Having a baby after 35: does fertility really "fall off a cliff?"
Updated: May 12
We so often hear the idiom that “fertility drops off a cliff” at age 35. It sounds pretty scary if you're approaching that birthday without yet having had kids. But is it actually true?!
The simple answer is: no, not really.
While it’s true that fertility naturally declines as you get older, it’s less of a cliff and more of a... slope. Throughout your twenties and early thirties your fertility is constantly falling, but gradually.
Between 30 and 33 years old there is actually no real difference in your chances of conceiving each month of trying. Between 34-39 the likelihood gradually falls until, when you’re over forty, you have less than half the chance of conceiving as a 30 year old.
With that said, at 35, it does start to fall more rapidly. So what does this mean in real terms? The best data we have indicates that:
In your 20s...
you have around a 25% chance of conceiving naturally each month, assuming you are generally healthy and have sex on a fertile day.
In your early 30s...
that reduces to about a 20% chance per month.
Around age 35...
You're looking at a 15% chance.
Beyond age 40...
you can expect about a seven percent chance per month of actively trying.
By the time you’re over 45...
your chances of getting pregnant during each menstrual cycle are considered less than 1%, around which time you will likely be transitioning into menopause.
So, while there is not really any such thing as a “fertility cliff,” or one age where it suddenly drops off, it’s important to be aware of the real likelihood that it will be both harder to get pregnant and harder to stay pregnant. That’s why it can take a number of months, maybe even a year or two, to conceive. And, even then, this only accounts for the ability to get pregnant, it doesn’t mean that the pregnancy will lead to a healthy baby. Your odds of miscarriage increase with age as well.
So, as you can see on the chart below, in your early 30’s, you have about 20% chance of miscarriage but by the time you hit your early 40’s, roughly half of pregnancies can end in miscarriage.
Of course, this only tells half the story.
The other crucial component is, of course, sperm. Here’s a bit of food for thought: infertility is commonly billed as a women’s health issue, but, in fact, 43% of infertility cases are also attributed to the male partner. Men’s fertility does also decline with age, just not as predictably or demonstrably as women’s. Sperm freezing is rightfully getting more popular too!
Despite the fact the "cliff" doesn't exist, if you are approaching 35, or you're older, and you haven't yet started a family, it's a great idea to get a consultation with a fertility doctor, who can run some tests and make sure you're working with the real facts, not fears.
Get the full story in Everything Egg Freezing, the Step-by-Step Guide to Doing it Right.