The Link Between Age, Egg Quality, and Miscarriage
Every day we see patients in our clinic who have experienced loss in the form of a miscarriage. Miscarriage is more common than most people realize. It can occur in as many as one in four women in their lifetime. Evaluation of a couple having miscarriages focuses on anatomic, genetic, immune, and hormonal issues that can be detected in a couple. However, before testing, I warn patients that most often the tests come back normal. Hearing that we will most likely not find a reason for the miscarriage/s can be frustrating for a couple.
The most common cause of first trimester (in the first 12 weeks of pregnancy) miscarriage is an issue in the embryo, not the parents. In a first trimester loss, 60-80% will have a genetic condition called a chromosome imbalance within the embryo that explains why the pregnancy stopped growing. This genetic abnormality is unique to each pregnancy and is a natural part of reproduction.
Why do genetic mistakes happen?
Both egg and sperm can make a mistake with preparing for fertilization, but the culprit is usually the egg, for reasons you’ll soon understand. Eggs are formed when women are still fetuses inside their mothers’ wombs, and the eggs are frozen in genetic suspension for years until ovulation occurs. Sperm, on the other hand, is made and ready to go every single day (millions of them!). When an egg gets ready to ovulate the genetic steps start up again as it becomes prepared for fertilization. Mistakes happen with sperm as well, but sperm are not sitting around for years waiting for this developmental change. Eggs are in limbo for years until ovulation and it isn’t until the time of ovulation that the real genetic work must happen.
Understanding this fundamental difference between male versus female biology explains why the fertility window is so different for men and women. It is not a women’s fault that eggs usually make the genetic mistake, it’s biology and the way we were built. No cells in our body work as well at age 40 as they did at age 20!
This does not mean all the eggs are bad at any given age, but it can explain why it takes longer to conceive, fertility treatment success rates are lower, and miscarriage rates increase as women age.
I want my patients to have a realistic understanding about their chances of another miscarriage, but I have many reasons to leave them feeling encouraged and positive about their journey. I want my patients to leave my office feeling educated, empowered, and encouraged to try to conceive again, either naturally or with treatment. It’s all about changing the mindset from feeling broken to feeling confident and cared for moving forward.
If you are curious about your fertility or have been trying to conceive without success, we are here for you!
About The Author
Dana Ramsey is a Certified Nurse Midwife and has spent the past 15 years helping women navigate their gynecology, pregnancy, postpartum, and menopausal challenges. Dana is dedicated to helping her patients overcome conditions impacting their ability to conceive and maintain a successful pregnancy.
