pediatrics
Preterm Infants
Etiology of Prematurity
Preterm delivery may be Indicated because of obstetric risks or complications Spontaneous because of preterm labor The American College of Obstetricians and Gynecologists (ACOG) recommends late preterm delivery in conditions such as Complications , ACOG recommends delivery as early as 32 weeks in selected cases involving multiple gestation with complications. Quasi-elective delivery earlier than 32 weeks is done on a case-by-case basis to manage severe maternal and/or fetal complications. In an individual patient, spontaneous preterm delivery may or may not have an obvious immediate trigger (eg, infection [see Intraamniotic Infection and Past obstetric or gynecologic history: Prior Preterm Delivery (highest risk) Prior cervical conization procedure (cold knife cone or loop electrosurgical excision procedure) Prior dilation and curettage procedure for Recurrent Pregnancy Loss or Cervical Insufficiency , Diabetes Mellitus (DM) None None Chronic Kidney Disease None Obstetric risk factors related to the current pregnancy: Short interpregnancy interval (< 6 months) Extremes of prepregnancy weight (underweight or obese) or of weight gain during pregnancy (gaining more or less weight than recommended) Pregnancy achieved by In vitro fertilization (IVF) None Multifetal Pregnancy (eg, twins, triplets) Vaginal bleeding in early pregnancy Placental Abruption (Abruptio Placentae) or placenta previa Preterm Labor None Preeclampsia and Eclampsia None Infections (eg, Bacterial Vaginosis (BV) , Diabetes Mellitus (DM) or Prelabor Rupture of Membranes (PROM) None Little or no prenatal care Certain congenital defects (fetuses with structural Overview of Congenital Cardiovascular Anomalies are nearly twice as likely to be delivered prematurely as fetuses without congenital heart defects) Multiple gestation is an important risk factor; 59% of twins and > 98% of higher-order multiples are delivered prematurely. Many of these infants are very preterm; 10.7% of twins, 37% of triplets, and > 80% of higher-order multiples are delivered at < 32 weeks of gestation ( General references ). Lifestyle or demographic risk factors: Younger or older Maternal Age (eg, < 16 years, > 35 years) Non-Hispanic Black or American Indian/Alaska Native women (in the United States) Undernutrition Smoking and Other Tobacco Use None Substance Use Disorders None Exposure to certain environmental pollutants Domestic Violence None Stress or lack of social support Long work hours with long periods of standing It is unclear how much risk some of these lifestyle or demographic risk factors contribute independent of their effect on other risk factors (eg, nutrition, access to medical care). 1.American College of Obstetricians and Gynecologists’ Committee on Obstetric Practice, Society for Maternal-Fetal Medicine: Medically Indicated Late-Preterm and Early-Term Deliveries: ACOG Committee Opinion, Number 831.Obstet Gynecol138(1):e35-e39, 2021. doi: 10.1097/AOG.0000000000004447 2.National Institute of Child Health and Human Development: What are the risk factors for preterm labor and birth? Accessed October 6, 2023. 3.Saccone G, Perriera L, Berghella V: Prior uterine evacuation of pregnancy as independent risk factor for preterm birth: A systematic review and metaanalysis.Am J Obstet Gynecol214(5):572-591, 2016. doi: 10.1016/j.ajog.2015.12.044 4.Hamilton BE, Martin JA, Osterman MJ: Births: Provisional Data for 2021. National Center for Health Statistics. National Vital Statistics System, Vital Statistics Rapid Release Program, no 20. Hyattsville, MD. National Center for Health Statistics. 2022. 