Implantation Bleeding

Implantation bleeding is when the implanted embryo (fertilized egg cell) disrupts the blood vessels of the endometriosis (uterine wall). Approximately, about 1 out of 3 (20 – 30%) women experience this.

It is totally harmless on both parties; mothers – to – be who experience this will continue to have healthy and normal pregnancies. This type of bleeding is also referred to as:

  • Vaginal spotting
  • Light bleeding

In line with this, implantation is when the successfully fertilized egg cell attaches itself to the uterine lining. It is one of the earliest indicators of pregnancy [prior to morning sickness].

In addition to that, here is how implantation takes place:

  1. The embryo begins to divide and grow.
  2. Later on, the embryo will send out chemical signals to prepare a woman’s body for pregnancy.
  3. Once received, the endometriosis begins to grow and mature as to protect the embryo for 9 months.
  4. Around 6 – 12 days after fertilization, the developing embryo travels down from the uterus down the ampulla of a fallopian tube.
  5. Then the embryo attaches and burrows itself to the endometrium which will cause the implantation bleeding. Once the embryo has settled, begins to rely on the mother’s body that is, getting the supply of nutrients and oxygen via an umbilical cord.

Implantation bleeding versus menstrual bleeding

A lot of women are confused whether they are experiencing implantation bleeding or just a normal menstrual cycle. In fact, there are no sure signs or conclusive test available.

With that being said, enlisted below are the following characteristics to distinguish which is which:

Pregnancy week by week


The flow is considered as the primary distinction between implantation bleeding and menstrual bleeding (menstruation/ menstrual period). With that being said, below are ways to distinguish the two:

  • Implantation bleeding is only characterized by light bleeding and will stay that way [it is very light that it is not enough to soak a panty liner], while a menstrual flow begins with light bleeding and gets heavier during the course of the period
  • Implantation bleeding does not contain blood clot – like discharge unlike menstrual bleeding


  • The consistency of menstrual bleeding gets heavier within a day or two unlike implantation bleeding [which has a steady light flow]
  • Implantation bleeding goes on and off while the consistency of menstrual bleeding is stable and continuous throughout the duration of a period


The color of implantation bleeding ranges from pinkish, brownish to dark brown blood. In line with this, women claimed that the brownish discharge has a strong smell.

The implantation discharge becomes brownish in color because the blood takes time to move out from the uterus to the vaginal opening [sometimes the blood is clogged inside the uterus], which causes it to become old and brownish in color.

Rarely, the color of implantation bleeding appears light [or fresh] red. This indicates that the blood has just shed from the uterine lining.

On the other hand, menstrual bleeding is characterized by fresh red color of blood.

Level of pain

Basically, implantation bleeding and menstruation can cause a level of pain (cramps). Pregnancy implantation causes pain once the fertilized egg burrows and attaches itself to the uterine wall. This then causes the uterine muscles to contract, which brings pain.

With that being said, enlisted below are ways to distinguish how the level of pain brought by menstruation differs from the level of pain caused by pregnancy implantation:

  • Pregnancy implantation pain only involve dull cramps while menstrual pain is accompanied by a sharp sensation
  • The level of pain brought by implantation does not intensify unlike menstrual cramps. In line with this, intensifying pain is also associated with other symptoms such as chills and fever
  • Implantation pain may last from a few hours to day while menstrual cramps vary from woman to woman. If the pain persists, it could be a sign of various medical conditions such as bladder infection and appendicitis


Implantation bleeding usually occurs 5 – 12 days after conception, as the upcoming menstrual cycle approaches. Because of that, a lot of women are confused whether they are experiencing implantation bleeding or just another menstrual period.

With that being said, enlisted below are the ways to distinguish the timing of implantation bleeding from a normal menstrual period:

  • If a woman last had an unprotected sexual intercourse for about 2 weeks ago, any bleeding thereafter is probably her next menstrual period
  • If a woman who had unprotected sexual intercourse experienced light bleeding during the time of her next cycle, then it may probably be implantation bleeding
  • Implantation bleeding usually occurs when a woman last had sex for a month or 2 unlike a menstrual period which follows a cycle [either regular or irregular]
  • Implantation bleeding usually occurs about 6 – 12 days after ovulation while a menstrual period occurs 2 weeks after ovulation
  • Implantation bleeding comes a few days to a week ahead of the next menstrual cycle
  • Implantation bleeding occurs a week after ovulation

Accompanied pregnancy symptoms

Implantation bleeding and a menstrual period are associated with pregnancy symptoms. To know which is which that a woman experiences, enlisted below are the pregnancy symptoms brought by:

Implantation bleeding

  • Nausea and vomiting
  • Over – fatigue
  • Changes in bathroom routine such as frequent urination and colon congestion
  • Dizziness

