Your Pregnancy Matters
Stillbirth: What we know (and don’t know) about pregnancy loss
October 16, 2018
Experts estimate that, worldwide, approximately 2.6 million pregnancies ended in stillbirth in 2015. Stillbirth is the loss of a baby before birth, though pregnancy loss before 20 weeks is usually referred to as miscarriage.
Stillbirth occurs in 1 in 200 pregnancies – it’s more common than many women think, likely because it is a difficult topic for women to discuss. The cause of stillbirth is often unexplainable, and it leaves a lasting effect on patients and providers. Women and their doctors might be left wondering what they could have done differently to prevent the tragedy.
Because of the significance, a great deal of time, effort, and money has been spent investigating ways to decrease the frequency of stillbirth. While there is still much to learn, we know that the traditional preventive technique of “kick counts” is ineffective and that certain conditions or problems can increase the risk of stillbirth.
Can stillbirth be prevented?
In the past, doctors would routinely recommend “kick counts” to help women feel confident in their babies’ health leading up to delivery. We would tell women to sit quietly twice a day and count the number of times their babies moved. At least 10 times in two hours is considered by many to be a normal amount of fetal movement.
However, not all women feel movements the same way, leading to inaccurate count data. Also, a woman’s ability to notice fetal movements goes down as she gets closer to her due date – it’s estimated that moms feel only about 15 percent of their babies’ movements the last month of pregnancy. This phenomenon is due, perhaps, to decreased room in the womb causing more subtle movements, which are less noticeable to the mother.
Because kick counts vary from one woman to another, doctors have tried to encourage women to present for evaluation when the baby is moving less than usual. Data from a large trial called Awareness of Fetal Movements and Care Package to Reduce Fetal Mortality (AFFIRM) examined this practice. The results were published in September 2018. AFFIRM researchers found that, even with use of extra sonograms and other studies for women with decreased fetal movement, there was no change in the rate of stillbirth. However, doctors were more likely to induce labor and perform a cesarean section, which is not a good thing.
What are the known causes of stillbirth?
Known risk factors for stillbirth can be grouped into three categories – those involving the baby, placenta, and mother.
Fetal risk factors
Fetuses with birth defects or a genetic disorder often are at increased risk of stillbirth. This is one of the reasons we offer genetic screening along with sonographic evaluation of your baby’s anatomy. If your doctor finds an issue or disorder, we might change how we manage your pregnancy.
Multiple gestations (twins, triplets, or more) are at increased risk of stillbirth, as are fetuses that were conceived with the help of fertility treatments. For this reason, current recommendations are usually for transfer of only one egg during in vitro fertilization to decrease the risk of multiples.
Placental risk factors
Sometimes the placenta does not form and function correctly, which can lead to poor fetal growth and, eventually, a stillbirth. Providers track fetal growth through measurement of fundal height (measuring the woman’s abdomen with a tape measure) and ultrasounds (if the fundal measurement is abnormal) to attempt to prevent fetal complications or stillbirth.
Maternal risk factors
Stillbirths often occur in women with high-risk conditions, such as obesity, tobacco use during pregnancy, high blood pressure (preeclampsia), and diabetes. The risk is highest when these conditions are not well-managed. Women with such conditions might require more frequent prenatal visits, additional testing, admission to the hospital during pregnancy, or even early delivery to reduce the risk of maternal or fetal complications.
A few closing thoughts
Most stillbirths occur at or near a woman’s due date, and many are sudden and unexpected. Today, there is no known way to completely eliminate a woman’s risk of stillbirth. However, if you are a healthy woman with a normal sonogram and genetic screening, and you attend all of your prenatal appointments, the risk is very low. If you have a medical condition such as high blood pressure or diabetes, you can decrease the risk by working with your doctor to ensure your disease is well-controlled.
Stillbirth is tragic, and we continue to advance research into ways to further assess risk and reduce these life-altering events. If you experience stillbirth, resources are available to help you find strength and cope with your loss.