What counts as infertility, and how common is it?

What the word means

The World Health Organization (WHO) describes infertility as a condition of the male or female reproductive system. It is defined as not becoming pregnant after 12 months or more of regular sex without contraception.

"Regular sex" usually means every two to three days through the cycle. It does not mean sex only on certain days.

The word can sound harsh and final. In medicine it simply describes a situation where conceiving is taking longer than expected, so that it makes sense to look for reasons. Many people who meet this definition go on to have a pregnancy, some with treatment and some without.

Good to know. Infertility is a description of what has happened so far, not a prediction. It does not mean you can never have a child.

Primary and secondary infertility

Doctors sometimes add one of two words:

Term	What it means
Primary infertility	A pregnancy has never happened
Secondary infertility	There has been at least one pregnancy before, but a new one is not happening

Secondary infertility is common, and it is often overlooked. People who already have a child may hear "it happened once, it will happen again", and feel they cannot ask for help. Earlier pregnancies are useful information for a doctor, but things can change over time. Age, a new health condition, surgery, an infection, or changes for the male partner can all play a part. It is just as reasonable to seek an evaluation the second time.

A previous pregnancy that did not continue also counts as a pregnancy here. It is worth telling your doctor about it.

How common it is

In 2023 the WHO estimated that about 1 in 6 people worldwide experience infertility at some point in their lives. The figure was broadly similar across high-, middle- and low-income countries.

So if you are finding it hard to conceive, you are far from alone, even if nobody around you talks about it. In India, difficulty conceiving is often kept private because of family expectations and stigma. That silence can make it feel rarer than it really is.

It involves both partners

A common belief, in India and elsewhere, is that difficulty conceiving is a woman's problem. That is not what the evidence shows.

• Causes can lie with the person who would carry a pregnancy, with the male partner, or with both.
• In many couples, more than one factor is found.
• In some couples, the usual tests are normal and no clear cause is found. This is called unexplained infertility.

Because of this, guidelines suggest that both partners are assessed from the start. For a male partner, a semen analysis is a simple, non-invasive first test. Testing both partners early can save months of tests and worry for one person alone.

Common reasons doctors look for

A first evaluation usually checks a few key steps in conception:

• Ovulation: whether an egg is being released regularly. Irregular or absent periods can be a sign it is not.
• Tubes and uterus: whether the fallopian tubes are open, and whether the uterus has anything that could affect implantation, such as fibroids or polyps.
• Sperm: the number, movement and shape of sperm.
• Age and egg reserve: fertility gradually changes with age, especially for the person with ovaries.

Conditions such as polycystic ovary syndrome (PCOS), endometriosis, thyroid problems and past pelvic infections can affect these steps.

Single people and same-sex couples

The WHO definition is written around couples having sex. If you are single or in a same-sex relationship, the questions are a little different: you may want to understand your own fertility, or plan treatment with donor sperm. A doctor can explain which tests and options apply to you.

It is not anyone's fault

Infertility is a medical condition. It is not caused by something you did wrong, by "thinking too much", or by being "too stressed". Blame, from yourself or from others, does not help anyone conceive.

Caution. Be wary of anyone who promises a quick fix or a certain result. Reliable care starts with understanding the cause, and no honest doctor can promise an outcome.

If this is weighing on you, support is available. Tele-MANAS offers free mental-health support 24x7: call 14416 or 1-800-891-4416.

When to see a doctor

• You are under 35 and have been trying for 12 months.
• You are 35 to 39 and have been trying for 6 months.
• You are 40 or over and want to try, or have just started.
• At any age, if periods are very irregular or have stopped, you have known endometriosis or a past pelvic infection, you have had two or more pregnancy losses, or there is a known concern for the male partner.

Our guide on when to see a fertility doctor explains these timings in more detail. Our specialist checker can help you think about who to see first. Severe pelvic pain, heavy bleeding or fainting needs urgent care: call 112 or go to the nearest hospital.