Chapter 4: From Age to Ageing: ARTs and the Science of ‘Old Eggs’

It is a sunny afternoon and I am talking with a Swiss reproductive biologist. We are in his office, seated at his desk covered with papers and a computer to one side. He starts our discussion by showing me the last FIVNAT report (Limoni, 2012), which collates data from the 25 affiliated Swiss reproductive medicine centres. We are both leaning over the screen of his computer as he selects the graphs that he finds important to show me. The first graph shows how the age of women starting reproductive treatment is getting older, and how the overall number of IVF cycles has steadily increased in recent years. This expert explains to me that the greater importance of the number of treatments is probably linked to more knowledge and wider acceptance of IVF among the public, resulting in people turning to medical assistance more readily. The second graph he comments on for me shows a decrease in success rates when correlated to women's age. He sighs with disappointment saying that, as a biologist, he has never seen a pregnancy after 45 years of age, and that one just has to forget about it. He then explains to me how women are born with a fixed pool of oocytes that starts to deplete at the onset of menarche, and which will be totally exhausted at the menopause. He makes it clear that this pool will be decreasing years before the menopause. As a biologist, he can observe that the number of oocytes that can be retrieved in an IVF cycle, fertilised and implanted, decreases with age. He then relativises this information by explaining that young women sometimes have ovarian failure; sometimes 40-year old women respond very well to hormonal stimulation, which means that they produce more eggs than he would expect for their age. He concludes by saying that there is ‘age itself’, understood here as chronological age, the amount of years passed since one's birth, and ‘physiological age’, which relates instead to the biology of the ovarian reserve.