Making decisions about having children necessitates an understanding of the fertility of both men and women.  Many women wait to have children, whilst working on their careers or education, mistakenly believing that they can delay childbearing until well into their 30's and still have childbearing choices.

A range of things impact a woman's fertility, the most significant of which is age.   A female foetus already contains all the eggs she will ever have for her entire lifetime, so you are born with a finite amount.  As a woman ages, her eggs age as well so both quality and quantity become an issue.

By about the age of 32, a woman's chances of conceiving begin to decline gradually.  At 35, the decline is even more rapid, with the chances of becoming pregnant reducing by 50% by the age of 40.

At age 30, the chance of conceiving in any given month is around 30%.  At 40 this drops to around 5%.

Apart from the reduction in the chances of becoming pregnant, there are other significant risks associated with later pregnancies. A woman over 35 is about 2.5 times more likely to have a stillbirth. This increases to more than 5 times by age 40. Physical risks to the woman increase as well, with higher incidence of gestational diabetes, placenta praevia and placenta abruption, all of which place a significant health burden, and sometimes life threatening risk on the woman.

At the age of 40 a woman's risk of miscarriage is higher than the chance of producing a live baby.

With age declining fertility, the chances of conceiving and delivering a baby is also markedly reduced with assisted reproduction as well.