Age is the single biggest factor in fertility, and the conversation around it is often more frightening than helpful. Statistics are real, but they describe populations, not individuals. Here are the facts, without the pressure.
The Biological Timeline
- Late teens to late 20s: Peak fertility. Highest egg quantity and quality.
- Early 30s: Gradual decline begins. Many people conceive easily in their early 30s.
- After 35: Decline accelerates somewhat. More time may be needed to conceive. The recommendation to see a doctor earlier (after 6 months vs 12) reflects this.
- After 37-38: More noticeable decrease in egg quantity and quality.
- After 40: Conception is still possible naturally, but takes longer on average and miscarriage rates are higher.
- After 45: Natural conception is rare but does happen.
What Actually Changes
- Egg quantity: You are born with all the eggs you will ever have. This supply decreases over time through a natural process of attrition.
- Egg quality: Older eggs are more likely to have chromosomal abnormalities, which increases the risk of miscarriage and conditions like Down syndrome.
- Cycle changes: Cycles may shorten or become less predictable as ovarian reserve declines.
- Hormonal shifts: FSH (follicle-stimulating hormone) rises and AMH (anti-Mullerian hormone) declines as reserves decrease.
Male Age Matters Too
Sperm quality also declines with age, though more gradually than egg quality. Research shows increases in sperm DNA fragmentation and reductions in motility after 40. Read more about male fertility.
What You Can Do
- Track your cycle and understand your patterns. Bloom helps you do this privately and without noise.
- Maintain a healthy lifestyle: balanced nutrition, moderate exercise, avoid smoking and heavy alcohol.
- Start trying sooner rather than later if you know you want children and your circumstances allow.
- Consider fertility testing (AMH, AFC) if you are over 35 and want to understand your current reserves before deciding when to try.
- Egg freezing is a valid option for those who want to preserve fertility options. Consult a reproductive specialist for honest information about success rates by age.
When to Seek Help
- Under 35: After 12 months of trying without success.
- 35-39: After 6 months of trying.
- 40 and over: Consider consulting a specialist before or soon after starting to try. Time is a factor worth taking seriously.
Perspective
Many people conceive naturally after 35 and even after 40. The statistics reflect what happens across large populations; your individual circumstances, health, and timing all matter. A doctor or reproductive specialist can give you a clearer personal picture than population statistics ever can.
Track Your Cycle with Bloom
Understanding your cycle is one of the most empowering things you can do at any age. Bloom is private, ad-free, and built around your wellbeing.
Frequently Asked Questions
Is 35 a fertility cliff?
No. Age 35 is a statistical inflection point, not a cliff. The decline in fertility is gradual and starts in the early 30s. At 35, chances of conceiving naturally per cycle are lower than at 25, but many people conceive naturally in their mid to late 30s.
Can lifestyle choices offset age-related fertility decline?
Lifestyle choices help optimize the fertility you have, but they cannot fully reverse biological changes in egg quantity or quality over time. Not smoking, maintaining a healthy weight, managing stress, and eating well all support fertility at any age.
Should I test my fertility even if I am not trying yet?
If you are curious about your ovarian reserve, tests like AMH (anti-Mullerian hormone) and AFC (antral follicle count) can give useful information. These are not crystal balls, but they can help inform timing decisions. Talk to your doctor about what makes sense for you.