Prevention of Preterm Parturition

This article reviews risk factors for preterm delivery, with special attention to previous preterm birth and a short cervix. Strategies for minimizing the risk of preterm birth among high-risk women, including progesterone supplementation and cerclage, are discussed. ForewordThis Journal feature begins with a case vignette highlighting a common clinical problem. Evidence supporting various strategies is then presented, followed by a review of formal guidelines, when they exist. The article ends with the author's clinical recommendations.StageA woman presents for prenatal care in the first trimester of her third pregnancy. Her first child was born at 30 weeks of gestation after preterm labor. Her second pregnancy ended in delivery at 19 weeks of gestation. How would you recommend reducing the risk of preterm birth in this pregnancy? The Clinical Problem In the United States, the annual rate of preterm births (before 37 weeks of gestation) reached a peak of 12.8% in 2006 and was 11.7% in 2011.(1) The rate in the United States remains nearly twice the rate in European nations.(2) Premature birth in the ... Prevention of Preterm Parturition Despite advances in neonatal care, preterm birth remains a leading cause of infant death in the United States, especially among blacks. Systemic changes in reproductive health care to reduce the incidence of multifetal pregnancies and scheduled births before 39 weeks of gestation that lack a medical indication have been temporally associated with decreased preterm birth rates. Strategies to identify and treat medical risk factors in early pregnancy (e.g., genitourinary infection and poor nutrition) have not been effective in reducing preterm birth rates. Previous preterm birth and a short cervix (20 mm, as measured by transvaginal ultrasonography) are major risk factors for preterm birth. The use of progesterone supplementation in women with a previous preterm birth, a short cervix, or both was shown in randomized trials to reduce the frequency of preterm birth and is recommended for women with these risk factors. Cervical cerclage reduces the risk of recurrent preterm birth among women with a short cervix.