Miscarriage is the medical term that describes a pregnancy that ends on its own, within the first 20 weeks of gestation. Pregnancy occurs in three trimesters: the first 12 weeks of a pregnancy are the first trimester, weeks 13 to 27 are the second trimester and the remainder of the pregnancy makes up the third trimester. Most miscarriages occur in the first trimester of pregnancy. Second trimester miscarriages can occur as well.
Miscarriage is the most common type of pregnancy loss. According to the March of Dimes, “about 10 to 15 out of 100 pregnancies end in miscarriage.” The organization reports “as many as half of all pregnancies may end in miscarriage.” In these pregnancies, known as chemical pregnancies, the miscarriage occurs shortly after implantation of the fertilized egg, resulting in bleeding that occurs around the time of expected menstruation. For this reason, women may not even realize they have miscarried.
During the first trimester, the most common cause of miscarriage is chromosomal abnormality within the zygote, which is the fertilized egg. Most chromosomal abnormalities are caused by a damaged egg or sperm cell or by a problem that occurs when the zygote undergoes cell division.
Other causes of miscarriage include maternal hormonal problems, infections or health issues; maternal lifestyle choices such as smoking, drug use, malnutrition and exposure to radiation or toxic substances; improper implantation of the fertilized egg into the uterine lining; maternal age; and maternal trauma, especially to the abdomen.
There are several different types of miscarriage, although most people use “miscarriage” as a blanket term to describe all of these varying conditions.
A threatened miscarriage is when there is some degree of uterine bleeding during early pregnancy, usually resulting from implantation of the fertilized egg, accompanied by cramping or lower back pain. The cervix remains closed in a threatened miscarriage.
In an inevitable or incomplete miscarriage, the woman experiences abdominal or back pain accompanied by bleeding with an open cervix. Miscarriage is inevitable whenever the cervix is dilated and/or the membranes rupture. Bleeding and cramps may persist if the miscarriage is incomplete.
A complete miscarriage is when the embryo has emptied out of the uterus. As a result, any bleeding and pain or cramping should subside quickly. A completed miscarriage can be confirmed by an ultrasound or by having a surgical dilation and curettage, also known as a D&C, to remove tissue from the inside of the uterus.
A missed miscarriage is when embryonic death occurs without expulsion of the embryo. Loss of pregnancy symptoms and the absence of fetal heart tones on an ultrasound are signs of a missed miscarriage. Women who experience a missed miscarriage often do not know they have miscarried.
Recurrent miscarriage is when a woman experiences three or more spontaneous consecutive first trimester miscarriages with the same biological father. According to the American Academy of Family Physicians, one to two percent of women experience recurrent miscarriage.
There are three other medical conditions that fall under the miscarriage category: blighted ovum, ectopic pregnancy and molar pregnancy.
A blighted ovum, also known as an embryonic pregnancy, is when a fertilized egg implants into the uterine wall without fetal development occurring. Often there is the presence of a gestational sac, with or without a yolk sac.
An ectopic pregnancy is when a fertilized egg implants itself in places other than the uterus, most commonly in a fallopian tube. Immediate treatment is required to stop the development of the implanted egg because an ectopic pregnancy can be life-threatening for the mother.
A molar pregnancy results from a genetic error during the fertilization process that leads to growth of abnormal tissue within the uterus. Molar pregnancies rarely involve a developing embryo despite being accompanied by the most common signs of pregnancy including a missed period, a positive pregnancy test and severe nausea.
According to the Mayo Clinic, women over the age of 35 have a higher risk of miscarriage than younger women. At age 35, the risk of miscarriage is 20 percent. At age 40, that risk rises to 40 percent. At age 45 and older, the risk rate for miscarriage is 80 percent. There are no conclusive studies on how paternal age affects miscarriage risks.
In addition, Mayo Clinic reports that miscarriage risk increases for women who have had two or more consecutive miscarriages, for women with chronic health conditions, such as diabetes, and for women who are underweight and who are overweight.
Symptoms of a miscarriage include mild to severe back pain, weight loss, white-pink mucous present in vaginal discharge, true contractions occurring every 5 to 20 minutes, brown or bright red bleeding with or without cramps, tissue with clot-like material passing from the vagina and sudden decrease in signs or symptoms of pregnancy.
For women experiencing any of the above symptoms, it is important to seek immediate medical treatment as miscarriages can cause hemorrhaging and/or infections.
The earlier the miscarriage occurs during pregnancy, the more likely the body will naturally expel all the fetal tissue by itself. If not, the most common procedure performed to stop bleeding and prevent infection is a brief surgical procedure called a D&C, or dilation and curettage, in which the cervix is dilated and a special instrument is used to scrape the uterine lining to remove any remaining fetal tissue.
Medications to help control pain and bleeding are often prescribed after a D&C is performed. Bleeding can be monitored at home. If there is an increase in bleeding or an onset of fever or chills, emergency medical care is advisable.
Since most miscarriages result from chromosomal abnormalities, there is really no way to prevent miscarriages from occurring.
It is important to understand that miscarriage affects every woman differently. Some women may worry about what will happen if and when they conceive again. Some women may require counseling for their emotional and mental health after experiencing a miscarriage. Communication is vital in the recovery process. Women need to feel that they can be honest with their friends, family and medical health professionals as they recover physically, emotionally and mentally from having had a miscarriage.
Being supportive without being judgmental is one of the best gifts we can give others in their times of need.