Types of Miscarriage

A miscarriage is the loss a baby before 20 weeks of pregnancy. After 20 weeks, losing a baby is called a stillbirth.

There are several different types of miscarriage, and although most result in the end of a pregnancy, there are different reasons for why miscarriage happens.

Types of miscarriage are generally categorized depending on the likelihood of the pregnancy continuing. Threatened, inevitable, complete, incomplete or missed miscarriage are the most common terms. And there are different types of pregnancy loss, as well including blighted ovum, molar pregnancy and ectopic pregnancy.

Threatened miscarriage

This happens when a woman has symptoms that she is losing the pregnancy. Often the first sign of threatened miscarriage is vaginal bleeding, with or without cramping. Bleeding may be only slight a light smear on toilet paper after going to the bathroom. Or bleeding can be steady and include clots. During a threatened miscarriage, bleeding can continue for some weeks and then end in miscarriage. Or, bleeding may start, then stop and a normal and healthy pregnancy follows.

Around 30% of women experience an implantation bleed around the time their period is due. This is not a sign of threatened miscarriage, but instead, due to the embryo nestling its way into the bloody lining of the uterus.

Inevitable Miscarriage

This happens after a threatened miscarriage and is when there is no chance of the pregnancy continuing. Bleeding increases, the cervix opens and products of conception may be seen in the blood and clots after they pass from the uterus.

In the case of an inevitable miscarriage, there is nothing which can be done to support the pregnancy continuing. In the past, bed rest was thought to help but currently, there is little evidence to prove this. However, women who are miscarrying are generally advised to take things easy for a while.

Ectopic pregnancy

Ectopic pregnancy happens when the embryo implants outside of the uterus. This is generally in one of the fallopian tubes. The muscles of the uterus are designed to expand and accommodate the growing baby, but the fallopian tubes are not.

Often, the first sign of an ectopic pregnancy is pain and bleeding. An embryo cannot survive when it does not implant in the uterus, and miscarriage is inevitable.

Molar Pregnancy

A molar pregnancy is an abnormal form of pregnancy, where, after fertilisation, the cells of the embryo don t develop as they need to. A molar pregnancy happens when the cells which would normally form a placenta, instead, grow into a clump of abnormal cells. A dilatation and curette (D & C) is needed to remove a molar pregnancy.

Blighted Ovum

A blighted ovum is the reason for a particular type of miscarriage. The pregnancy sac forms, however, there is no baby inside. Another name for a blighted ovum is an anembryonic pregnancy meaning, there is no embryo. Often after a blighted ovum is diagnosed, a D & C is needed to remove the products of conception.

Complete Miscarriage

A complete miscarriage happens when there are no pregnancy products left in the uterus. The pregnancy sac and placental tissue have all been passed. Bleeding during a complete miscarriage can be quite heavy, and there is generally cramping pain as the uterus contracts to expel all the products of conception. Generally a D & C isn t needed if the miscarriage has been complete.

Incomplete Miscarriage

Sometimes, not all the pregnancy tissue is passed and there are still some products which remain in the uterus. Cramping can be strong and continue for a few hours or even days, as the uterus contracts to expel the pregnancy products.

After an incomplete miscarriage, a D & C is often needed to remove all the pregnancy tissues and reduce the risk of infection. Without a D & C, there is a greater likelihood of bleeding continuing after an incomplete miscarriage.

Missed Miscarriage

A missed miscarriage happens when the baby has stopped developing and has died. Pregnancy symptoms tend to become less obvious, because pregnancy hormones stop being produced. Blood loss with a missed miscarriage tends to look like old brown blood, rather than bright red. A missed miscarriage is generally diagnosed by ultrasound (scan).

Recurrent or Repeated Miscarriage

Some women have a history or repeated or recurrent miscarriages. The general recommendation from health care providers is for women to seek specialist support if they've had three or more miscarriages. Causes for recurrent miscarriage can vary, though genetic and hormonal factors are often the reason.

Stillbirths

Stillbirth happens when a baby has died during the pregnancy or, during labour or birth. The term stillbirth applies at any time from 20 weeks of pregnancy, right up to the day of birth.

If a baby weighs more than 400 grams it is considered a stillbirth.

I think I've had a miscarriage but I've stopped bleeding. Do I still need to see my doctor?

Yes, it's always recommended to see a doctor or healthcare professional during or after a miscarriage. Often a scan is ordered to see if the miscarriage is complete or, there are any products of conception still in the uterus. Women who have a negative blood group Rh-negative, may need to have an injection of Anti D to prevent complications with future pregnancies.

What are the chances of me having any type of miscarriage?

Miscarriage is fairly common; around 1 in 5 women who have had a confirmed pregnancy will have a miscarriage before 20 weeks gestation. However, some women miscarry before they even realise they are pregnant. This makes it difficult to be 100% sure what the true likelihood of miscarriage really is.

Written and reviewed by Jane Barry, midwife and child health nurse on 9/02/20