Miscarriage: Causes, Treatment and Next Steps

• What is Miscarriage (Early Pregnancy Loss)?
• Causes of Miscarriage
• Diagnosis Of Miscarriage
• Miscarriage Management and Treatment Options
• Miscarriage Support and Resources
• Planning Your Next Pregnancy 

What is Miscarriage (Early Pregnancy Loss)?

Imagine that you have been trying to get pregnant, and it finally happens. You’re thrilled and excited, until one day you notice slight cramping and a little bleeding. Is that normal? Are you going to miscarry? What happens next? Let’s explore the topic of miscarriage. Miscarriage is a commonly used term used to describe a condition in pregnancy called early pregnancy loss (EPL) or spontaneous abortion. For this article, we will use the term miscarriage, early pregnancy loss, and spontaneous abortion interchangeably.  Early pregnancy losses occur in the first trimester of pregnancy, within the first 12 weeks. First trimester loss is the most common type of miscarriage. It describes a pregnancy that has no chance of continuing.  Generally, 10% of women with a diagnosed pregnancy will miscarry, and of those, 80% will lose the pregnancy in the first trimester.

Causes of Miscarriage

• Genetically Abnormal Embryo
• Age
• Previous Miscarriage
• Toxin
• Certain Medical Conditions

Genetically Abnormal Embryo

Half of pregnancies lost in the first trimester are due to a chromosomal abnormality in the baby. For this reason, an evaluation is not done to determine the cause of loss if you are experiencing it for the first time. The diagnosis of a genetically abnormal pregnancy is presumed to be the cause.

Maternal Age

According to a 2006 Centers for Disease Control (CDC) report the risk of miscarriage increases with age. Between ages 20-30, your chance of miscarriage is anywhere from 9–17%. The risk of early pregnancy loss is 20% at age 35, 40% at age 40, and a whopping 80% at age 45. 
Study of over 420,000 women assessing risk of miscarriage by age.

 

Age (years)	Risk EPL Percent
Under 20	17
20-24	11
25-29	10
30-34	11
35-39	17
40-44	40
45+	80

As you age, the risk of chromosomal abnormalities increases. For example, the chance of experiencing a chromosomally abnormal pregnancy is:

• 1 in 650 at age 25
• 1 in 350 at age 35
• 1 in 39 at age 40
• 1 in 10 at age 49

This increase in fetal chromosome abnormalities is the main reason older women experience a higher rate of early pregnancy loss.

Previous Miscarriage

Having had a previous miscarriage puts you at a higher risk of experiencing another.

• In a first pregnancy, the risk of miscarriage is 11 to 13 percent.
• After one miscarriage, this rate rises slightly to 14 to 21 percent.
• After two miscarriages, the rate is 24 to 29 percent.
• After three miscarriages, the rate 31 to 33 percent.

If you have experienced three or more pregnancy losses, that is referred to as recurrent pregnancy loss. That is a condition that is discussed separately. However, if you have experienced at least one live birth, this will increase your chance of a successful pregnancy.

Medical Conditions

Any medical condition that negatively impacts your health has the potential to cause a miscarriage. Some of the more common conditions that increase the risk are:

• Certain infections: 15% of miscarriages are associated with an infection, particularly parvovirus B19, untreated syphilis, and cytomegalovirus (CMV).
• Diabetes: The effects of diabetes on early pregnancy can result in fetal anomalies or pregnancy loss. Maintaining tight control of glucose levels before and during pregnancy brings this risk back to baseline.
• Obesity: Obesity is even more strongly associated with pregnancy loss than diabetes. A 2008 analysis of 16 studies showed that a body mass index greater than 25 was associated with a nearly 70 percent increased odds of early pregnancy loss.
• Thyroid Disease: Both an underactive and an overactive thyroid is associated with an increase in early pregnancy loss.
• Stress: A short period of stress, such as a busy time at work, is unlikely to impact your pregnancy. However, long-term life stressors can increase the risk of early pregnancy loss.
• Getting Pregnant with an intrauterine device (IUD) in place: While IUDs are some of the most effective contraceptive methods, failures can occur. If you happen to become pregnant while having the IUD in place, you’re less likely to have a miscarriage if you remove the device.
• Substance Abuse: Tobacco, caffeine, and alcohol use increase the risk of pregnancy loss in a dose-related fashion. Some studies have reported increased risks with exposure to cocaine or methamphetamines. Marijuana use in pregnancy does not appear to increase the risk of pregnancy loss, although it does negatively impact fetal development.
• Exposure to Toxins and Pollutants: Exposure to X-rays, excessive lead, arsenic, and air pollution are all associated with early pregnancy loss.
• Race and Ethnicity: Studies have reported an increased risk of early pregnancy loss in women of color compared with white women. This difference is more likely due to social stressors and occupational or environmental exposure to toxins than a real biological difference.
• Subchorionic hematoma: Sometimes, when the placenta implants into the uterus, there can be bleeding. The blood accumulates in one area, called a hematoma, and can increase the risk of miscarriage.
• Medications: Three factors influence the risk of a medication causing miscarriage:
  • The drug
  • The dose
  • The timing of exposure- the stage of pregnancy in which you took the drug.

