Threatened Miscarriage: Tests, Treatment and What Comes Next

What a threatened miscarriage means

"Threatened" means there is a sign of possible miscarriage (bleeding) but no loss has happened. The cervix (neck of the womb) is closed and an ultrasound, if done, shows a pregnancy that is still developing. It is different from an inevitable miscarriage, where the cervix has opened, and from an incomplete or complete miscarriage, where tissue has passed.

Our threatened pregnancy page compares all the types of early pregnancy loss and the many causes of bleeding. This page focuses on the tests you will have, what the results mean and what treatment is offered.

Common causes of bleeding in a threatened miscarriage

Often no cause is found. Possibilities include:

• bleeding from the edge of the developing placenta
• a subchorionic hematoma, a collection of blood between the womb wall and the pregnancy sac
• implantation bleeding very early in pregnancy
• a sensitive cervix after sex or an exam, cervical polyps or infection
• the beginning of a miscarriage that will continue

Symptoms

• spotting or bleeding that may be pink, red or brown
• mild cramps or a dull ache in the lower belly or lower back
• pregnancy symptoms such as nausea and breast tenderness usually continue

Bleeding amount does not reliably predict the outcome. Many people bleed quite heavily and continue their pregnancy, while losses can occur with little bleeding.

The tests you will have

Transvaginal ultrasound

A probe placed in the vagina gives the clearest view in early pregnancy. It answers three questions:

1. Is the pregnancy in the womb? This rules out ectopic pregnancy, a pregnancy outside the womb that can be dangerous.
2. Is there a heartbeat? Cardiac activity is usually visible from about 6 to 7 weeks.
3. Is the size right for the dates?

Doctors use strict cut-offs before diagnosing a loss, to avoid any chance of ending a viable pregnancy. When findings are uncertain, they always repeat the scan.

hCG blood tests

When the scan cannot yet show the pregnancy clearly, two hCG (pregnancy hormone) tests 48 hours apart show the trend. In a healthy early pregnancy, hCG usually rises by at least about 35% to 50% over 48 hours. A falling level suggests miscarriage. A slow rise or plateau can suggest an ectopic or failing pregnancy.

Blood type and Rh factor

If you are Rh negative, your immune system could react against an Rh-positive baby's blood. Rh immune globulin (RhoGAM) prevents this. ACOG guidance from 2024 says it can usually be skipped after a miscarriage or abortion before 12 weeks, and it is generally given for bleeding at 12 weeks or later. Your provider will advise what is right for you. See Rh disease.

Treatment

There is no treatment that stops a miscarriage that is already underway, and most threatened miscarriages need none.

• Progesterone: A large trial found that vaginal micronized progesterone increased live births in people with early pregnancy bleeding who had had one or more previous miscarriages, with the greatest benefit after three or more. NICE recommends offering it in that situation once an intrauterine pregnancy is confirmed. It has not been shown to help people without a previous miscarriage.
• Bed rest: does not prevent miscarriage and is not recommended.
• Pain relief: acetaminophen (paracetamol) is preferred in pregnancy. Avoid NSAIDs such as ibuprofen unless your provider advises them.
• Use pads, not tampons, so you can monitor bleeding and reduce infection risk.
• Sex: there is no evidence that sex causes miscarriage, but many providers suggest waiting until bleeding has stopped.

Chances of the pregnancy continuing

• If a heartbeat is seen and the embryo is the expected size, roughly 90% or more of pregnancies continue.
• Chances are lower when bleeding is very heavy, the heart rate is slow, there is a large hematoma, the embryo is smaller than expected, or you are over 35.
• Most miscarriages are caused by chromosome problems in the pregnancy and are not caused by anything you did.

Effects later in pregnancy

People who had a threatened miscarriage have a modestly higher chance of later complications, including preterm birth, waters breaking early, placental problems and lower birth weight. Your provider may suggest closer monitoring, but most go on to have healthy pregnancies and babies.

Coping

Bleeding in early pregnancy is frightening, and waiting days for a repeat scan is hard. Ask your provider exactly when to call and what follow-up is planned. Support from your partner, family or a pregnancy loss charity can help, whatever the outcome.

Frequently asked questions

What are the chances of miscarriage after a threatened miscarriage?

If an ultrasound shows a heartbeat and normal growth, about 90% or more of pregnancies continue. The risk is higher with heavy bleeding, a large subchorionic hematoma, a slow heart rate or a smaller-than-expected embryo. Before a heartbeat is visible, the outlook is less certain until a repeat scan.

Does progesterone help with threatened miscarriage?

It helps a specific group. In people with bleeding in early pregnancy who have had at least one previous miscarriage, vaginal progesterone modestly increased live birth rates, especially after three or more losses. It has not been shown to help those without a previous miscarriage.

Is bleeding at 8 weeks pregnant normal?

Bleeding at 8 weeks is common and often settles without harm, but it should always be checked. An ultrasound will usually show whether the pregnancy is in the womb and has a heartbeat. Heavy bleeding, severe pain or fainting needs emergency care.

Should I stay in bed during a threatened miscarriage?

No. Bed rest has not been shown to prevent miscarriage. You can carry on with normal daily activities as you feel able. Avoid strenuous exercise if it worsens bleeding or pain, and rest when you need to.

How long does bleeding last with a threatened miscarriage?

It varies. Some people have a single episode of spotting, while others bleed on and off for days or weeks, especially with a subchorionic hematoma. Bleeding that gets heavier, comes with stronger cramps or passing tissue needs prompt review.