Stress and Miscarriage
Miscarriages are extremely common and occur in as many as 15 percent of confirmed pregnancies. This doesn’t include the pregnancies that end in miscarriage before woman knows she is pregnant. In such cases, the miscarriage rate can be as high as 40 percent. Most of the time, miscarriages happen due to things that are out of the woman’s control, such as chromosomal problems in the fetus and chronic medical conditions.
Stress, while many people believe can cause a miscarriage, has not been scientifically proven to result in miscarriage. It is difficult to do these kinds of studies as stress is difficult to measure and there are many, more common causes of miscarriages besides stress.
Chromosomal Abnormalities
While stress is not considered a major cause of miscarriages, chromosomal abnormalities in the fetus is the number one cause of miscarriages in the first and second trimester of pregnancy. Chromosomal abnormalities cause as many as 70 percent of miscarriages in the first trimester and 20 percent of miscarriages in the second trimester.
Chromosomal abnormalities occur when, in the process of fertilizing the egg, the resultant embryo has a missing chromosome or an extra chromosome. Only trisomy 21 (Down syndrome) is a survivable chromosomal abnormality in children, although the rate of miscarriage in Down syndrome is higher than is seen in babies who have normal chromosomes. Rarely, babies with trisomy 18 survive; most of them are lost in the first or second trimester and have significant birth defects.
Chromosomal abnormalities can be recurrent if there is an inherent chromosomal problem in the mother or the father, but most are just incidental and won’t reoccur in subsequent pregnancies. The rate of chromosomal abnormalities increases with both maternal and paternal age.
Chronic Medical Illnesses
The mother can have certain chronic conditions that lead to physical stress on the body and an increase in the rate of miscarriages. Diseases that limit the blood flow to the uterus will increase the chances that a woman will miscarry the pregnancy. In such cases, the infant may be normal but dies due to a lack of oxygenation inside the uterus. Common chronic diseases linked to miscarriage include thyroid disease, heart disease, uterine infections, lupus, and diabetes. Fortunately, these conditions don’t have to result in an increased risk of miscarriage if they are properly treated before the woman becomes pregnant.
Problems with Hormones
In some instances, the woman’s ovaries don’t make enough progesterone in the early part of pregnancy. Certainly stress can be a cause of this type of ovarian failure but this hasn’t been scientifically proven. The fetus needs high progesterone levels in order to be supported in early pregnancy before the placenta takes over and makes its own supporting hormones. Progesterone deficiency is not a common problem and is only usually tested for if the woman has had more than 2 miscarriages in a row. Fortunately, this cause of miscarriages can be managed with progesterone replacement in early pregnancy.
Other Factors causing a Miscarriage
Women who drink in excess of 200 milligrams of caffeine per day (the amount in about 5 sodas or 2 coffees) have twice the chance of having a miscarriage when compared to women who didn’t take in any caffeine. This was proven in a research study performed by Kaiser Permanente and published in the American Journal of Obstetrics and Gynecology. Caffeine intake is indirectly related to physical stress on the symptom which would be a link between stress and miscarriages.
No one knows why caffeine causes miscarriages. It is known that caffeine crosses the placental barrier, which means that it has the potential to affect the cells developing in the fetus. Experts recommend decreasing the caffeine intake in early pregnancy to a cup of coffee or less per day in order to decrease the chances of having a miscarriage. Decaffeinated coffee is perfectly acceptable to use in pregnancy and hasn’t been linked to excessive numbers of miscarriages.
Excess Cigarette, Alcohol, and Illicit Drug Use
Stress can lead a woman to drink too much, smoke cigarettes, or use illicit drugs during the first trimester of pregnancy, indirectly linking stress to the risk of miscarriages. There is scientific evidence that consuming alcohol, using illicit drugs, and excessive smoking exposes the fetus to toxins that can ultimately result in a miscarriage.
What doesn’t cause miscarriages?
Even though miscarriages are extremely common, there are a lot of myths around what causes miscarriages and what doesn’t. Misinformation is abundant as it is often passed down through the generations and certain things believed to cause miscarriages are nothing more than folklore.
For example, 20 percent of women believe that exercise can cause a miscarriage. Unfortunately, this hasn’t held up in scientific studies. In fact, exercise may actually lower the rate of miscarriage and can help the mother and fetus deal with the excess stresses seen in the early part of pregnancy. Exercise can also decrease the risk of gestational diabetes and can help a woman become more fit to tolerate the rigors of labor.
Greater than 35 percent of women believe that mood plays a role in getting miscarriages. During the first trimester, it is not uncommon to be depressed, anxious, and stressed out. Approximately 10-20 percent of women have depression at some point in the pregnancy but this hasn’t definitively been linked to having a miscarriage.
More than 75 percent of women believe that stress causes miscarriages. The truth is that some studies indicate a link between stress and miscarriage, while other studies indicate no such link. The regular stressors of one’s daily life hasn’t been connected to an increased risk of miscarriages in any way. Certainly stress can lead to poor lifestyle choices that secondarily increase the risk of miscarriage but stress alone is probably not a major cause of miscarriages.
Some women believe that certain behaviors on the part of the mother cause the majority of miscarriages. While behaviors like excessive cigarette use, illicit drug use, and alcohol use have been linked to an increased rate of miscarriages, most behaviors on the part of the mother do not increase the miscarriage rate. When thinking of miscarriage, one should think more along the lines of chromosomal abnormalities and less on the woman’s behaviors during the first few weeks of pregnancy.
References:
- Can too much stress cause a miscarriage? http://www.mayoclinic.org/healthy-lifestyle/pregnancy-week-by-week/expert-answers/early-miscarriage/faq-20058214.
- What does and doesn’t cause a miscarriage. http://www.parents.com/pregnancy/complications/miscarriage/causes-miscarriage/.