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Not Pregnant Yet?

If you don't get pregnant straight away, it doesn't mean you have a problem. One in two couples could be trying for a baby at the wrong time2. So one of the easiest ways to help increase your chances is to find when you're most fertile.

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What can affect your fertility?

There are three common areas where things can be wrong and make it difficult getting pregnant, but this list is not exclusive and your own individual situation may not fit within one of these categories:

Problems with hormones
  • Anovulation

    Ovulation is controlled by your fertility hormones. So if for any reason your hormone levels are disturbed, your ovulation can be affected. A sign of possible ovulation problems is very irregular or no periods. You may find that you are ovulating, but not every cycle.

    Hormonal disturbance that can affect ovulation can be caused by many factors. These include dramatic changes in weight, stress, strenuous exercise and illness. Occasional cycles without ovulation are common and occur in 2 -12% of cycles in healthy women with regular periods1-5. If you fail to see PEAK on the Clearblue Advanced Fertility Monitor or Clearblue Digital Ovulation Test with Dual Hormone Indicator, or don't detect the LH surge with ovulation tests for 3 consecutive cycles, you should speak to your doctor. This article contains more information about anovulation.

  • Polycystic Ovarian Syndrome (PCOS)

    It is estimated that up to 1 in 10 women have PCOS6. PCOS describes a hormone imbalance that causes a variety of symptoms including irregular periods, excess body hair, oily skin, weight gain, depression and problems trying to conceive. Your doctor will be able to diagnose it with a blood test and possibly an ultrasound scan to look for characteristic cysts on the ovaries. PCOS may cause you not to ovulate. In one study, women who were suspected to be not ovulating, or who had irregular periods were assessed and over 90% (9 in 10) were found to have PCOS7.

    If you would like to read more about PCOS and how it affects fertility, this article might be of interest to you.

  • Short Luteal Phase

    If the number of days between when you ovulate and when your next period starts is too few (less than 10), this can mean that although you may conceive, the fertilised egg is expelled before it can implant in the lining of the womb. This is something you may notice if you are using an ovulation test or fertility monitor — count the number of days between your second peak fertile day and when your period starts. Talk to your doctor about this as the condition may be treatable.

  • Early Menopause

    Once you have reached menopause, pregnancy is not possible, and in the lead up to menopause (the peri-menopause) it can be very difficult to become pregnant. If your mother had an early menopause your chances are much higher, so, try to find out at what age your mother started menopause. If she had an early menopause it may be worth talking to a healthcare professional about your future plans for pregnancy. There are a number of tests which can estimate the number of eggs left in the ovaries to see whether you are approaching the menopause, such as a blood test for the Anti-Mullerian Hormone (AMH) or Follicle Stimulating Hormone (FSH), or an ultrasound scan to check eggs and ovaries.

Problems with Fallopian tubes

A blockage in your Fallopian tubes can prevent sperm getting to the egg. There are medical procedures which might help, so it's worth speaking with a medical professional about this.

  • Untreated chlamydia infection

    The most common cause of blocked Fallopian tubes is a chlamydia infection that has been left untreated. Chlamydia is a common infection that is easily transmitted by unprotected sex. Some women may be completely unaware that they ever had a chlamydia infection due to the lack of symptoms. If there's a chance you could have contracted Chlamydia, go to your doctor for a test.

  • Fibroids

    These are abnormal growths of muscular tissue in the womb that can block the Fallopian tubes or stop a fertilised egg implanting. Typical symptoms include heavy or painful periods. If you want to get pregnant but suspect or know you have fibroids, please visit your doctor for further advice.

  • Endometriosis

    This is when the tissue that lines the womb grows outside the womb. It can obstruct the Fallopian tubes and can prevent fertilisation. Endometriosis can cause heavy and/or very painful periods. It can be treated by medication or by removing the extra tissue. Your doctor will be able to tell you more.

