Differences Between Menstruation and Implantation Bleeding

Implantation bleeding is an issue often confused with menstruation. Learn the differences between menstruation and implantation bleeding.
Differences Between Menstruation and Implantation Bleeding

Last update: 08 May, 2021

Implantation bleeding is a slight loss of blood that occurs early on in pregnancy, but it doesn’t happen to all women. It occurs on the day your menstrual cycle should begin and, therefore, is often confusing for many soon-to-be-mothers. Keep reading to find out the differences between menstruation and implantation bleeding.

One of the most obvious signs of pregnancy is not menstruating. However, some women may still experience bleeding due to implantation bleeding. As its name implies, this condition involves bleeding, but it’s not from your menstrual cycle. 

Implantation bleeding is also known as a “false period.” For those who already think they’re pregnant, this bleeding may lead them to believe they had a miscarriage. To avoid confusion, it’s best to get well informed. This will help you avoid any misunderstandings.

Implantation bleeding

Woman with cramps.

Implantation bleeding is a normal condition in a healthy pregnancy. It occurs between 6 and 12 days after the ovum has been fertilized. This date should, more or less, coincide with your normal menstrual cycle. 

Usually, this condition is accompanied by cramps, but they’re less intense than the ones you have when you’re menstruating. Also, women may experience headaches, nausea, mood swings, breast tenderness, lower back pain, abdominal swelling, and fatigue.

Typically, implantation bleeding doesn’t follow any type of pattern. A woman who has already had children may experience this condition with some of her pregnancies and not others. Sometimes, the woman will only have a drop of blood and other times it will be the same amount as a light period.

From ovum to embryo

When fertilization occurs, the joining of the egg and the sperm will create a zygote. This is the technical name for a fertilized egg. In as little as 72 hours, the zygote turns into a morula, which is a segmented zygote. Four to five days later, the morula turns into a blastocyst.

The blastocyst, or blastula, has one group of outer cells and another group of inner cells. The former will become the protective membrane and the latter will become the embryo. It isn’t an embryo until the blastocyst has implanted itself in the uterus. 

Approximately one week after fertilization, the blastocyst begins to create extensions. These will allow it to adhere to the lining of the uterus. In this early stage, the uterus is highly irrigated and bleeds easily. Therefore, implantation can cause bleeding.

Differences between menstruation and implantation bleeding

Woman on her period.

This type of bleeding is a light spotting, and we usually only notice a small amount on underwear or toilet paper. Only rarely will it be heavier than that. The color can be dark pink or brown, but not red. It doesn’t have any clots and it can last from a few hours up to three days.

With implantation bleeding, there’s no gradual blood flow like with menstruation. It comes and goes intermittently, but it will stay light and won’t get heavier.

If you think you’re pregnant and the bleeding is a more intense color, or it suddenly increases, you should see a doctor. In some cases, this is a symptom of a miscarriage, a sign of ectopic pregnancy or it may be a sign of a molar pregnancy. It may also be a symptom of another health problem.

Confirmation of pregnancy

At first, it’s very difficult to tell whether or not you’re pregnant. For that reason, it will be difficult to figure out if your bleeding is from implantation bleeding, a miscarriage, or another issue. That’s why you should confirm your pregnancy as soon as possible.

The most reliable pregnancy tests can be done during the first week of gestation. These tests are done in laboratories and have a high degree of accuracy. In contrast, home tests have a lower degree of reliability when performed shortly after fertilization.

All of these tests measure the level of the hormone chorionic gonadotropin (HCG). This hormone is present in the blood and urine. Home tests can be done if you’re experiencing implantation bleeding, but it’s best to wait a week for more reliable results.

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