What Are Some Risk Factors for Miscarriage and Pregnancy Loss?

Question: What Are Some Risk Factors for Miscarriage and Pregnancy Loss?


A lot of people wonder about risk factors for miscarriages. The truth is that risk factors are a complicated subject. A lot of women who miscarry will have no risk factors beforehand, and others might have every possible risk factor for pregnancy loss but still end up with a normal pregnancy. Except for avoiding known lifestyle factors that increase miscarriage risks, usually you cannot do much to affect the outcome of your pregnancy.

Let’s differentiate miscarriage risk factors from miscarriage symptoms, because the distinction might be confusing. After all, a person with symptoms of miscarriage is at risk for a miscarriage too, since most symptoms are not definitive. For the purposes of this article, we’ll consider miscarriage symptoms to be factors in an existing pregnancy that might indicate a miscarriage is already happening. We’ll use the term risk factors to indicate factors present before and during pregnancy that might be correlated with higher odds of a future miscarriage.

Again, remember that not everyone who has risk factors for pregnancy loss will miscarry and also that a person can miscarry even in the absence of any known risk factors. Also, in most cases, even a person with increased risk of miscarriage is more likely to have a normal pregnancy than to miscarry.

Medical Conditions Correlated with Increased Miscarriage Risk

Most miscarriages are the result of random chromosomal abnormalities, and the risk for conceiving a baby with chromosomal abnormalities is higher as the mother gets older.

In other cases, certain medical conditions in the mother might mean a greater than average risk of pregnancy loss, stillbirth, or recurrent miscarriages.

  • Mother’s age (younger than 15 or older than 35)
  • Problems in earlier pregnancies
  • Conceiving after infertility
  • Being very overweight or underweight

The risk for conceiving a baby with chromosomal abnormalities is higher as the mother gets older.

Lifestyle Factors Correlated with Increased Miscarriage Risk

Sometimes certain lifestyle factors might increase an individual person’s risk of pregnancy loss as well. These factors on their own usually do not cause miscarriages, given that many people who have these lifestyle factors do not miscarry, but these factors do increase risk of pregnancy loss.

Factors Possibly Correlated with Increased Miscarriage Risk

With research constantly ongoing, some factors may or may not be associated with greater miscarriage risk. Sometimes one study indicates a risk while another study does not.

The following factors fall into that category, and the medical community is still debating whether a link exists between the following factors and pregnancy loss.

Factors Not Associated with Increased Miscarriage Risk

No discussion of miscarriage risk factors would be complete without addressing some of the myths and misconceptions out there about what can cause a pregnancy loss. The following factors have not been shown to cause miscarriages for the majority of women, although you should follow your doctor’s recommendations for your own health.


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