Other considerations

Vaginal dryness is more common than we may think. In a study across 11 countries involving 6,725 women8, up to 18% of women aged 18–34 years reported always or usually experiencing vaginal dryness. This can be exacerbated by the tendency for 'baby-making sex' when trying to conceive. Some of the most commonly available lubricants can be toxic to sperm and even saliva is — so be sure to use a sperm-friendly lubricant.

Unprotected intercourse in the days leading up to and/or on the day of ovulation is needed to become pregnant. This can be achieved by having sex every 2-3 days, but many couples find this impractical. Therefore, making sure you know when you ovulate and having intercourse at this time will maximise your chances of a natural conception. A recent study5, amongst women trying to conceive, found that women using a digital ovulation test were 77% more likely to fall pregnant than those simply having regular intercourse.

What can lower fertility?3

  • Drinking alcohol

    Fertility in both men and women can be affected by drinking too much alcohol. Clinical guidelines in the UK advise a maximum of 1-2 units per day for women and 3-4 units per day for men, whether you are trying to conceive or not. Reducing the amount of alcohol you drink can help you to conceive.

  • Smoking

    Compared to non-smokers, men who smoke can have a lower sperm count and/or a higher number of abnormal sperm. In women, smoking can affect fertility and trigger early menopause. It can also increase the risk of miscarriage and early onset of labour. Smoking is very bad for the health of your unborn baby and it is best to stop smoking before you become pregnant.

    Both you and your partner should try to stop smoking if you're trying to conceive.

  • Recreational Drugs

    There are many different sorts of recreational/illegal drugs used today and how they affect fertility is not well studied. As many drugs can have bad effects on a developing baby, you should stop using any recreational/illegal drugs when trying to conceive.

  • Weight

    Being underweight or overweight can alter your menstrual cycle and reduce your chances of conception. Overweight men can have a lower sperm count and poor sperm quality. Visit your doctor or nurse to know the ideal weight for you and for practical advice on gaining or losing weight if it's necessary.

  • Medication

    If you, or your partner, are taking any medication, check with your doctor that it won't reduce your fertility. There may be alternatives available.

  • Age

    You are born with a lifetime's supply of eggs and the number reduces gradually with age. After 38-40 years the impact of egg loss is much higher (as your reserve is already lower) and the quality of the eggs also declines. If you're over 35, it's a good idea to visit your doctor after around six months of trying and if you're over 40, ask your doctor for advice when you start trying to conceive. Less is known about fertility in older men but it's thought to decline from around the age of 40 too.

Unexplained infertility

Sometimes all clinical tests will be reported as normal, but after years of trying, you're not pregnant. This can be very frustrating and distressing because there is nothing to focus on that can be rectified or treated. It is estimated that around one third of couples with unexplained infertility will get pregnant naturally within three years without intervention6.

What is sub-fertility and infertility?

The majority of couples who have tried to conceive for over two years without success are technically 'sub-fertile'. Although ovulation and sperm production may occur they can have difficulty conceiving due to issues with hormones or physical difficulties in the reproductive tract. Many fertility problems can be treated, so if you're worried, visit your doctor. Complete infertility – where the woman doesn't ovulate at all or the man's ejaculate doesn't contain sperm - has been shown in a study to occur in approximately 9% of the population9.

Fertility issues are due to a female related problem in approximately one third of cases, one third are due to a male related problem and in one third of cases are due to an issue of compatibility or a combined problem10. If you have been trying for a baby for a year with no success and are under 35, we recommend that you speak to your healthcare professional for further advice. If you are aged over 35, you should seek help after 6 months trying, and immediately if you are over 40.

