In the United States, the mean age of a woman having her first child has risen over the past several decades. Although there are many factors that could be contributing to this change, it does impact how we approach and counsel our patients about their fertility potential and pregnancy outcomes.
Females are born with the oocytes they will use during their lifetime and this number continues to drop over time. They have 1-2 million oocytes at birth, dropping to 400-500,000 by puberty and only ~1,000 by the time she is menopausal. In addition, the genetic quality of her oocytes decreases with age as these oocytes go through the final stages of meiosis – for a woman >42 years of age, >90% of her oocytes will be aneuploid. Therefore, even though she may still be menstruating regularly, the likelihood of that oocyte being euploid and it resulting in a live birth is extremely low. Her rate of miscarriage will be >40% per pregnancy and her chance of pregnancy per cycle will be 5% or less.
Given these changes in a woman’s fertility potential with age and increasing age with first pregnancy, sometimes our patients do not realize their fertility potential by the time they are ready to start building their families. And in some situations, it is already too late… Each one of their clinic visits presents an opportunity for us to assess their desire for childbearing in the near or distant future and their family-building goals.
One way to look at it is – fertility care – not just infertility.
We live in a unique time where fertility preservation techniques, such as oocyte vitrification, have been refined and present the opportunity for women to delay childbearing if they so choose – leaving potential to conceive at a later age. This allows women more freedom and flexibility to have their first child when they are ready. In addition, for those desiring multiple children, seeking treatment sooner and having embryos frozen at an earlier age increases their chance of live birth per embryo as compared to seeking fertility treatment at a later age.
For those women currently trying to conceive, but having difficulty, certain situations also warrant an earlier referral than the usual 6-12 months. These women include but are not limited to, those with ovulatory dysfunction, severely diminished ovarian reserve (i.e., very low AMH), tubal dysfunction, or male factor. In situations where there is a delay to care, sometimes it is too late for women to use autologous oocytes for conception.
Every woman is unique in her fertility goals, and the conversation is not always easy to broach with patients. However, educating our patients on their fertility potential and presenting options for family building earlier on can bring them one step closer to their ideal family size.