What are the characteristics of implantation bleeding?

Implantation bleeding is a slight spotting or short-term bleeding caused by the bursting of small blood vessels when the embryo attaches to the endometrium to continue its development. Its color may be pink, light brown, or pale red.

How Can We Distinguish It from Menstruation?

Women with light or irregular periods may mistake implantation bleeding for menstruation.

There are several key differences:

1. Intensity: Implantation bleeding is much slighter than menstruation. Additionally, menstruation typically starts with slight spotting and increases over time, whereas implantation bleeding remains constant.
2. Duration: Implantation bleeding lasts 1–3 days, whereas menstruation typically lasts 4–7 days.
3. No clots: Implantation bleeding does not contain blood clots.
4. No symptoms: Menstruation is often accompanied by cramps, whereas implantation bleeding is usually asymptomatic.

When Does Implantation Bleeding Occur?

• In a natural cycle, implantation (and thus implantation bleeding) typically occurs between 6 and 10 days after ovulation.
• In IVF procedures, the timing of bleeding depends on the stage of the transferred embryo:
• If a 3–day–old embryo is transferred, bleeding may appear between 3 and 7 days after transfer.
• If a 5–day–old blastocyst is transferred, bleeding may occur between 1 and 5 days after transfer.

Does Implantation Bleeding Confirm Pregnancy?

No, it is not a definitive sign of pregnancy. The only way to confirm pregnancy is with a pregnancy test and, later, an ultrasound.

When Should You See a Doctor?

It is always advisable to consult a gynecologist if there is any doubt. You should seek medical attention especially if bleeding comes with:

• Severe pain.
• Fever.
• Unusual symptoms.
• A history of ectopic pregnancy or recurrent miscarriage.