Miscarriage

The medical name for miscarriage is spontaneous abortion (SAB) and in this this article we will refer to any type of spontaneous abortion or pregnancy loss under 20 weeks as miscarriage.

Miscarriage is the most common type of pregnancy loss, and studies reveal that anywhere from 10-25% of all clinically recognized pregnancies will end in miscarriage.

Chemical pregnancy, a pregnancy with a positive pregnancy test but no visible pregnancy on ultrasound, may account for 50-75% of all miscarriages. A chemical pregnancy occurs when a pregnancy is lost shortly after implantation, resulting in bleeding that occurs around the time of or shortly after her expected period. Unless there was a positive pregnancy test the woman may not realize that she conceived when she experiences a chemical pregnancy.

Most miscarriages occur during the first trimester or 12-13 weeks of pregnancy. There can be many confusing terms and moments that accompany a miscarriage, as well as different types of miscarriage, different treatments for each, and different statistics for what your chances are of having one.

The following information gives a broad overview of miscarriage. This information is provided to help you understand what is going on in the body during a miscarriage and be better equipped to cope with the situation. As with most pregnancy complications, remember that the best person you can usually talk to and ask questions of is your health care provider.

Causes of Miscarriages
The reason for miscarriage is varied, and most often the cause cannot be identified. During the first trimester, the most common cause of miscarriage is chromosomal abnormality - meaning that something is not correct with the baby's chromosomes. Most chromosomal abnormalities are the cause of a faulty egg or sperm cell, or are due to a problem at the time that the zygote went through the division process.

Causes for miscarriage include (but are not limited to):

• Chromosomal anomalies
• Hormonal problems, infections or maternal health problems
• Lifestyle (i.e. smoking, drug use, malnutrition, excessive caffeine and exposure to radiation or toxic substances)
• Implantation of the egg into the uterine lining does not occur properly
• Maternal age
• Maternal trauma

Factors that are not proven to cause miscarriage are sex, working outside the home (unless in a harmful environment) or moderate exercise.

What are the Chances of Having a Miscarriage?
For women in childbearing years, the chances of having a miscarriage can range from 10-25%, and in most healthy women the average is about a 15-20% chance.

• An increase in maternal age affects the chances of miscarriage
• Women under the age of 35 yrs old have about a 15% chance of miscarriage
• Women who are 35-45 yrs old have a 20-35% chance of miscarriage
• Women over the age of 45 can have up to a 50% chance of miscarriage
• A woman who has had a previous miscarriage has a 25% chance of having another (only a slightly elevated risk than for someone who has not had a previous miscarriage)

What are the Warning Signs of Miscarriage:
If you experience any or all of these symptoms, it is important to contact your doctor or a medical facility to evaluate if you could be having a miscarriage:

• Mild to severe back pain (often worse than normal menstrual cramps)
• Weight loss
• White-pink mucus
• True contractions (very painful happening every 5-20 minutes)
• Brown or bright red bleeding with or without cramps (20-30% of all pregnancies can experience some bleeding in early pregnancy, with about 50% of those resulting in normal pregnancies)
• Tissue with clot like material passing from the vagina
• Sudden decrease in signs of pregnancy

The Different Types of Miscarriage:
Miscarriage is often a process and not a single event. There are many different stages or types of miscarriage. There is also a lot of information to learn about healthy fetal development so that you might get a better idea of what is going on with your pregnancy. Understanding early fetal development and first trimester development can help you to know what things your health care provider is looking for when there is a possible miscarriage occurring.

Most of the time all types of miscarriage are just called miscarriage, but you may hear your health care provider refer to other terms or names of miscarriage such as:

• Threatened Miscarriage: Some degree of early pregnancy uterine bleeding accompanied by cramping or lower backache. The cervix remains closed. This bleeding is often the result of implantation.
• Inevitable or Incomplete Miscarriage: Abdominal or back pain accompanied by bleeding with an open cervix. Miscarriage is inevitable when there is a dilation or effacement of the cervix and/or there is rupture of the membranes. Bleeding and cramps may persist if the miscarriage is not complete.
• Complete Miscarriage: A completed miscarriage is when the embryo or products of conception have emptied out of the uterus. Bleeding should subside quickly, as should any pain or cramping. A completed miscarriage can be confirmed by an ultrasound or by having a surgical curettage performed.
• Missed Miscarriage: Women can experience a miscarriage without knowing it. A missed miscarriage is when embryonic death has occurred but there is not any expulsion of the embryo. It is not known why this occurs. Signs of this would be a loss of pregnancy symptoms and the absence of fetal heart tones found on an ultrasound.
• Recurrent Miscarriage (RM): Defined as 3 or more consecutive first trimester miscarriages. This can affect 1% of couples trying to conceive.
• Blighted Ovum: Also called an anembryonic pregnancy. A fertilized egg implants into the uterine wall, but fetal development never begins. Often there is a gestational sac with or without a yolk sac, but there is an absence of fetal growth.
• Ectopic Pregnancy: A fertilized egg implants itself in places other than the uterus, most commonly the fallopian tube. Treatment is needed immediately to stop the development of the implanted egg. If not treated rapidly, this could end in serious maternal complications.
• Molar Pregnancy: The result of a genetic error during the fertilization process that leads to growth of abnormal tissue within the uterus. Molar pregnancies rarely involve a developing embryo, but often entail the most common symptoms of pregnancy including a missed period, positive pregnancy test and severe nausea.

Treatment of Miscarriage:
The main goal of treatment during or after a miscarriage is to prevent hemorrhaging and/or infection. The earlier you are in the pregnancy, the more likely that your body will expel all the fetal tissue by itself and will not require further medical procedures. If the body does not expel all the tissue, the most common procedure performed to stop bleeding and prevent infection is a dilation and curettage, known as a D&C. Drugs may be prescribed to help control bleeding after the D&C is performed. Bleeding should be monitored closely once you are at home; if you notice an increase in bleeding or the onset of chills or fever, it is best to call your physician immediately.

Prevention of Miscarriage:
Since the cause of most miscarriages is due to chromosomal abnormalities, there is not much that can be done to prevent them. One vital step is to get as healthy as you can before conceiving to provide a healthy atmosphere for conception to occur.

• Exercise regularly
• Eat healthy
• Manage stress
• Keep weight within healthy limits
• Take folic acid daily
• Do not smoke

Once you find out that you are pregnant, again the goal is to be as healthy as possible, to provide a healthy environment for your baby to grow in:

• Keep your abdomen safe
• Do not smoke or be around smoke
• Do not drink alcohol
• Check with your doctor before taking any over-the-counter medications
• Limit or eliminate caffeine
• Avoid environmental hazards such as radiation, infectious disease and x-rays
• Avoid contact sports or activities that have risk of injury

What are My Chances of Having a Miscarriage Under the Following Situations?:

• The chance that you would miscarry after 7 weeks having a positive fetal heart rate is low, likely below 5-10%.
• At 7 weeks and with a fetal heart rate above 100 beats per minute (bpm), the chance of a miscarriage would probably be around 10-15%, though the exact number also depends on the woman's age.
• With every week your pregnancy progresses, your chance for a miscarriage continues to fall.

Miscarriage-Risk Rates:
Here are the odds of a miscarriage based on pregnancy age

• Chemical pregnancy (positive HCG test, no missed period): 50+%
• Missed period: 25%
• Around 7 weeks after last period with positive fetal heart beat above 100 bpm: 10-15%
• 10 weeks after last period: 5%