Miscarriage: Signs, Symptoms & Causes

miscarriage, abdomen, pregnancy
Ten to 25 percent of clinically recognized pregnancies end in miscarriage.
Credit: Maridav | Shutterstock

A miscarriage is the loss of pregnancy before the 20-week mark in the pregnancy. Because the embryo or fetus cannot live on its own that early in the pregnancy, the pregnancy is aborted. The medical term for a miscarriage is spontaneous abortion.

Many people don't realize that miscarriages are fairly common. Ten to 25 percent of clinically recognized pregnancies end in miscarriage. This generally happens early on, in the first three months. It's an emotional and difficult event for any person involved.

A miscarriage that occurs very soon after implantation, resulting in bleeding that occurs around the time of a woman's expected period, is called a chemical pregnancy. Many women who undergo chemical pregnancies don't realize they even conceived and miscarried. This often occurs around the fifth week of pregnancy, before anything can be seen on an ultrasound.

What causes miscarriages?

Miscarriages can be caused by a number of things, including invasive prenatal tests like chorionic villus sampling and amniocentesis. Many women tend to blame themselves for a miscarriage. But it's rarely the fault of the woman. The only behavioral risks that can increase miscarriage are smoking, heavy alcohol use, illicit drug abuse and heavy caffeine use. Nicotine can cross the placenta and interfere with blood supply and fetal growth rate, causing smokers to have twice the rate of miscarriage as nonsmokers. Drinking more than two alcoholic beverages a day is also linked to miscarriage. Contrary to what some believe, sex, exercise, medications, or minor trauma do not cause miscarriages.

However, severe trauma can increase the risk of miscarriages, as well as serious infections. The embryo or fetus may also have a chromosome that causes it to develop abnormally, leading to a miscarriage. This can include a blighted ovum, when no embryo develops; intrauterine fetal demise, when the embryo stops developing; or a molar pregnancy, a noncancerous tumor that develops in the fetus. This is not a sign of chromosomal problems in future pregnancies, however. It tends to happen by sheer chance at the point when the fertilized egg divides and continues to grow. This causes at least 60 percent of all miscarriages, according to the American College of Obstetricians and Gynecologists.

The condition of a woman's uterus and cervix play a large role in the development of the fetus. An abnormally shaped uterus, or uterine septum, can cause a miscarriage because the embryo can't implant or receive the nourishment it needs to survive. A weakened or incompetent cervix can't hold a fetus in, which can also lead to miscarriages, often later in the pregnancy.

Other risk factors for miscarriage include a woman's age and health — the older a woman is, the higher the risk of miscarriage. Severe chronic illnesses, like uncontrolled diabetes, immunologic diseases, or thyroid disease, can also increase the risk. A woman's weight also plays a role — underweight or overweight women are more likely to miscarry than other women. Those women who have had two or more miscarriages in a row may also be more prone to have future miscarriages.

Signs and symptoms

Common signs of a miscarriage include vaginal spotting or bleeding, dull lower backache or pressure, severe abdominal pain or cramping, and/or fluid or tissue being discharged from the vagina. These symptoms also apply to less serious conditions, but Planned Parenthood recommends consulting with your healthcare provider if you experience any of these symptoms. The Mayo Clinic recommends placing any discharged tissue in a clean container to your doctor for follow up tests.

Septic miscarriages can be caused by uterine infections. These have the added symptoms of fever, chills, lower abdominal tenderness, and a foul-smelling vaginal discharge.

Preventing miscarriage

Because miscarriage is often due to chromosomal abnormalities and outside of the woman's control, there aren't many ways to prevent it. The best that you can do is to keep your body as healthy as possible and limit any environmental factors, such as exposure to chemicals or radiation. It's important to eat healthy, keep at a healthy weight, exercise regularly, take folic acid, and live a healthy lifestyle without alcohol, cigarettes, or illicit drugs.

Chances of a miscarriage

Age plays a major factor in the chances of miscarriage. Women under the age of 35 have a 15 percent chance of miscarriage, while women between 35 and 45 have a 20 to 35 percent chance. Women past the age of 45 have a 50 percent chance of miscarriage. For women who have already had a miscarriage, they have a 25 percent chance of having another.

Treating miscarriage

After a miscarriage, the main goal of treatment is to avoid hemorrhaging and infections. The earlier in the pregnancy, the more likely it is that the woman will not need any further medical attention, as the body is likely to expel all of the fetal tissue on its own. If this does not happen, the doctor may need to perform a dilation and curettage, known as a D&C. Drugs may be prescribed to help with the bleeding, which needs to be monitored at home. The American Pregnancy Association recommends calling your healthcare provider if you notice any increases in bleeding or chills and fever.

It's also important to consider the mental toll that miscarriage can take on a person. Emotional recovery can be a long and difficult road. Keep lines of communication open with your loved ones, healthcare provider, and consider a support group or resources like MEND or A Place to Remember.

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