There is a sparsity of online databases of drugs in pregnancy. Some resources for information about the impact of specific drugs on pregnancy can be found at:

• Your physician-your physician is the most reliable resource for information specific to you and your pregnancy.
• National Institute of Health (NIH) Drug Information Portal
• US Food and Drug Administration (FDA) Pregnancy Registry
• Mothertobaby.org– a group of teratologist with information on drugs in pregnancy
• March of Dimes
• Prescribing Medicines in Pregnancy Database Australia

Diagnosis Of Miscarriage (Early Pregnancy Loss)

Early signs of a miscarriage, such as uterine cramping and vaginal bleeding, are symptoms that can also occur in a healthy pregnancy. These symptoms alone are not enough to make a definite diagnosis of a miscarriage. Additional testing is needed before treatment is started. Your provider will most likely perform:

• A careful history including the date of your last normal menstrual period, the duration and quantity of the bleeding, any pain experienced, and contraceptive use around the time of conception.
• A physical examination to estimate uterine size, document bleeding, and check if your cervix is open or closed.
• A blood pregnancy test that determines the amount of pregnancy hormone circulating in your body. This test can be repeated at specific intervals to determine if it is increasing normally.
• An ultrasound is a commonly used tool in evaluating early pregnancies. This determines the pregnancy location and if normal development is occurring. Just like the blood pregnancy hormone test, the ultrasound may be repeated over several days.

While it may be frustrating or inconvenient to have repeat testing, this is the best way for your doctor to be sure that a miscarriage is the correct diagnosis.

Miscarriage Management and Treatment Options

If the diagnosis of early pregnancy loss is confirmed, there are three treatment options:

• Expectant management- waiting and allowing pregnancy to progress naturally without any intervention.
• Medical therapy- taking medicines to encourage your body to pass the pregnancy.
• Surgical treatment- a surgical procedure to physically remove the pregnancy from the womb.

An early pregnancy loss that occurs in the first trimester may not require treatment. If you decide to wait, you have an 80% chance of passing your pregnancy within eight weeks. The bleeding can be heavier than a menses and accompanied by severe uterine cramping. If the bleeding becomes heavy, you will need to notify your doctor or seek emergency care.

Medication is another treatment option available for early pregnancy loss. It may be used only when there is no evidence of:

• infection
• heavy bleeding
• severe anemia
• bleeding disorders

The medication used is misoprostol, pron. me-so-pros-til, (also called Cytotec):

• It is given vaginally, and less commonly, orally.
• A second dose is required if there is no effect within seven days
• It decreases the length of time it takes to pass the pregnancy tissue (compared to waiting for natural passage).
• It causes the cervix to become soft and thin. The uterus cramps and contracts. The pregnancy then passes vaginally.

In the United States, the largest trial that studied the use of misoprostol for early pregnancy loss found that 71% of women completely passed their pregnancy by the third day after one dose of medication. This increased to 84% when a second dose was added. The occurrence of adverse events was rare, making it a safe treatment option.

Some women with early pregnancy loss prefer the option of surgical management because it provides a more immediate solution. The procedure is called suction dilation and curettage, or just D&C. A small thin tool is attached to a suction machine, and the uterine contents are gently emptied or curettage. Women who show signs of infection, are hemorrhaging, or who are unstable, require immediate surgery. Otherwise, the procedure is scheduled at your convenience.

SUMMARY

Many studies have demonstrated that expectant management (waiting), medical therapy, and surgical treatment of early pregnancy loss in most women will have similar success rates and minimal complications. Heavy bleeding and infection can occur with any of these treatment options. Still, the rates are similar and quite low. Bleeding that requires hospitalization occurs at the rate of 0.5-1%, and the rate of infection requiring antibiotic therapy was 1-2%. Women who want contraception may start the birth control pill or have an IUD placed immediately after early pregnancy loss. At this time, there are no effective methods to prevent miscarriage.

Support:

If you find that you are grieving the loss of your pregnancy, please know that this is normal, and you are not alone. Sharing your feelings with your partner, friends, or counselor may be helpful. You may find comfort in creating a keepsake to commemorate and honor your lost pregnancy.

Pregnancy Loss Support Resources:

• Share-Pregnancy and Infant Loss Support Center
• SAMHSA– Substance Abuse and Mental Health Services Administration

Planning Your Next Pregnancy:

After having a completed miscarriage, it is possible to become pregnant right away. If you do not wish to become pregnant, use contraception. If you desire to become pregnant, you may start trying right away. There is no need to delay conception after an early pregnancy loss. Waiting for at least one period will help to date your subsequent pregnancy.

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Written by: Lisa Ann Shephard, MD |Editor: Dayna Smith MD |Reviewed: June 30, 2020

Copyright: myObMD, 2020

Glossary:

• Embryo– conception within the first eight weeks after conception. This is when the baby is most vulnerable to toxins as organ formation takes place during this period.
• Fetus– time period between embryo and birth, the unborn child is referred to as a fetus.
• Chromosome– genetic material passed along at conception
• Ultrasound– device used to visualize inside they human body. Commonly used to visualize pelvic organs and developing babies.
• Cervix-the lower portion of the uterus that extends into the vagina.
• Parvovirus B19 (Parvo B19)– virus causing Fifth Disease in children. Pregnant women who are in close contact with school age toddlers and infants are most vulnerable. Able to cross the placenta and cause miscarriage in a developing fetus, usually through severe anemia.
• Cytomegalovirus (CMV)– virus common among most adults. Most vulnerable pregnant patients are those who become infected with CMV for the first time in pregnancy.
• Syphilis– sexually transmitted bacterial infection. Left untreated can cause stillbirth or death of newborn. All women receiving prenatal care in the US are receive a test for syphilis.
• Dilation & Curettage (D&C)– procedure used to empty the uterus of pregnancy tissue or used to biopsy the tissue that lines the uterus (endometrium).
• Curettage– action of removing tissue from the uterus during a D&C procedure
• Hemorrhage– excessive bleeding that can become life threatening
• Thyroid-gland that sits in the neck, between your chin and collar bone. It releases hormone that affects all parts of our body and helps to keep our body in hormonal balance.
• Intrauterine Device (IUD)– “T” shaped contraceptive device placed inside the uterus by your medical provider. Length of contraceptive benefit varies from 3 to 10 years.