How long does it take to get pregnant?

When trying to get pregnant, one of the most common things women want to know is how long it will take. The truth is how quickly you get pregnant will depend on several factors, and it isn’t the same for everyone. The fact is that some women will get pregnant faster than others, however, these differences are perfectly normal and not necessarily anything to worry about.

Here are just some of the factors affecting how long it takes to get pregnant:

Four factors that can affect how quickly you get pregnant

1. Your age 

There are many reasons both women and men choose to have children later on in life, including career, financial and environmental considerations. Couples having children in their 30’s or 40’s is becoming increasingly common. Fertility in a woman declines with age, and this decline speeds up from the age of about 35 (1). This is because the number of eggs a woman produces starts to decrease, as well as the quality of those eggs (2). By the age of 40, conceiving can be difficult and fertility treatment may be required.

2. Your reproductive health

There are many conditions affecting reproductive functioning in women. These include:

• PCOS - a common hormonal condition causing the egg follicles in the ovaries to not develop as they should.
• Blocked fallopian tubes - one of the most common causes of infertility, a blocked fallopian tube hinders the ability of the fertilised egg to travel to the uterus and implant in the lining.
• Endometriosis - where the lining of the womb grows in other places in the body, including the bowel, ovary and fallopian tubes. This can cause scar tissue to form within the pelvis and affect fertility.
• Uterine abnormalities - one of the most common uterine abnormalities is fibroids. These can grow in the uterus, interfering with where the fertilised egg would normally implant.
• Premature Ovarian Insufficiency (POI) - also known as early menopause, affects 1% of women under the age of 40 and can, sadly, occur in women in their 20s too, however, this is rare.
• Previous infection - Previous or untreated STIs can cause fertility issues.

3. Your general health

Having certain medical conditions including thyroid disease, diabetes and asthma can all affect fertility. Taking certain medications can also interfere with reproductive functions, such as Ibuprofen and aspirin if taken in high doses long-term. Certain acne treatments can also cause fertility issues, however, these can usually be reversed once medication ceases. Other lifestyle factors such as drinking, smoking, drug use and obesity can also harm fertility (3,4,5).

4. How often you have sex

It may seem obvious that you need to be having sex to get pregnant, but infrequent sex is one of the most common reasons why couples struggle to conceive. The NHS recommends having regular sex every 2-3 days throughout the month to increase your chances of conceiving within the first 12 months. It is not recommended to wait until ovulation to have sex, as this can increase stress levels in couples. In fact, sperm can live for up to 7 days inside the woman’s body, so having sex before ovulation will give the sperm enough time to travel up the fallopian tube and ‘wait’ for the egg to be released (6).

You can find out more about male and female fertility in our fertility guide.

What is the average amount of time it takes to get pregnant?

According to the NHS, most couples (roughly 84%) will get pregnant within a year if they have regular unprotected sex. Regular sex means having sex every two-three days throughout the month, not just during the time of ovulation.

Women are more likely to conceive within one year if they are under the age of 35 (7):

• Aged 19 to 26 - 92% will conceive after one year and 98% after two years
• Aged 35 to 39 - 82% will conceive after one year and 90% after two years

Conception: a timeline

Many processes are occurring in a woman’s body before, during, and after conception. These can be summarised into three main steps:

1. Ovulation - This usually happens about two weeks before your next period. Each month inside the ovaries, a group of eggs start to grow in small, fluid-filled sacs called follicles. Eventually, one of the eggs erupts from the follicle. After this happens, the follicle develops into something called the corpus luteum and releases a hormone that helps thicken the lining of the uterus, preparing it for the egg to attach. After the egg is released, it moves into the fallopian tube where it stays for about 24 hours, waiting for a single sperm to fertilise it.
2. Fertilisation - If the egg is not fertilised by a sperm, it passes out of the body during the woman’s monthly period, along with the lining of the womb. If one sperm does make its way into the fallopian tube and burrows into the egg, fertilisation occurs and the egg changes so that no other sperm can get in. If the sperm has a Y chromosome, the baby will be a boy. If it has an X chromosome, the baby will be a girl.
3. Implantation - Within 24 hours of being fertilised, the egg starts quickly dividing into multiple cells. The fertilised egg stays in the fallopian tube for about three to four days, then moves slowly through the fallopian tube to the uterus, all the while still multiplying. It will then attach to the lining of the uterus. This is called implantation.

Some women have spotting (light bleeding) for 1 or 2 days around the time of implantation, this is normal. The lining of the uterus gets thicker and the cervix is sealed by a plug of mucus which stays in place for the whole pregnancy. By around 3 weeks, the cells begin to grow as clumps and the baby's first nerve cells have been formed.

When should I take a pregnancy test?

From the time of implantation, your body starts to release a hormone called hCG. This is the hormone detected in both a urine and blood pregnancy test. Some home pregnancy tests can detect hCG as soon as seven days after ovulation, and a pregnancy blood test could pick up hCG in the blood earlier than with a urine test.

If your test comes out positive you should book to see your GP or a midwife straight away. Whilst a positive pregnancy test is usually correct, a negative test may not necessarily mean you are not pregnant. It is recommended to retake the test in a few days if you still think you might be pregnant, and see your GP if you’ve had two negative pregnancy tests but your period still hasn’t arrived.

What are the first signs of pregnancy?

For many women, the first sign of pregnancy will be a missed period. However light bleeding may still occur at the time of implantation.

Every woman will experience pregnancy differently, but some of the first signs of pregnancy include:

• Feeling sick/nauseous
• Feeling tired
• Sore breasts
• Peeing more often
• Strange smells and tastes
• Unusual cravings

Read more about the effects of pregnancy on the body in our guide to pregnancy hormones. 

What can I do to improve my chances?

Whilst in some cases medical treatment may be necessary to improve chances of conceiving, there are things you can do to help improve your fertility. These include:

• Ensuring you are having sex regularly - around every 2-3 days throughout the month is optimal.
• Quitting smoking and drinking - both of these harms not only fertility but also the health of the baby (8). It is recommended women trying to conceive don’t drink at all, and that both the man and woman in a couple quit smoking if they are trying to get pregnant.
• Being a healthy weight - being both overweight and underweight can affect the chances of conceiving (9,10). A healthy BMI should be between 20 and 25. If you are outside of this, taking steps to get within this range through healthy lifestyle changes can increase the likelihood of getting pregnant.
• Reducing stress - trying to get pregnant can be a stressful time for couples, especially if it isn’t happening as quickly as expected. However stress can not only affect your relationship, it can also lower your sex drive. Meditation, regular exercise and spending time outdoors can all help to reduce stress. It is also worth keeping in mind that conceiving naturally can take up to a year or more, so if it hasn’t happened yet, it doesn’t necessarily mean it won't.

If you have been trying to conceive for more than one year, or want to check your fertility status, a fertility blood test is a good place to start. We have a range of female fertility tests to investigate any potential fertility issues as well as overall health when trying to conceive. It is also recommended to see your doctor to discuss any concerns you or your partner have. You can read more about male and female fertility in our fertility guide.

References

1. https://www.ncbi.nlm.nih.gov/pubmed/2059713
2. https://www.ccrmivf.com/egg-quality/
3. https://www.bmj.com/content/354/bmj.i4262
4. https://academic.oup.com/humupd/article/17/1/76/639253
5.https://journals.lww.com/epidem/Abstract/1990/05000/Recreational_Drug_Use_and_the_Risk_of_Primary.3.aspx
6. https://www.ncbi.nlm.nih.gov/pubmed/11980771
7. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC188498/
8. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3312313/
9. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4456969/
10. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4426152/