Threatened Pregnancy (Threatened Miscarriage)

What a threatened miscarriage means

In medical terms, "abortion" here refers to pregnancy loss before 20 weeks, not a procedure. A threatened miscarriage means there are warning signs, usually bleeding, but the pregnancy is still continuing and the cervix (the opening of the uterus) is closed. It does not mean a miscarriage is inevitable.

Types of early pregnancy loss compared

Causes of bleeding in early pregnancy

Often no cause is found. Possible sources include:

• implantation of the pregnancy (implantation bleeding)
• a subchorionic hematoma: blood collecting between the placenta and uterine wall
• the cervix, which bleeds more easily in pregnancy, especially after sex or an exam
• cervical polyps or infections
• an early sign of miscarriage, often from chromosome problems in the pregnancy
• ectopic pregnancy, which must be ruled out

Symptoms

• Vaginal bleeding, from light spotting to bleeding like a light period
• Pink, red or brown discharge
• Mild cramping in the lower belly
• Low back ache

Pregnancy symptoms such as nausea and breast tenderness may continue.

Diagnosis

• Pelvic exam: checks whether the cervix is closed and looks for a source of bleeding.
• Transvaginal ultrasound: confirms the pregnancy is in the uterus, measures its size and checks for a heartbeat. Very early in pregnancy, a repeat scan in 1 to 2 weeks may be needed.
• Blood hCG: if the pregnancy is too early to see, hCG levels are repeated 48 hours apart. A normal rise supports a healthy early pregnancy.
• Blood group and Rh factor: to decide whether Rh immunoglobulin is needed.

Chances of the pregnancy continuing

Most threatened miscarriages do not end in pregnancy loss. Once a heartbeat is seen on ultrasound, the large majority of pregnancies continue. The risk of miscarriage is higher with heavier bleeding, older maternal age, and a slow heart rate or small size on ultrasound. Some studies link early pregnancy bleeding to a slightly higher risk of later complications, such as preterm birth, so your provider may suggest closer monitoring.

Treatment and care

• Watchful waiting: most cases need no treatment. Bleeding usually settles on its own.
• Progesterone: for people with bleeding in early pregnancy who have had a previous miscarriage, vaginal progesterone may modestly increase the chance of a live birth. Ask your provider whether it is appropriate.
• Rh immunoglobulin (anti-D): may be given to Rh-negative people in some situations.
• Rest: bed rest has not been shown to prevent miscarriage, but resting if you feel tired is fine.
• Sex and exercise: there is no strong evidence that sex or normal activity causes miscarriage, but many providers suggest avoiding sex while bleeding.
• Use pads, not tampons, so you can monitor bleeding.
• Pain relief: acetaminophen (paracetamol) at the label dose. Avoid ibuprofen and aspirin unless your provider advises them.

Emotional support

Bleeding in pregnancy is frightening, and waiting for scan results can be very stressful. It is normal to feel anxious. Ask your care team for clear follow-up plans, and seek support from your partner, family or counseling services.

Frequently asked questions

What is a threatened pregnancy?

A threatened pregnancy, also called a threatened miscarriage, is vaginal bleeding in the first 20 weeks of pregnancy while the cervix is closed and the pregnancy is still developing. It is a warning sign, but most pregnancies with a threatened miscarriage continue normally.

What are the chances of survival after a threatened miscarriage?

Most pregnancies continue. Once a heartbeat is seen on ultrasound, the large majority go on to a live birth. Chances are lower with heavy bleeding, older maternal age, or ultrasound findings such as a slow heart rate. Your provider can give a more personal estimate.

Can bed rest prevent a miscarriage?

No. Bed rest has not been shown to prevent miscarriage after a threatened miscarriage. Most early miscarriages are caused by chromosome problems in the pregnancy, which rest cannot change. Resting when tired is reasonable, but normal daily activity does not cause miscarriage.

When should I worry about bleeding in early pregnancy?

Contact your provider for any bleeding in early pregnancy. Seek emergency care for heavy bleeding, soaking a pad an hour for 2 hours, passing large clots, severe one-sided pain, shoulder-tip pain, dizziness or fainting, as these can signal miscarriage or ectopic pregnancy.