Assessing preterm birth risk: from bulletin to bedside
Weighing in on the key messages from ACOG’s recent Practice Bulletin, Errol Norwitz, MD, PhD, reviews the evidence on the utility of preterm birth screening modalities, including cervical ultrasound, fetal fibronectin, salivary estriol, and home uterine-activity monitoring.
If the index of suspicion for PTD is high in a symptomatic woman, admit her for observation to exclude preterm labor.
If the index of suspicion for preterm delivery remote from term is high, the patient should be admitted for observation to exclude preterm labor. Antenatal corticosteroid and tocolytic therapy should be initiated, if indicated. Broad-spectrum antibiotic therapy has not been found to be useful in the setting of preterm labor with intact membranes, although there is a considerable body of evidence demonstrating its efficacy in the setting of ruptured membranes at less than 34 weeks.48,49 Tocolysis has not been shown to be effective once the fetal membranes are ruptured, and is best avoided in this setting.50
If there is no evidence of preterm labor and the index of suspicion for PTD is low, the patient may be discharged home, even if she is symptomatic. Careful follow-up should be arranged within 1 to 2 weeks, and the patient should be counseled to return to the office if the symptoms of preterm labor worsen. In this setting—and depending on the gestational age—it may be appropriate to screen the patient with either fFN or sonographic estimation of cervical length.
The author reports no financial relationship with any companies whose products are mentioned in this article.
