pregnant and her 40-year-old husband have been attempting to conceive a child for the past 3 years. An infertility evaluation has shown no cause for the difficulty. She is ovulating regularly, and a hysterosalpingogram shows that her reproductive tract is anatomically normal. He has a normal sperm count; he has not fathered any children. They are frustrated and want to proceed with in vitro fertilization. What should you advise?