What is Implantation?

Implantation is when a fertilized egg cell attaches to the wall of the uterus in early pregnancy. In this post we’ll delve deeper into implantation, when it happens, what implantation bleeding looks like and more. Read on to learn all about implantation, and find ways you can get to know your body better during early pregnancy.


When does implantation occur? 

Implantation happens very early on in pregnancy, soon after the female egg cell has been fertilized by sperm in the fallopian tubes. The fertilized egg then travels down the fallopian tubes, transforming from a single cell into a ball of multiple cells. This collection of cells then implants into the uterus lining. Usually, implantation occurs eight to nine days after ovulation (when the egg cell is released from an ovary). However, it can happen anywhere between six to twelve days after ovulation.

Interestingly, while many methods of hormonal birth control work by stopping ovulation (such as the hormonal IUD or the pill), some forms of birth control also work by preventing implantation from happening (such as the copper IUD).  

Implantation symptoms: what does implantation feel like?

Many women won’t experience any physical sensation around implantation. In fact, you might not realize implantation has happened - and the first sign of pregnancy might be your missed period. 

However, some women may experience cramps around implantation. These feel different to period cramps. They are described as being less intense, with a prickling, pulling or tingling sensation. Some women also experience ovulation pain, which happens around ovulation, preceding implantation by about a week.

Since you might not feel anything around implantation, it’s worth being aware of the other common symptoms of early pregnancy. These include:

  • Sore or swollen breasts
  • Tiredness
  • Nausea and/or vomiting
  • Cravings to certain foods 
  • Headaches
  • Constipation
  • Mood swings
  • Feeling faint or dizzy
  • Raised body temperature

Implantation bleeding or period

As well as the symptoms listed above, you may experience a type of spotting called implantation bleeding. Implantation bleeding is caused by the fertilized egg coming into contact with blood cells in the uterus lining as it implants into the uterine wall. Since implantation bleeding happens around the time your period is due, it can be tricky to tell sometimes if you’re experiencing menstrual bleeding or an implantation bleed. 

Since the symptoms of PMS are also similar to those in early pregnancy, this can make things more confusing. There are a couple of subtle differences to help us tell implantation bleeding and menstruation apart… 

What does implantation bleeding look like? 

One of the ways to differentiate whether it’s implantation bleeding or period blood is the appearance of the implantation bleed. Implantation bleeding looks a little different to most menstrual bleeding, as it’s often pink or brown in color, as opposed to the bright red of menstrual blood. 

There’s also usually a smaller quantity of blood than with a steady menstrual flow. However, since some women may experience very light periods, it can make it harder to tell the two apart.

How long does implantation bleeding last?

If you get implantation bleeding, it should occur around a week after ovulation, before your next period is due. Shorter and lighter than the average period, implantation bleeding usually lasts about one to three days. If you experience heavy bleeding or clotting, or have any concerns about your reproductive health, we always advise you to contact your healthcare professional. 

Does everyone have implantation bleeding? 

The answer is no. While implantation bleeding is more common than implantation cramps, most women are likely to not experience any implantation symptoms at all. All of our bodies are different, so our experiences of pregnancy will differ from woman to woman. However, knowing our bodies better allows us to understand what is normal for us and what to look out for. Why not check out our list of things to know before planning a pregnancy for more info?

How soon can I take a pregnancy test after implantation?

A pregnancy test is unlikely to be accurate on the day of implantation, as the hormones needed to detect pregnancy aren’t being produced yet. Pregnancy tests are most reliable from the first day of your missed period. However, some tests may be accurate four or five days before your period is due (check the manufacturer’s instructions). If you don’t know when you’re period is meant to arrive, or your cycles are irregular, we suggest waiting three weeks after you’ve had unprotected sex before you take a pregnancy test. If you need to stock up, pregnancy tests are available online from our webshop. 

Another indication of early pregnancy is increased body temperature - this changes throughout our cycle. It rises after ovulation, and then, if we aren’t pregnant, hormones cause our body temperature to drop, cueing the uterus lining to shed, prompting our period and the start of a new cycle. However, if we are pregnant, the hormone progesterone stays high, keeping our body temperature elevated. These changes in temperature are very subtle, but can be found by regularly measuring with a basal body thermometer (a thermometer that shows two decimal places).

Know your fertility

Thanks for taking the time to read about implantation, we hope you’ve learned something new! No matter where you are in your fertility journey, Natural Cycles can help you get to know your body better. 

Our FDA Cleared app has a mode for both planning pregnancy and a mode for natural birth control. Both options utilize the science of basal body temperature, paired with an algorithm that can predict your unique fertile window, giving you daily fertility statuses that are unique to you. Ready to learn more about your body?

Discover Natural Cycles° today

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Written By

Jennifer Gray

A writer with a passion for women’s health, Jennifer Gray has years of experience writing about various reproductive health topics including birth control, planning pregnancy, women’s anatomy, and so much more.

Jack in a suit and tie holding a microphone and giving a presentation.

Scientifically Reviewed

Jack Pearson

With 10 years of experience working in the field of fertility, Dr. Jack Pearson is Natural Cycles’ in-house expert. As Medical Affairs Manager, he dedicates his time to conducting groundbreaking research and educating healthcare professionals.

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