Pregnancies in women older than 35 are increasing markedly in Western countries.1 Some commentators believe that this demographic shift poses a small or manageable problem as there are compensatory successful fertility treatments. However, it is harder for older women to become and stay pregnant, and outcomes for the mother and child are poorer.2^–5

Age related fertility problems increase after 35 and dramatically after 40. Women have had more opportunity to acquire pelvic infections or develop endometriosis or premature menopause. Body mass index, which rises with age, independently affects fertility and treatment adversely. We do not understand reproductive senescence,^w1 but there are no immediate prospects of treatments to reverse it. Paradoxically, the availability of in vitro fertilisation (IVF) may lull women into infertility while they wait for a suitable partner and concentrate on their careers and achieving security and a comfortable living standard. But this expensive, invasive treatment has high failure rates (more than 70% of women undergoing a cycle of IVF do not achieve a live birth—more than 90% when older than 40).6 It brings extra risks of multiple …