When It Comes To Fertility, Is Age The End All Be All? The New Science Behind Biological vs Chronological Age
We think of age as the number one cause for infertility. Is this true?
Just this week a study published in the Journal of the American Medical Association (JAMA) investigating 60-year trends in age of menopause and reproduction among US women found an increase in the length of our reproductive life span.
How can that be?
While as women we do have limited numbers of eggs and time ovulating, we can have better quality eggs by taking care of our health even as we age. The same is true for your guy. His sperm can be better quality even as he ages.
How? Functional Medicine, personalized nutrition, and taking extra special care of your body.
Chronological vs. Biological Age
Chronological age: The amount of time you have been alive. The number on your driver's license.
Biological Age: The age at which your body functions. You can be 35 but have a biological age of 25.
We all know someone who looks awesome for their age. Gwynweth Paltrow or Tom Brady come to mind. Many of us chalk it up to good genes (and lots of extra help that comes with having lots of money). In fact, both of them are famous for prioritizing healthy nutrition and lifestyle for optimal health and longevity—and you can see the results.
Genes play a role, but they are not the end all be all. Remember, even with “good genes” you can live an unhealthy lifestyle and not manifest your genetic potential. Or you could have a number of genetic risk factors for disease, but be doing fabulously because you focus on managing your risk and taking care of your body.
There is an emerging field of science trying to track biological age. There are a few telltale biomarkers that can be drawn from a blood sample or saliva.
DNA Methylation is one area scientists are reviewing to look for biological age. DNA methylation is essential for embryonic development, genomic imprinting and chromosome stability, all of which influence age. Studies show that different body tissue parts can have different “ages” based on DNA methylation.
Other more standard labs such as homocysteine, HbA1c, CRP, cholesterol, and alkaline phosphatase measure when you have pre-disease markers, which can be a sign of advanced aging. A number of my clients, even in their 20s, have blood markers that are “high normal” or “abnormal.” This signifies risk for accelerated aging, future disease, and potentially reduced fertility.
Often we can nip this in the bud with nutrition and lifestyle changes.
So does age affect our ability to get pregnant?
Yes, the science shows that age matters in fertility. When you’re younger, you’re simply more fertile. You have more eggs and the eggs are more likely to be chromosomally normal because of less “wear and tear” on your body. Same goes for men and their sperm count and quality.
So it certainly helps to have time on your side. However, it also helps to be ready for a baby. Everything doesn’t need to be perfect, having a child will be your most life changing event. It helps if you’re in the right relationship, and in a place emotionally and financially where you feel ready.
This is why considering biological age and taking care of ourselves to reduce the aging process provides hope and help! The JAMA research on 60 year trends showed between that the fertile window is longer since women are menstruating earlier and entering menopause later. The researchers concluded the women's average reproductive life span was extended by 2.1 years, from 35 to 37.1 total years.
If age is so important, why are people getting pregnant later?
We’re getting married and trying later. In the US, the average age of first time mothers was 26 in 2018 which is up from 21 in 1972. Men went from being first time dad’s at 27 in in 1972 to 31 today.
Especially in urban areas, women are spending longer in school and taking longer to settle, find a job and get married. Washington, DC is a city where people are the oldest in the country when they get married in their ripe mid-30s. It’s fun to look at the differences in cities across the country.
The concerns about money and job security is real. A 2018 Princeton study found that women make less after having a baby, but men don’t. I get frustrated when I hear the statement “women just wait too long and that’s why they're stuck with infertility” as if we’re penalized for safeguarding our future.
At what age does fertility decline?
Age affects our ability to get pregnant because women have a finite number of eggs in their body. We are most fertile in our 20s. The number and quality of our eggs slowly declines in our 30s and more rapidly in our 40s.
At OB-GYN and IVF clinics, 35 is considered the magic number when your fertility falls off a cliff. You go from “needing birth control,” to “never getting pregnant to “being high risk” because of your age. But I would say fertility declines more significantly at age 40.
I’ll never forget when I was leaving the hospital after having my daughter I received a giant packet of health records marked “HIGH RISK.” On closer inspection I found the notation, “Over the age of 35.” I had experienced a healthy pregnancy, an uncomplicated,full-term labor and gave birth to a beautiful healthy girl. I was completely successful—yet I was marked “HIGH RISK.”
