Depression During Pregnancy Can Double Risk of Premature Birth

Mothers-to-be who suffer from depression have been shown to have twice the risk of delivering a premature infant than pregnant women that have no symptoms of depression. This risk for premature infants increases as the symptoms of depression become more severe.In a new study, which is among the first to study depression and premature births in a representative and diverse population in the U.S., looked at approximately 791 pregnant Kaiser Permanente members that were in San Francisco City and county from October of 1996 through October of 1998. According to the researchers, the findings provide preliminary evidence that reproductive and social risk factors, stressful events, and obesity may exacerbate the depression-premature delivery link. Because the majority of the mothers in this study did not take anti-depressants, the study provides a clear look at the link between the premature delivery and depression.The researchers interviewed the mothers around their tenth week of pregnancy and found that 41 percent reported significant or severe depression symptoms. The women that had symptoms that were less severe had a 60 percent higher risk of premature birth when compared with the women without significant symptoms of depression. However, the women that had severe symptoms of depression had more than twice the risk as the other for premature birth.The lead author of the study, Dr. De-Kun Li, who is a reproductive and perinatal epidemiologist at Kaiser Permanente’s Division of Research located in Oakland, said, “Preterm delivery is the leading cause of infant mortality, and yet we don’t know what causes it. What we do know is that a healthy pregnancy requires a healthy placenta, and that placental function is influenced by hormones, which are in turn influenced by the brain.”The study has also added emerging evidence that depression during the early stages of pregnancy can interfere with the neuroendocrine pathways and in turn, function of the placenta. The placenta and neuroendocrine functions play a key role in maintaining a healthy pregnancy and determining when labor will occur.Li also stated, “Postpartum depression has been extensively studied and discussed by the public, but depression during pregnancy is significantly under-recognized and under-diagnosed. Clinicians should pay close attention to depression during pregnancy to catch it early…. If prenatal depression is indeed as prevalent as reported in this and other studies and doubles the risk of preterm delivery, then brining depression to the forefront of prenatal care could lead to a significant reduction of preterm deliveries.”Premature birth is the leading medical expenditure for infants. It is estimated to cost the United States $26 billion dollars annually. Presently, other than previous history of premature births, and some complications during pregnancy, very little is known of the origins and risk factors contributing to premature delivery. The key strengths of this study are that it ascertained that symptoms of depression early in the pregnancy, long before the premature birth occurred, therefore avoiding recall bias. In addition, the study was not clouded by the women taking medication for depression because only 1.5 percent of the study population had been prescribed antidepressants and could be excluded from the study analyses.