Menstrual period

  • Breast soreness and pain

Either implantation bleeding and/or a menstrual period

  • Mood swings (caused by hormonal changes)


  • A menstrual cycle typically last for 3 days to a week while implantation bleeding only last for 1 – 2 days


  • Implantation bleeding only contains a couple of drops while a menstrual period consist of so much more

Causes of implantation bleeding

Aside from implantation itself, implantation bleeding can stem from a variety of reasons; some are harmless while some, unfortunately, are severe. Enlisted below are the causes of vaginal spotting:


Many women experience implantation bleeding in the middle of a menstrual cycle or during ovulation. Ovulation refers to the rupturing of the follicles to release the mature egg cell which will travel down the fallopian tube for it to be available for fertilization.

Uterine fibroids

Fibroids refer to the non – cancerous tumors that grow inside the uterus. With that being said, uterine fibroids (also called leiomyoma or simply, myoma) are common non – cancerous growth in the uterine wall during childbearing years.

The presence of uterine fibroids can cause bleeding in between menstrual periods.

Pelvic inflammatory disease

Pelvic inflammatory disease (PID) is an infection of the female reproductive organs which affects the fallopian tubes, ovaries, uterus, which results to abnormal bleeding and/or vaginal spotting. PID usually comes along with symptoms like:

  • Fever
  • Stomach pain in the lower quadrant

Pelvic examination

Irritation caused by a pelvic examination in the cervix can cause vaginal spotting.

Polycystic Ovary Syndrome

Women who suffer from PCOS experience irregular menstrual cycles or no menstrual period at all. In some cases, other women experience very light vaginal bleeding.

Polycystic ovary syndrome (PCOS) is an endocrine system disorder.  PCOS is caused by hormonal imbalances that delay the process of ovulation.

Insertion of an intrauterine device

Insertion of an intrauterine device can surely cause vaginal bleeding, specifically irregular and/or heavy bleeding.

Intrauterine device (IUD) refers to the long – lasting reversible contraceptive device that is inserted into the uterus. IUD [either] contains copper and/or levonorgestrel (a manufactured hormone used to prevent pregnancy). This medical instrument is slim, T – shaped in appearance, and is made in plastic.

Various reproductive infections

Various reproductive infections like sexually transmitted diseases can cause vaginal spotting in between menstrual periods.

Certain reproductive cancers

Vaginal bleeding is sometimes linked to certain cancers of the reproductive system such as:

  • Cervical cancer
  • Ovarian cancer

Sexual intercourse

Sexual intercourse can cause vaginal bleeding due to the following reasons:

  • Hormonal changes during the onset, or during the course of pregnancy
  • Irritation and/or inflammation

On the bright side, vaginal bleeding caused by sexual intercourse does not need any [or further] treatment.

When to see the doctor

A mother – to – be must always consult a medical practitioner once vaginal bleeding occurs [light or heavy, with or without pain]. Pregnant women can bleed for a variety of reasons aside from implantation, and it may be a sign of something worst such as:

Light bleeding while gestating

Light bleeding while gestating is often a normal symptom, this is usually caused by routinely habits such as:

  • Cervical irritation due to pelvic exam and/or sexual intercourse
  • Vaginal infection

Ectopic pregnancy

Some expectant mothers may experience mild cramps during implantation but if the cramping persist or becomes worst, it may be a sign of ectopic pregnancy.

Ectopic pregnancy is when the fetus implants and develops outside the uterus, typically in the ampulla of a fallopian tube.

Molar pregnancy

Molar pregnancy is the outcome of a genetic error during the course of fertilization. This will eventually lead to abnormal tissue growth inside the uterus. Rarely, this pregnancy complication includes a developing embryo.

In addition to that, there are 2 types of molar pregnancy namely:

  • Complete molar pregnancy – involves an empty placenta since a sperm cell has fertilized an empty egg cell
  • Partial molar pregnancy (also called as partial mole) – is when the embryo (fertilized ovum) partially develops or does not develop at all. Instead, a hydatidiform mole (grape – like cysts) develops inside the uterus


If a potential or confirmed pregnancy comes along with heavy bleeding, an expectant mother may be experiencing a miscarriage. As a matter of fact, about 15% of all confirmed pregnancies come to an end during the first few months.

Miscarriage is when pregnancy has ended on its own within the first 20 weeks. It is considered as the most common type of pregnancy loss.

Unable to confirm pregnancy

A trying – to – conceive woman may experience a number of symptoms that may confuse her if she is positively pregnant or not. The sure way to confirm pregnancy is to visit a medical practitioner (particularly obstetrician – gynecologist).

With that being said, an obstetrician – gynecologist will check a woman’s stained [with blood] underwear.