Over the age of 40 we do see reduced fertility and an increased risk in miscarriages due to chromosomally abnormal eggs. But reduced fertility is not as significant when you look at averages as many are led to believe. You can get pregnant after 40 and have a healthy baby, despite the odds.
What age does a woman stop being fertile? What age is it too late to have a baby?
A woman’s fertility declines in her 40s and she stops being fertile once she has completed menopause. After menopause, a woman no longer produces eggs and thus cannot become pregnant naturally (although it is possible with a donor egg). The age in which women go through menopause varies based on a variety of factors including family history. Older data show women stop being fully fertile about 5-10 years before completing menopause. We don’t have good data on reversing biological aging and how this can contribute to improving fertility as women get closer to menopause.
To have the best odds, you want to try to get pregnant when you have more eggs. The closer you are to menopause, the harder it is to not only get pregnant, but stay pregnant.
The closer you are to menopause, the more miscarriage risk goes up along with the difficulty in getting pregnant. There are also health risks associated with women who are of advanced age due to genetic disorders or chromosomally abnormal eggs such as down syndrome.
That said, it’s possible to have a healthy baby into your 40s, but with more effort required to counteract the aging process. This involves significant lifestyle change in what you eat, how you exercise, sleep, live and your work/home environment.
There is more risk and having close supervision of an OBpGYN or midwife is important. Donor eggs can be used late into your 40s and this is often how older Hollywood celebrities are having babies.
How can I boost my fertility?
Improve your egg quality.
Eating a healthy diet and exercising moderately (not overtraining, but focusing on health and fitness) are two basics, but you can take it so much further to help with your fertility.
You can boost your fertility by focusing on functional medicine and personalized nutrition for anti-aging benefits to improve your egg quality and your partner’s sperm quality.
Precisely what does this mean?
Figure out your genetic risks and underlying health conditions and address them.
Treat your body like an athlete (minus the uber intensive workouts) with targeted nutrition, exercise that matches your needs and body type, sleep improvements, and changes to what you use on your body and in your house. Personal care and home care products should be nontoxic and green—not harmful to your reproductive health.
Can you improve egg quality over 40?
Absolutely! You can improve egg quality at any time. It‘s just that you have fewer and fewer eggs available so it’s a game of odds. You can have better eggs over 40 with significant lifestyle change, but you don’t have as much time to make those changes and you have fewer eggs to work with.
Learn more about The Importance of Egg Quality.
Functional medicine for improving fertility and egg quality
At Simplina, we figure out what you need and take a blend of functional medicine, functional nutrition, and personalized medicine to custom create an ideal blueprint to optimize your health.
There are some really exciting developments in nutrition and the science of fertility that I use in my practice like the supplements NAD+, ubiquinol that have been shown to improve egg quality and fertility when taken at the right dose, using the right product, and at the right time.
We take a functional medicine look at your hormones, your gut health and ability to digest, and your nutritional status to identify “weak points” in your body and what needs to be changed, tuned up, or better supported.
We look for and address systemic inflammation and risk factors for auto-immunity. The healthier you are. the better chance you have to prevent accelerated biological aging.
We utilize functional nutrition to identify good quality food to match your specific needs, guide your eating in a rhythm that supports your body, and control your blood sugar, adding supplements targeted for you.
We layer your custom nutritional plan on top of support for your mind, body, and stress-relief and explore how your environment (i.e. your home life, personal care, and cleaning products, etc.) supports or hinders your ability to be as healthy as possible.
What can I do to increase my chances of getting pregnant?
To increase your chances of getting pregnant, start taking care of yourself —today!
Eating real food, including 5-9 servings of fruits and veggies daily (using organic food especially meat/dairy when possible), can clean-up your diet on a basic level surprisingly quickly. Exercising daily with low to moderate intensity exercise along with drinking half your bodyweight in water is another good first step.
This information on age and fertility absolutely provides hope that 35 isn’t the end all. Science shows you can do things to reduce how quickly your body ages and increase your fertility.
Get my free fertility guide on my homepage that gives you a few more pointers. But it’s really best to get a fertility plan personalized for you. Book the fertility care package and we can get started today.
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Annina is a PhD, Registered Dietitian, Licensed Dietitian Nutritionist and Board Certified in Functional Medicine specializing in nutrition and functional medicine for fertility, pregnancy and new mom and baby. She has 7 years of practice experience and has co-authored several books on infant, child nutrition and obesity prevention.