ABSTRACT
INTRODUCTION One in seven couples in the UK seek medical help for infertility, and of these, about half will require treatment with assisted conception. The increase in infertility rates in recent years is most likely because of a combination of factors including many women delaying the age at which they start trying for a family, declining sperm counts, and a rise in the incidence of sexually transmitted diseases such as chlamydia. The number of firsttime mothers less than 25 years has halved over the last 20 years while it has trebled in those over 35 years. Approximately 30% of couples suffer from female factor infertility, the remainder being due to male factors or unexplained. However, of those that are unexplained, an increasing proportion is likely to be because of decreasing oocyte quality and ovarian reserve in older women. The current trend of increasing subfertility rates is also linked with obesity, leading to polycystic ovarian syndrome (PCOS) and hence anovulatory subfertility.
