Definition
The number of live births under 37 weeks gestation divided by the total number of live births over the same time period.Numerator
Number of live born infants born less than 37 weeks gestation.Denominator
Total number of live births.Data Interpretation Issues
Reporting of preterm birth (PTB) trends has been complicated by a change in how gestational age (GA) is reported by the National Center for Health Statistics. PTB is defined as a birth less than 37 weeks gestation. Historically, GA was calculated by the mother's last menstrual period (LMP) and PTB rates were reported this way. Since the 2003 revision of the birth certificate, GA is also reported by obstetric estimate (OE), which is considered more accurate. Beginning in 2007, national rates are reported using OE and are not consistent with rates reported before 2007. Utah rates have been reported using OE since 1996.Why Is This Important?
Preterm birth, birth before 37 weeks gestation, is the leading cause of perinatal death in otherwise normal newborns and is a leading cause of long-term neurological disabilities in children. Infants born preterm bear the biggest burden of infant deaths, with 68% of infant deaths from 2017-2021 born before 37 weeks. Babies born preterm also have increased risks for long-term morbidities and often require intensive care after birth. Healthcare costs and length of hospital stay are higher for premature infants. For a preterm infant, average hospital stays are about 10 times longer than all infants combined. Utah inpatient hospital discharge data (2022) indicate that average hospital charges for a premature infant were $125,128 compared to $16,220 for all deliveries combined. These same data indicate that the average length of stay for a premature infant was 22 days compared to 2 days for all newborn infants.Other Objectives
The Healthy People 2030 has an objective of reducing Preterm Births- MICH-07 with a baseline of 10% (2018) and a goal of 9.4%.How Are We Doing?
The Utah preterm birth rate increased from 8.8% in 1990 to a high of 10.1% in 2005. The rate has remained under 10% from 2006 to the present. The percentage of infants born preterm in Utah was 9.35% in 2023 and 2022, a decrease from 9.88% in 2021.How Do We Compare With the U.S.?
The U.S. preterm birth rate was 10.41% in 2023, essentially unchanged from 10.38 in 2022. The percentage of infants born preterm decreased from 2007 (the first year for which national data are available based on the obstetric estimate of gestation) to 2014, and generally increased from 2015 to 2021 when it reached a 15-year maximum of 10.49%. Available from:
[https://www.cdc.gov/nchs/data/databriefs/db507.pdf].
The Utah 2022 rate of 9.35% is below the national rate of 10.38% and marginally below the Healthy People 2030 goal of 9.4%.
In 2007, the U.S. began reporting preterm birth rates based on obstetric estimates rather than based on the last menstrual period (LMP) making it difficult to compare Utah to the U.S. farther back than 2007. The obstetric estimate has been shown to more accurately reflect the true gestational age of the infant than LMP.What Is Being Done?
Approximately half of the preterm births in Utah are due to complications of the pregnancy (multiple births, placental problems, fetal distress, infections) or maternal health factors such as high blood pressure or uterine malformations. The remaining preterm births have unexplained causes. In an effort to reduce the preterm birth rate, emphasis is being placed on maternal preconception health to help women achieve optimal health prior to pregnancy. Some ways women can achieve optimal health include stopping the use of tobacco and alcohol, controlling chronic diseases such as diabetes and high blood pressure, and obtaining an optimal pre-pregnancy weight. Early and continuous prenatal care is encouraged to detect problems that may arise during pregnancy. Education should be provided on the urgent maternal warning signs ([https://www.cdc.gov/hearher/maternal-warning-signs/index.html]) and the importance of recognition and treatment for these symptoms. Standards for assisted reproductive technology should be followed to reduce the frequency of twins or higher-order multiple pregnancies. Pregnant women should also be referred for appropriate services such as Women, Infant, and Children (WIC) and psychosocial counseling.
