Time is of the essence: personalized prediction of reproductive time span to optimize life goals

Regina is a 38-year-old woman who has been trying to conceive for about a year. She married late in life and started trying to conceive shortly thereafter. She is in good health, with no medical problems, and has had fairly regular menstrual cycles; however, she notes that the length of her cycle has gotten shorter over the past 2 to 3 months and is now occurring every 25 days. She has used an over-the-counter "fertility" test that assesses ovarian reserve by urinary follicle-stimulating hormone levels, which indicated that she has low fertility. She decided to seek medical help.