  1. Hambridge H.L., et al. The influence of sporadic anovulation on hormone levels in ovulatory cycles. Human Reproduction (2013) 28 1687–94
  2. Haiman C.A., et al. Ethnic differences in ovulatory function in nulliparous women. British Journal of Cancer (2002) 86 367–71.
  3. Johnson S. Incidence and description of endocrine abnormalities in menstrual cycles from women with no reported infertility. British Fertility Society, Sheffield, UK Jan 8-9, 2014
  4. Park S.J. et al. Characteristics of the urinary luteinising hormone surge in young ovulatory women. Fertil. Steril. (2007) 88 684-90
  5. Wilcox A.J. et al. Timing of sexual intercourse in relation to ovulation. N Engl J Med (1995) 333:1517-1521
  6. The Thessaloniki ESHRE/ASRM-Sponsored PCOS Consensus Workshop Group. Consensus on infertility treatment related to polycystic ovary syndrome. Human Reproduction (2008) 23(3): 462-477
  7. Broekmans, F. J., et al. PCOS according to the Rotterdam consensus criteria: change in prevalence among WHO‐II anovulation and association with metabolic factors. BJOG (2006) 113 (10): 1210-17.
  8. Leiblum SR, et al. Vaginal dryness: a comparison of prevalence and interventions in 11 countries. J Sex Med. (2009) 6: 2425–2433. - See more at:
  9. Tiplady S., et al. Digital Ovulation Tests do not Affect Levels of Stress in Women Trying to Conceive. Human Reproduction (2013) 28(1): 138-151
  10. NICE Clinical Guideline 62 (2008)
  11. Boivin J., et al. International estimates of infertility prevalence and treatment-seeking: potential need and demand for infertility medical care Human Reproduction (2007) 22: 1506-12 4

For information purposes only. Consult a doctor for medical advice.

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Clearblue Advanced Fertility Monitor

Proven to increase the chances of getting pregnant naturally by 89%1

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1In the first 2 cycles of use. Robinson, JE, Fertility & sterility (2007) 87:329-334.

Did you know?

Ask the Clearblue expert


How do I calculate the length of my menstrual cycle?


To work out your cycle length, count the day your period starts (first day of full menstrual flow) as Day 1, and continue counting through to the day before your next period starts. The number of days is your cycle length.

Clearblue Ovulation Tests help you get pregnant naturally

Learn more

Clearblue Advanced Fertility Monitor

Proven to increase the chances of getting pregnant naturally by 89%1

Buy now

1In the first 2 cycles of use. Robinson, JE, Fertility (2007) 87:329-334.

Did you know?

A healthy lifestyle may help you conceive. Being either overweight or underweight may cause difficulties when getting pregnant.

Learn more

Maximise your chances of pregnancy

Clearblue Digital Ovulation Test with Dual Hormone Indicator helps you pinpoint your most fertile days.

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Did you know?

Your partner's testes are at their best when they are relatively cool. So wearing loose underwear and light trousers and avoiding hot baths can help improve his sperm production.

Ask a Clearblue expert:


My cycles never seem to be the same length, is that normal?


Many women quite naturally have a menstrual cycle that varies by a few days month to month. If you are trying for a baby, accurately identifying your wider fertility window can be an advantage. A fertility monitor will tell you the days of high fertility and peak fertility with a wider window of opportunity during which there's a chance to conceive.

Clearblue Advanced Fertility Monitor

Proven to increase the chances of getting pregnant naturally by 89%1

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*In the first 2 cycles of use. Robinson JE, et al. Fertility & sterility (2007) 87: 329-334.


Do I need to wait several days after I have missed a period before doing a Clearblue Pregnancy Test?


No. All Clearblue Pregnancy Tests are sensitive enough to detect hCG in your urine from the day your period is due. You can use Clearblue Pregnancy Tests up to 4 days before your period is due, although the pregnancy hormone levels in your urine may not be high enough to be detected. So if you test early and you get a "Not Pregnant" test result, it's recommended that you test again when your period is due. All Clearblue Pregnancy Tests are over 99% accurate, when testing from the day the period is due.

Clearblue Digital Pregnancy Test with Weeks Indicator is the only pregnancy test that tells you how many weeks

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