380,000 infants are born preterm each year and account for 67% of infant deaths. Currently, there are no early, reliable, non-invasive indicators to determine the risk for spontaneous preterm birth before symptoms arise. Nevertheless, women who have delivered prematurely are at a 30% increased risk of recurrent preterm birth making a previous spontaneous preterm birth the strongest known risk factor for recurrence. Recently, investigators have reported that women who deliver spontaneous preterm have decreased collagen concentration and increased collagen disorganization early in gestation that can contribute to a mechanically weak cervix; however, the process of cervical remodeling after delivery is poorly understood and only a few studies have investigated collagen concentration and organization after birth. Due to a lack of noninvasive technology, it was never before possible to evaluate human cervical microstructure without a biopsy. For the first time, the opportunity to measure the collagen and elastic properties of the cervix noninvasively is possible with quantitative ultrasound (QUS). Innovative, noninvasive QUS technology specialized to detect microstructure changes in tissue has shown promise in detecting cervical changes in the pregnant rat cervix and in human pilot studies. In this prospective, longitudinal study, the aim is to determine the feasibility of conducting a yearlong study that evaluates whether changes in human cervical remodeling that led to spontaneous preterm birth continued in the postpartum period. Furthermore, investigators will attempt to fill the scientific gap in knowledge by determining if low ultrasound biomarkers (attenuation, backscatter coefficient, and shear wave speed) during pregnancy and postpartum were associated with spontaneous preterm birth. Ultimately, the goal is to determine the feasibility of conducting the study and to determine if ultrasound biomarkers will provide a scientific basis to accurately identify women at risk for recurrent spontaneous preterm birth.
Recurrent spontaneous preterm birth is a major public health problem. It is not known why women who have delivered prematurely are at an increased risk of another preterm birth; however, early changes in the cervix have been detected in women who deliver preterm. The process of cervical healing after delivery is poorly understood; therefore, this research will evaluate cervical changes in the postpartum period so that more can be learned about the cervix in the year after birth.
