For most women, miscarriage is the biggest fear associated with pregnancy. Since the risk of miscarriage is highest in the first three months, many new parents choose to wait until after the first trimester to share the news with family or friends. However, just because miscarriages are most common in the first trimester, doesn't mean they're impossible in the second trimester as well. Here’s a look at the risks and causes of a second trimester miscarriage, as well as what happens afterwards.
What’s the risk of miscarriage in the second trimester?
By the twelfth week, or the beginning of the second trimester, the risk of miscarriage drops to about 10% -- less than 5% of pregnancies are lost after the thirteenth week. By the twentieth week, the risk of a loss of pregnancy, or stillbirth at this point, drops to less than 1%. However, it’s important to realize that women who've experienced miscarriage or stillbirth in the past, or have other complications associated with their pregnancy (such as being over age 35), may have higher risks. If you have any concerns, it’s important to talk to your doctor.
What can cause a miscarriage in the second trimester?
Contrary to an early miscarriage, where the cause isn’t generally known, most later term miscarriages have a more specific reason. In the second trimester, fetal loss may be related to fetal chromosomal atypical ties, maternal uterine atypical ties, an incompetent cervix, placenta previa or placental abruption, infections or illness of mother or fetus, or severe trauma (such as a car accident).
Unfortunately, in most cases, it’s very difficult, if not impossible, for doctors to stop the loss. Additionally, a fetus isn’t typically viable (able to survive outside the womb) until at least 23 weeks, and even then less than a third survive.
What happens when a miscarriage starts in the second trimester?
Like an early miscarriage, a second trimester pregnancy loss usually starts with cramping and/or vaginal bleeding. Although it depends on the risk to the mother, most losses at this point must be delivered vaginally; some will require a procedure known as a 'D&C' (dilation and curettage) to remove the uterus. Even if the loss occurs at home, mothers should seek immediate medical attention to make sure no products of pregnancy (such as the placenta) remain in the uterus. Mothers may also want or need pain relief.
What happens afterwards?
Most experts agree that because miscarriage during the second trimester is so rare, when there’s no obvious reason for the loss (such as trauma or infection), it’s often a good idea to have certain chromosomal or other tests run on the fetal remains. This information can be extremely important for parents who choose to try for another pregnancy. Depending on the underlying reason, it might not be possible or wise to attempt pregnancy again, but many women do go on to have healthy and successful future pregnancies.
As well as seeking medical help for anatomical treatment, it can also be important to look into psychological help. Some women have a much more difficult time with a miscarriage when it occurs later in the pregnancy. Furthermore, women who experience a second trimester loss are generally classified as high-risk for future pregnancies. This might mean seeing an obstetrician who specializes in high-risk pregnancies.
