Stillbirth Risk Factors
Stillbirth, according to the National Stillbirth Society, is defined as the intrauterine death and subsequent delivery of a developing infant that occurs beyond 20 completed weeks of gestation. Prior to 20 weeks, a pregnancy loss is referred to as miscarriage. Stillbirth occurs in one in 160 pregnancies with the majority of them happening before labor starts. A small percentage of stillbirths occur during labor and delivery.
A lost pregnancy is a difficult experience for a couple and stillbirth seems to be such a cruel outcome. The parents are dealing with the issue of death and loss when it should have been a time of joy and life. The emotional trauma a stillbirth brings is difficult to define and couples often require help getting through the event.
The obvious questions are Why? and How? Sometimes there is a reason and often there isn't. However, knowing the risk factors for stillbirth can help a couple be on guard for the health of the mother and baby. Today, factors that would have been fatal in the past can be diverted and addressed, and the baby can be saved. There are common risk factors for stillbirth, which we will discuss in this article.
Stillbirth Risk Factor: Race and Socioeconomic Factors
In the United States, black women have twice the risk of stillbirth when compared to white women. Some of this has to do with socioeconomic factors such as lower income, lack of adequate prenatal care, lower education and the likelihood of having received publicly funded prenatal care. In one study, black mothers who had a stillbirth were less likely to have sought obstetric care in the first three months of pregnancy.
However, even when the socioeconomic factor was not an issue and black women had received adequate prenatal care, it was found that in the US black women still had twice the risk of stillbirth when compared to white women. The reasons according to one study (Vintzileos et al) were:
· higher rates of diabetes
· placental abruption
· premature rupture of membranes
Effective, early, frequent prenatal care can be influential in dealing with such high-risk pregnancies.
Stillbirth Risk Factor: Advanced Maternal Age
Women who are over the age of 35 still account for the majority of stillbirths, considering they are at greater risk for medical conditions that are problematic to pregnancy and associated with stillbirth:
· multiple gestation
· previous abortion
· placenta abruption
A woman over the age of 35 should ensure she is receiving adequate monitoring and prenatal care.
Stillbirth Risk Factor: Obesity
Obesity is an ever-growing problem in the United States, with numbers rising consistently. Poor diet, lack of exercise, and health issues that are not addressed properly are all contributors to this problem. The prevalence of obese mothers is closely associated with the increase risk of macrosomia and stillbirth. Macrosomia is the condition of a newborn with excessive birth weight of greater than 90% for gestational age, after adjusting for sex and ethnicity. Male babies tend to be bigger than female babies and some ethnic groups tend to be bigger or smaller than others.
The reasons for the association between obese mothers and excessive birth weight babies are thought to be due to three factors:
· behavior (diet and exercise, lifestyle)
· obstetric factors
Obese women are more likely to smoke and their pregnancies are more likely to be complicated with gestational diabetes and preeclampsia (toxemia). Yet, even when these factors are controlled, the raised BMI of obese women is a significant risk factor in stillbirth. One aspect of obesity that is a serious concern is the amount of time obese women spend snoring when they sleep. Obese women have more apnea-hypoxia events (occasions when breathing stops for a period of time and then resumes) and more periods of oxygen desaturation (lack of oxygen) than pregnant women who are not obese. Snoring has also been linked to pregnancy-induced hypertension and fetal growth restriction.
Stillbirth Risk Factor: Infertility Treatments
Often, when a woman decides to delay having children it is due to an inability to conceive. In the end, such women avail themselves of infertility treatments and go on to conceive a pregnancy. Studies show that there are a higher number of stillbirths in women who use advanced reproductive technologies. A large portion of the losses are due to multiples; however, even women who have single pregnancies through the use of IVF or ovarian stimulation, have increased risk for premature, low birth weight and small for gestational age babies. The main category of stillbirth experienced by women who have IVF or assisted reproduction is "unexplained."
Other Stillbirth Risk Factors
There are several more risk factors that influence stillbirth, including:
· Thrombophilias (blood clotting)
· Systemic Lupus Erythematos (SLE)
· Medical Risk Factors such as placental problems, IUGR, and preeclampsia
· Chromosomal issues and birth defects
Stillbirth is a difficult issue. Learn more about it and how it affects couples in this section.