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Chances of Getting Pregnant

Enter your age to see the average chance of conceiving in a single cycle, and how that adds up over 6 and 12 months of trying. These are population averages for healthy couples — a helpful frame of reference, not a personal prediction.

Enter your age to see the average chance of conceiving each cycle, and cumulatively over 6 and 12 months.

How conception chances add up

In any single cycle, even for a young, healthy couple with perfect timing, the chance of conceiving is only around 1 in 4. That can feel low — but because you get a fresh chance each cycle, the odds compound over time. A 25% monthly chance becomes about an 82% chance within six cycles and over 95% within a year. This calculator works out that cumulative picture for your age, so a few months without success can be seen for what it usually is: completely normal, not a red flag.

Age and the per-cycle chance

The strongest single factor in these averages is age, because both egg quantity and quality decline over time — gradually at first, then more noticeably from the mid-30s. As a rough guide to the average per-cycle chance for a healthy couple:

  • Early-to-mid 20s: around 25% per cycle
  • Late 20s: about 20%
  • 30 to 34: roughly 15–18%
  • 35 to 37: about 12%
  • 38 to 40: around 8%
  • 41 and over: about 5% or less

It’s a slope, not a cliff — plenty of people conceive naturally in their late 30s and 40s. But the averages explain why the “when to seek help” timeline shortens with age.

Making the most of each cycle

Whatever your age, the single biggest thing within your control is timing: conception is only possible in the fertile window — the five days before ovulation plus ovulation day itself. Having sex during those days, or simply every 2–3 days across the cycle, gives each cycle its best shot. Our fertile window calculator and signs of ovulation guide help you pinpoint the right days, and the how to get pregnant guide covers the rest.

A note on averages

Please hold these numbers loosely. They’re population averages, and any individual couple can be well above or below them for reasons a calculator can’t see — cycle regularity, health conditions, sperm factors, and plain chance all play a part. Use this as reassurance and a rough timeline, not a verdict, and if you’re worried or you’ve passed the “seek advice” mark for your age, a provider can check things properly.

Frequently asked questions

What are the chances of getting pregnant each month?
For a healthy couple having regular unprotected sex, the average chance per cycle is roughly 25% in the early 20s, around 20% in the late 20s, about 15% at 30–34, and lower from the mid-30s on (closer to 10% at 35–37 and 5% or less past 40). These are averages — your own odds depend on many personal factors, and timing sex to your fertile window improves your chances each cycle.
How many couples conceive within a year?
Most do. About 8 in 10 couples under 35 conceive within a year of trying with regular unprotected sex, and most of the rest within a second year. The figure is lower and the timeline longer with age. That's why 'when to seek help' guidance is 12 months under 35, but 6 months at 35–39, when it's worth getting checked sooner.
How does age affect fertility?
Fertility gradually declines with age, especially from the mid-30s, because both the number and quality of eggs decrease. It's a gradual slope, not a cliff — many people conceive naturally in their late 30s and early 40s — but the average chance per cycle falls and the chance of miscarriage rises with age. Age affects egg-bearing partners more than sperm-bearing ones, though sperm quality declines slowly too.
When should we see a doctor about not conceiving?
The usual advice is to see a provider after 12 months of regular unprotected sex if you're under 35, or after 6 months if you're 35 or older, because investigating sooner matters more with age. See someone straight away — without waiting — if you have irregular or absent periods, known reproductive conditions (like PCOS or endometriosis), previous pelvic surgery, or other reasons to suspect a problem.
How can we improve our chances each cycle?
The biggest lever is timing: have sex in the few days before and including ovulation, your fertile window. Beyond that, regular sex (every 2–3 days) across the cycle covers the window even if your dates are uncertain, and general health helps — a balanced diet, a healthy weight, not smoking, limiting alcohol, and a daily folic-acid supplement when trying. Our fertile window and ovulation tools help you find the right days.

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— The Period Tools Team