The NHS advises seeing a GP if you haven't conceived after a year of regular, unprotected sex. If you're 36 or over, NICE guidance recommends seeing a GP after six months instead. However, this is a guide to when you should seek help, not a verdict on your body.
Infertility is more common than most people realise. Around 1 in 7 UK couples have difficulty conceiving, and more than 8 out of 10 couples, where the woman is under 40, will conceive naturally within a year of trying. So if you're only a few months in, it doesn't automatically mean something is wrong. Think of this as a starting point for understanding your body, not a diagnosis.¹
There's no single symptom that confirms infertility, but certain patterns are worth paying attention to, especially if you notice more than one at the same time. These are some of the most recognised signs of female infertility:
A typical menstrual cycle runs around 28 days, but anywhere from 21 to 35 days is considered normal. Your periods count as irregular if the gap between them is shorter than 21 days, longer than 35 days, or changes unpredictably each month. Irregular cycles often point to a problem with ovulation, which makes it harder to know when, or whether, you're releasing an egg each month.
Some period pain is normal, but some signs are worth flagging to a GP. These include periods that stop you doing your usual activities, heavy bleeding that means changing your pad or tampon every 1 to 2 hours, needing to use two products at once, or soaking through your clothes. Both very painful and very heavy periods can be linked to conditions like endometriosis or fibroids, which can also affect fertility.⁶
Ovulation usually comes with subtle signals, like a change in cervical mucus around the middle of your cycle. If you never notice these changes, or your cycle doesn't seem to follow any pattern, it may be a sign you're not ovulating regularly. This isn't something you can confirm on your own – it's one of the things a GP can test for.
Acne, excess hair growth on your face or body, thinning hair on your scalp, or weight gain that's hard to explain can all be signs of a hormonal imbalance. These symptoms are closely associated with polyendocrine metabolic ovarian syndrome (PMOS), previously known as polycystic ovary syndrome (PCOS), one of the hormonal conditions linked to fertility problems in women.³
Pain in your lower stomach or pelvis that shows up outside of your period is worth mentioning to a GP. It's not something to self-diagnose, but persistent pelvic discomfort shouldn't be brushed off either.
Understanding the causes of infertility in women can help make sense of what you're noticing. Here are the most commonly recognised ones:
Problems with ovulation are one of the most common causes of infertility in women. This includes PMOS, thyroid problems (both overactive and underactive), and premature ovarian failure, where the ovaries can stop working before the age of 40.²
Fibroids, endometriosis, and blocked or damaged fallopian tubes can all make it harder to conceive. Fibroids are non-cancerous growths in or around the womb. Fallopian tube damage often comes from previous pelvic surgery or a pelvic infection.²
Fertility naturally declines with age. This is simply biology, not a reflection of anything you've done. It's one of the reasons the NHS and NICE recommend women aged 36 and over see a GP sooner, after six months of trying, rather than waiting the full year.
Being significantly overweight or underweight can affect ovulation. Smoking, including passive smoking, can make it harder to conceive. And untreated sexually transmitted infections, including chlamydia, can damage the fallopian tubes and affect fertility.
Many women with fertility problems have no obvious signs at all, and in around a quarter of cases, no cause is ever identified in either partner. Equally, having one or two of the signs above doesn't mean you're infertile.
The only reliable way to know how to tell if you're infertile is through your GP. They can take a full history, run tests, and refer you to a fertility specialist if needed. Self-diagnosing from a symptom list will only add to your worry, and it isn't something search results can substitute for.
Signs of infertility in a teenage girl look a little different, and they're worth taking seriously without jumping to conclusions. Periods usually start around age 12, though this varies. The NHS recommends seeing a GP if periods haven't started by age 15, or by 13 if there are no other signs of puberty, such as breast development.⁷
Beyond delayed periods, extremely irregular cycles, or periods so painful they interfere with school or daily life, are also worth discussing with a GP. These signs don't automatically mean a lifelong fertility problem. Often they're linked to something manageable, like a hormonal imbalance, but getting it checked early means any underlying cause can be picked up sooner rather than later.
Wherever you are in working out what's going on with your body, you don't have to navigate it alone or wait until every question is answered before taking a step forward. twoplus was built for couples trying to conceive who want a way to try at home, in their own time and their own space.
The twoplus Applicator Extra is an at-home insemination device, classified as intracervical insemination (ICI). It's designed to deposit sperm close to the cervix, giving couples a comfortable, private option to try alongside everything else they're learning about their fertility. It isn't a replacement for medical treatment or GP advice, and it isn't a fix for an underlying condition like PMOS or endometriosis, but for couples without a diagnosed barrier to conception, or who are exploring their options before or alongside seeing a specialist, it can be a supportive, low-pressure step to try.
Alongside the Applicator Extra, twoplus also offers ovulation test kits, which can help you build a clearer picture of your cycle and when you're likely to be fertile, and fertility supplements for both partners. Used together, these tools can help you feel more informed and more in control while you figure out your next move.
The earliest signs are usually cycle-related, things like irregular, absent, or unusually painful periods, but many women notice no signs at all before struggling to conceive.
Yes. Regular periods suggest you're likely ovulating, but they don't rule out other causes, such as blocked fallopian tubes, endometriosis, or unexplained infertility, which accounts for around 1 in 4 cases.²
The NHS recommends seeing a GP after 12 months of trying, and NICE guidance says after 6 months if you're 36 or over. See a GP sooner if you notice irregular periods, very painful periods, or other symptoms covered above.¹,⁸
Sometimes. Maintaining a healthy weight, cutting back on smoking and alcohol, and managing stress can all support more regular cycles, but if irregular periods are linked to a condition like PMOS or a thyroid problem, lifestyle changes alone usually aren't enough, and it's worth speaking to a GP.
NHS – Infertility (overview): https://www.nhs.uk/conditions/infertility/
NHS – Causes of infertility: https://www.nhs.uk/conditions/infertility/causes/
NHS – Polyendocrine metabolic ovarian syndrome (PMOS): https://www.nhs.uk/conditions/polyendocrine-metabolic-ovarian-syndrome-pmos/
NHS – Irregular periods: https://www.nhs.uk/symptoms/irregular-periods/
NHS – Heavy periods: https://www.nhs.uk/conditions/heavy-periods/
NHS – Endometriosis: https://www.nhs.uk/conditions/endometriosis/
NHS – Starting your periods: https://www.nhs.uk/conditions/periods/starting-periods/
NICE – Fertility problems: assessment and treatment (NG257): https://www.nice.org.uk/guidance/ng257
