Chances of Getting Pregnant Within One Year by Age

When you’re trying to conceive (TTC), it can be easy to assume that having sex around ovulation should result in pregnancy straight away. In reality, even when everything is working normally, conception is never guaranteed in a single menstrual cycle.

The updated NICE fertility guideline NG257, published in March 2026, provides particularly useful UK data.

Assuming intercourse approximately twice per week, the cumulative chance of achieving a clinical pregnancy is: 

Age	Pregnant within 12 cycles	Pregnant within 24 cycles
19–26	92%	98%
27–29	87%	95%
30–34	86%	94%
35–39	82%	90%

Overall, NICE advises that more than 80% of heterosexual couples will conceive within one year where the woman is under 40, contraception is not being used and regular vaginal intercourse is occurring. Of those who do not conceive during the first year, approximately half will conceive during the second year. 

Why Doesn’t Pregnancy Happen Every Month?

Human reproduction is surprisingly inefficient.

Even correctly timed intercourse does not guarantee that an egg will be fertilised and develop into an ongoing pregnancy. This means several unsuccessful cycles can occur purely through probability.

Your chance in one cycle and your cumulative chance over multiple cycles are also different concepts.

Think of it this way: repeatedly having a chance of pregnancy each month means your overall probability of having conceived increases as more cycles pass.

That’s why the majority of couples who conceive naturally do so within the first year, despite pregnancy being far from guaranteed during any individual cycle.

When Are You Most Likely to Get Pregnant?

The fertile window is generally considered the six-day period ending on the day of ovulation.

However, not every day carries the same probability.

Evidence reviewed by ASRM suggests that the probability of conception is highest when intercourse occurs during the two days before ovulation, with particularly high fertility around the day before ovulation. 

This is partly because sperm can already be present within the reproductive tract when ovulation occurs.

Trying to identify the exact hour of ovulation is therefore unnecessary for most couples.

How Often Should You Have Sex When Trying to Conceive?

You don’t necessarily need to have sex every day.

The NICE pregnancy statistics above are based on intercourse occurring approximately twice per week, while timing intercourse around the fertile window can help ensure sperm are present when ovulation occurs. 

For many couples, having regular intercourse throughout the cycle is a simpler and less stressful approach than attempting to perfectly predict ovulation.

How Does Age Affect Your Chances of Pregnancy?

Age is one of the strongest predictors of fertility.

Female fertility gradually declines with age, with the decline becoming increasingly important through the later reproductive years. ASRM notes that relative fertility at age 40 is approximately half that of women in their late 20s and early 30s. 

Age is associated not only with a reduced probability of conception but also with increasing rates of chromosomal abnormalities and miscarriage. 

However, population statistics should not be interpreted as an individual’s exact probability of pregnancy. Fertility varies considerably between people of the same age.

Supporting Your Body While Trying to Conceive

CORE3 is Ovare’s doctor-formulated, one-capsule-a-day preconception supplement, created around three nutrients commonly discussed in fertility and preconception research: 450mg CoQ10 (ubiquinone), 1,000µg methylfolate and 4,000IU vitamin D3. Made in the UK, third-party tested, vegan and halal, CORE3 was designed to provide meaningful doses in a simple formulation — without building an expensive daily supplement stack.

What Can Affect Your Chances of Getting Pregnant?

Your chances of conceiving naturally can be influenced by many factors, including:

• age
• whether and how regularly you ovulate
• sperm quality and quantity
• fallopian tube health
• endometriosis
• PCOS and other ovulatory disorders
• frequency and timing of intercourse
• previous pelvic infection or surgery
• smoking and other lifestyle factors
• underlying reproductive or medical conditions

When Should You See a Doctor About Fertility in the UK?

The 2026 NICE fertility guideline states that if pregnancy has not occurred after one year of regular unprotected vaginal intercourse, both partners should generally be offered further clinical assessment and investigation when there is no already-known cause of infertility. 

However, you shouldn’t necessarily wait a year if there is already a reason to be concerned.

Updated NICE quality standards state that people with a known or suspected clinical cause of infertility or a history of factors that predispose to infertility should be considered for earlier referral. Women and others with female reproductive organs aged 36 or over should also be offered referral at presentation because age can affect fertility. 

Is It Normal to Take Several Months to Get Pregnant?

Yes.

One of the most important things to understand when trying for a baby is that an unsuccessful month does not necessarily represent something going wrong.

According to current NICE guidance, more than 8 in 10 couples where the woman is under 40 will conceive within a year of regular unprotected intercourse, and the cumulative probability continues to increase during the second year.

At the same time, fertility statistics describe populations rather than individuals. If you have irregular or absent periods, a known reproductive condition, previous fertility problems or another reason to suspect reduced fertility, seeking medical advice earlier may be appropriate.

The Bottom Line

Your chance of getting pregnant is not 100% each month — even with perfectly timed intercourse.

For women under 40 without a known fertility problem, however, the cumulative chances are reassuringly high: over 80% of couples conceive within one year, and over 90% will ultimately conceive within two years under the circumstances described by NICE. 

Understanding this can make the TTC process slightly less confusing: one negative pregnancy test tells you what happened that cycle. It does not, by itself, tell you your overall fertility.