There are various reasons a person may experience spotting in early pregnancy. For instance, spotting at 6 weeks may be from hormonal changes.

People may experience light bleeding during early pregnancy, known as spotting. This is a common occurrence but can be a sign of a more serious problem.

In this article, we discuss the common causes of spotting, what it may look like, and when to contact a doctor.

About a quarter of pregnant people experience bleeding during the first trimester. Although bleeding is a possible sign of early pregnancy loss, it does not mean this will happen.

Several other conditions and factors, including normal hormonal shifts, may cause spotting in early pregnancy.

The most common causes of spotting in early pregnancy include:

Subchorionic hematoma

A subchorionic hematoma happens when blood builds up near the chorion, the fetal membrane next to the placenta. The bleeding may also appear between the uterus and the placenta.

Some people may also refer to this as a subchorionic hemorrhage.

Subchorionic hematoma is the most common cause of bleeding in the first trimester of pregnancy, accounting for around 11% of cases.

A subchorionic hematoma is not a pregnancy loss. Many pregnant people with this type of bleeding have no further complications during their pregnancy.

People who experience a subchronic hematoma are at a higher risk of early pregnancy loss.

Ectopic pregnancy

In an ectopic pregnancy, a fertilized egg implants outside the uterus, often in the fallopian tubes. A person may still have pregnancy symptoms or get a positive pregnancy test.

The pregnancy, however, cannot survive. It can rupture and cause life threatening bleeding or a dangerous infection if it continues to grow.

An ectopic pregnancy can cause spotting as the pregnancy grows. In the case of a rupture, internal bleeding may get progressively heavier over several hours.

Cervical irritation

The cervix, the doughnut-shaped entry to the uterus, increases its blood supply during pregnancy. This means it is more likely to bleed from irritation, such as after sex or a pelvic exam. Light spotting after any form of vaginal penetration is a possible sign of cervical bleeding.

Cervical bleeding during pregnancy is typically not a cause for concern. However, a serious injury to the cervix, such as an assault or trauma, might cause more severe cervical bleeding.

These injuries can cause infections and other serious complications. It is important to contact a doctor following any traumatic injury to the cervix or vagina.

Learn more about changes to the cervix in early pregnancy here.

Pregnancy loss

Vaginal bleeding is the most common sign of pregnancy loss. The medical term for pregnancy loss in the first 23 weeks is miscarriage.

However, around half of people that experience light bleeding during early pregnancy do not lose their pregnancy.

Any pregnant person who has concerns about their pregnancy should speak with a doctor about risk factors and how to minimize them.

Hormonal shifts

Around week 6–8 of pregnancy, a luteal-placental shift happens. This is when the placenta develops enough to produce hormones that sustain the pregnancy. Before this change, the corpus luteum — a group of cells that forms during ovulation — produces pregnancy hormones.

This hormonal change sometimes triggers a temporary drop in the hormone progesterone. This shift may cause spotting or even bleeding as heavy as a period. As long as the placenta begins producing enough progesterone, the pregnancy can safely continue, and a pregnancy loss will not occur.

Implantation bleeding

Implantation happens when a fertilized egg embeds in the lining of the uterus. This marks the beginning of pregnancy. Some people notice spotting shortly after implantation. However, the body does not begin producing the pregnancy hormone human chorionic gonadotropin (hCG) until after implantation.

A person is not pregnant until after implantation, and a pregnancy test cannot usually detect pregnancy until several days after implantation. So, bleeding that appears after a person already knows they are pregnant is not implantation bleeding.

Implantation bleeding is usually brown. Some people may mistake the bleeding for their monthly period because it usually occurs around the time a person expects their period.

The flow of implantation bleeding is often lighter and shorter than a period, so people who experience unusual bleeding after having sex should consider the possibility of pregnancy.

A doctor or other healthcare professional may conduct or order numerous tests to diagnose bleeding.

Ultrasound

An ultrasound can diagnose a subchorionic hematoma. It can also tell a healthcare professional the location of the pregnancy, helping in the detection of an ectopic pregnancy.

Doctors can also use ultrasound scans to assess the viability of the pregnancy. If the embryo is growing correctly, and there is a sufficiently strong heartbeat, this suggests that the pregnancy will continue and the risk of pregnancy loss is low.

An ultrasound can also examine other pelvic organs to check for causes of bleeding. For example, an ovarian cyst may cause bleeding.

Blood tests

Blood tests can measure levels of the pregnancy hormone hCG. Low hCG may suggest that a pregnancy is not developing correctly or is in its early stages.

Some healthcare providers also check progesterone levels. Low progesterone may cause temporary bleeding, while very low progesterone may be a sign of an abnormal pregnancy.

While many people who experience bleeding have healthy pregnancies, it is important never to treat bleeding as usual.

Bleeding can be a critical symptom of several pregnancy-related symptoms, and prompt treatment for conditions such as ectopic pregnancy can save lives.

People should speak with a doctor about any bleeding early in pregnancy. While the bleeding may be harmless, it is impossible to diagnose its cause without blood work, an ultrasound, or other diagnostic tests.

Bleeding from a ruptured ectopic pregnancy can endanger the life of the pregnancy carrier. While many pregnancy losses pass on their own, some require treatment to prevent excessive bleeding and infection.

If a person experiences light bleeding at any time, they should contact a midwife, doctor, or another healthcare professional.

A pregnant person should also visit an emergency room if:

  • they develop a fever
  • bleeding gets heavier over several hours
  • bleeding is heavy, similar to a period
  • there are large clots in the blood
  • they have cramps
  • they have severe pain in the abdomen
  • they feel dizzy or lightheaded

Prompt medical care can be lifesaving. Even when there is no serious problem, the right care can offer peace of mind.

If a pregnant person experiencing spotting has Rhesus-negative blood, a doctor may prescribe RhoGAM. This treatment can help prevent a condition known as erythroblastosis fetalis.

Many people panic when they bleed during pregnancy, especially if they have a previous history of pregnancy loss. Seeking prompt care is the fastest way to ease anxiety and get clear answers.

It is not advisable for people to try to self-diagnose bleeding or assume that bleeding means a pregnancy loss. Quick tests can usually diagnose the cause, and prompt treatment can prevent possible complications.