Miscarriage is a term describing cases where a pregnancy terminates on its own, typically within the first 20 weeks of a normal gestational period.
According to the American College of Obstetricians and Gynecologists (ACOG), miscarriages are the most common type of pregnancy loss. A miscarriage occurs after a pregnancy is lost after implantation fails, which results in bleeding occurring around the time of a woman’s expected period. In many cases, women who experience this characteristic bleeding may have not suspected they were pregnant. Most miscarriages occur during the first 13 weeks of a pregnancy.
Studies have shown that as much as 10 to 25 percent of clinically recognized pregnancies end in miscarriage. Chemical pregnancies are said to potentially account for as much as 50 to 75 percent of all miscarriages.
Missed Miscarriage Statistics
1. As much as 1 percent of all pregnancies will result in a missed miscarriage.
2. At least 20 percent of pregnancies are likely to result in a miscarriage.
3. The overall risk of miscarriage is 17 to 22 percent.
4. The risk after the gestational sac develops is as much as 12 to 15 percent.
5. The risk of miscarriage is 9.4 percent after a heartbeat is detected at 6 weeks. The percentage drops to 4.2 percent at 7 weeks, 1.5 percent at 8 weeks and 0.5 percent at 9 weeks.
6. The risk of miscarriage increases 12 percent after age 30. It increases to as much as 39 percent after age 35 and doubles after age 40 (about 78 percent).
7. People with partners over 40 years old increases the risk of miscarriage by as much as 60 percent.
8. The risk of miscarriage increases by as much as 43 percent with partners of age 35. The risk increases to as much as 90 percent with partners at age 50.
9. The risk of miscarriage increases to 88 percent when the father is over 50 years old.
10. The risk of miscarriage doubles for people who need more than 1 year to have a successful conception.
Why Miscarriages Occur
Miscarriages happen for various reasons. In most cases, there’s no true cause behind a miscarriage. Miscarriages do, however, occur in the first and second trimester of pregnancy. While miscarriages rarely occur during the third trimesters, they’re often referred to as still births instead.
The most common cause of miscarriage in the first trimester usually is a chromosomal abnormality, meaning that something is wrong with the fetus’ chromosomal make up. Most of these abnormalities are caused by a damaged sperm or egg cell or an issue occurring at the time of the zygote’s cell division process.
Other reasons for miscarriages include the following:
1. Hormonal problems or infections.
2. Maternal health problems.
3. Lifestyle-related issues, including smoking, drug use, excessive caffeine, malnutrition and, in rare cases, exposure to radiation or other toxic substances.
4. Maternal age or trauma.
5. Failed implantation of the egg into the uterine lining.
Several factors are said to not cause miscarriage, which include (and aren’t limited to) sexual intercourse, moderate exercise and working outside the home.
Risks of Having a Miscarriage
The chances of women having a miscarriage in their childbearing years range from as low as 10 percent to as high as 25 percent. For most healthy women, it averages to around a 15 to 20 percent chance.
1. Older women have an increased chance of having a miscarriage.
2. Women under age 35 have a 15 percent chance of having a miscarriage.
3. Women between the ages of 35 to 45 years old have as much as a 50 percent chance of miscarriage.
4. Women who have experienced a past miscarriage have a 25 percent chance of having another, a slightly elevated risk in comparison to women who haven’t had one.
Warning Signs of a Miscarriage
Miscarriages have several associated symptoms. Women who experience any of these symptoms are advised to immediately contact their health care provider and/or a medical facility to determine whether they’re having a miscarriage or not.
The symptoms of a miscarriage include the following:
1. Mild to severe back pain.
2. Weight loss.
3. True contractions, which are painful and occur every 5 to 20 minutes.
4. White-pink mucus.
5. Brown or bright red bleeding, sometimes with cramps.
6. Tissue with clot-like material expelled from the vagina.
7. Sudden decrease in any pregnancy signs.
Although miscarriages have many of the same symptoms, many different stages or types of miscarriage exist.
Types of Miscarriage
Most types of miscarriage are simply referred to as a miscarriage. Health care providers, including doctors, do refer to miscarriage under different terminology than what most women hear.
Threatened miscarriage: Some early pregnancy uterine bleeding accompanied by cramping or other backaches. The bleeding typically occurs due to implantation, though the cervix remains closed.
Incomplete miscarriage: Typically involves abdominal or back pain accompanied by bleeding, while the cervix remains open. This miscarriage happens when dilation or effacement and/or ruptured membranes are present. Both cramps and bleeding may continue if the miscarriage isn’t complete.
Complete miscarriage: Occurs when the products of conception or embryo empty from the uterus. Bleeding often subsides quickly, in addition to any cramping or pain. Completed miscarriages are often confirmed by ultrasound or a surgical curettage.
Missed miscarriage: Occurs when embryonic death occurs without any expulsion of the embryo itself. There’s no known cause behind this type of miscarriage. The signs typically include a loss of pregnancy symptoms and a lack of fetal heart tones on an ultrasound.
Many types of miscarriages are explored in educational materials. In the rest of this article, we’re going to take a closer look at missed miscarriages and their statistics.
Missed Miscarriages
A missed miscarriage occurs when the fetus dies and the body doesn’t recognize the loss of pregnancy and/or doesn’t expel the pregnancy tissue. Due to this, the placenta might continue to release hormones, causing women to still experience signs of pregnancy.
This type of miscarriage is typically diagnosed during routine checkups, when doctors generally fail to detect a discernible heartbeat. If an ultrasound is conducted, the ultrasound may reveal an underdeveloped fetus.
Signs of Missed Miscarriages
Women who have missed miscarriages generally don’t experience any miscarriage symptoms, including heavy cramping, vaginal bleeding or fecal tissue expulsion. This is due to the placenta releasing pregnancy hormones, which play a role in continuing pregnancy symptoms for women.
Some women, however, do experience diminishing pregnancy symptoms if they’re experiencing a missed miscarriage. Others also may have red or brownish vaginal discharge. Doctors generally diagnose missed miscarriages when they detect no fetal heartbeat and/or when an ultrasound, as mentioned, shows an underdeveloped fetus.
Causes and Treatment of Missed Miscarriages
In most cases, a missed miscarriage is caused by a chromosomal abnormality in the fetus. The presence of such an abnormality causes the pregnancy to stall and eventually fail to develop. Most treatments for missed miscarriages involve helping the patient safely expel their pregnancy tissue.
If the tissue remains within the body for a longer amount of time, a surgical curettage is typically performed to safely remove the remainder of the tissue. The procedure itself opens the cervix while the fetal tissue is removed. This helps eliminate the possibility of an infection developing, which may happen if any of the fetal tissue remains within the body.
Couples are encouraged to wait between one to three menstrual cycles before attempting to conceive again.