How many days before period does implantation bleeding occur

When you're trying to conceive, it's hard to wait the two weeks or so between your fertile days and taking an at-home pregnancy test. During this period of anticipation, it's natural to interpret the slightest change in your body as a possible sign of pregnancy. The only thing worse than getting your hopes up because you feel a little more tired or out of breath than usual, is to mistake implantation bleeding for your period and assume you're not pregnant. So what color is implantation bleeding? It's time you learn to tell the difference between this early sign of pregnancy and your regular menstrual cycle.

Over email, Romper interviewed three OB-GYNs about implantation bleeding. Their descriptions each differ slightly, but all agree that implantation bleeding is lighter in flow and a different color than your regular period. It's "usually brown," says Miao Crystal Yu, OB-GYN at Saddleback Medical Center in Laguna Hills, California. Yu elaborates that implantation bleeding is "a little bit of brownish spotting that occurs when the embryo implants." This matches the characterization Gerardo Bustillo of MemorialCare Medical Group in Fountain Valley, California, gives implantation bleeding, too. According to Bustillo, implantation bleeding doesn't necessarily have a specific color, but "generally the spotting or bleeding is light." OB-GYN Yen Tran of Orange Coast Medical Center in Fountain Valley, California, adds that implantation bleeding may look like "pinkish/rusty old brown bloody discharge."

To distinguish implantation bleeding from a normal period, it's helpful to understand the process behind it. According to Tran, "After fertilization occurs in the fallopian tubes around the time of ovulation, the embryo travels down the fallopian tube to attach to the wall of the uterine cavity. During the attachment progress, some blood vessels break down." The broken blood vessels lead to the old blood (i.e. brownish) spotting you may find in your underwear. However, Bustillo notes that implantation bleeding "remains an unproven hypothesis" and "does not occur in the majority of pregnancies."

Timing is also important when you're trying to pinpoint the cause of bleeding. Bustillo and Tran say implantation bleeding occurs approximately 10 to 14 days after conception, while Yu gives an earlier estimate of three to seven days post-conception. Since your period isn't due until about two weeks after ovulation, you can probably guess implantation bleeding if you experience light spotting much earlier than that. It can be harder to guess if the bleeding overlaps with when you expect your period. Luckily, there are other differences to help you compare a normal period with implantation bleeding.

When asked how a woman can tell whether she is experiencing implantation bleeding or a regular period, Yu says, "Implantation bleeding is much lighter, usually lasting one to two days, not requiring the patient to change pads. If in doubt, talk to your OB-GYN and confirm the diagnosis with blood work or ultrasound." Bustillo also notes that a pregnancy test may be the best way to confirm the cause of your bleeding. "Implantation bleeding, when it does occur, coincides with the time of an anticipated menses. Therefore it can be confusing to know exactly what is going on. Generally, implantation bleeding is spotting only, while a menstrual period is heavier. If the bleeding is accompanied by potential early pregnancy symptoms such as fatigue, nausea/vomiting, and frequent urination, a pregnancy test would be indicated to solve the dilemma."

Finally, Tran agrees that implantation bleeding is usually shorter than menstruation and may be accompanied by early pregnancy symptoms. "Most periods last about four to seven days [and are] heavier with a bright red color blood, whereas implantation bleeding comes a few days sooner than the next expected period and only lasts for a few hours to two days only, along with signs like breast tenderness, mild cramping, headache and mild nausea."

When a fertilized egg attaches to the wall of the uterus, where it can begin growing, some light spotting may occur. This is called implantation bleeding, and it can be one of the earliest clues that you are pregnant. Some women don’t experience this type of bleeding, and some simply don’t notice it. If it happens, it doesn’t indicate a problem with your pregnancy. If you’re wondering if you might be pregnant, take our Am I Pregnant? quiz for a little fun and grab a home pregnancy test.

Is It Implantation Bleeding or My Period?

It’s possible to mistake implantation bleeding for a very light and early period at first. However, there are some differences to pay attention to. Although every woman’s period is different, it’s still possible to guess that it's implantation bleeding by the color and amount of bleeding, and by where you are in your menstrual cycle, as well as by looking out for other early signs of pregnancy — more frequent bathroom trips, fatigue, and nausea (i.e., morning sickness).

These are the main signs and symptoms of implantation bleeding compared to a period:

  • The amount of blood. Implantation bleeding isn’t heavy; it’s more like a discharge or light spotting that’s about a few drops of blood on your underwear.

  • The color of the spotting. The blood from implantation is more of a pinkish or brown color, rather than a bright red some women normally see during a period.

When Does Implantation Bleeding Happen?

You may notice implantation bleeding around 10 to 14 days after conception, when a fertilized egg becomes attached to the lining of your uterus. Keep in mind that conception may not occur on the same day you had sex. Sperm can live as long as five days inside a woman’s reproductive tract, and conception might not occur for several days after sex.

Should I Take a Pregnancy Test During Implantation Bleeding?

You can take a home pregnancy test during implantation bleeding. Keep in mind that the pregnancy hormone human chorionic gonadotropin (or hCG) that pregnancy tests detect only starts being produced in your body the moment the fertilized egg is implanted in the uterus — which is the trigger for implantation bleeding. The earlier you take the test, the less hCG there is to detect, meaning that the test may not yet be accurate. If you have the patience to wait, you’ll get a more accurate test result if you wait until after the first day of your missed period.

If you get a positive test result, schedule an appointment with your healthcare provider to confirm your pregnancy. And you can get an estimate of when to expect your baby by using our handy tool to calculate your due date.

Should I See a Doctor?

Implantation bleeding is generally nothing to be concerned about, but it’s a good idea to talk to your healthcare provider about any bleeding you experience during pregnancy. Although light bleeding in early pregnancy can be totally normal, there are some reasons for bleeding in early pregnancy that need to be addressed immediately. These can include infection, miscarriage, or ectopic pregnancy.


How many days before period is due is implantation?

Implantation bleeding tends to occur during the week before you would expect your period, or about six to 12 days after conception. This is around the same time a fertilized egg would be attaching itself to the uterine lining.

How can I tell if it's implantation bleeding?

Implantation bleeding is more likely to be a pinky-brown color. Menstrual bleeding, on the other hand, may start off light pink or brown, but it soon changes into crimson red. Strength of flow. Implantation bleeding is usually super-light spotting.

Does implantation bleeding occur before expected period?

Implantation bleeding can occur about 10-14 days after conception when the fertilized egg attaches to the interior lining of the uterus. This movement of the egg can result in light bleeding or spotting, which is completely normal and should not require any kind of medical attention.