Low accuracy found for tests used to predict risk of spontaneous preterm birth for women who have not given birth before

March 14, 2017

The use of two measures, fetal fibronectin (a protein) levels and transvaginal cervical length, had low predictive accuracy for spontaneous preterm birth among women who have not given birth before, according to a study appearing in the March 14 issue of JAMA.

Preterm birth, affecting approximately 1.2 percent of the deliveries in the United States, was responsible for 35 percent of the world's 3.1 million annual neonatal deaths in 2006. Current strategies to identify women at risk are largely based on prior pregnancy outcomes, but risk assessment in women pregnant for the first time is difficult. The combination of transvaginal cervical length and fetal fibronectin levels to identify women at risk has been studied, with conflicting results.

M. Sean Esplin, M.D., of Intermountain Healthcare, Salt Lake City, and colleagues conducted a study that included 9,410 women without prior childbirth who had transvaginal cervical length and vaginal fetal fibronectin levels reviewed at two study visits four or more weeks apart.

Among these women, 474 (5 percent) had spontaneous preterm births, 335 (3.6 percent) had medically indicated preterm births, and 8,601 (91 percent) had term births. The researchers found that fetal fibronectin levels and transvaginal cervical length had poor predictive performance as screening tests for spontaneous preterm birth before 37 weeks. The most commonly used clinical cutoff for transvaginal cervical length (threshold of 25 mm or less) identified a minority (23 percent) of spontaneous preterm births before 37 weeks. The addition of fetal fibronectin levels to transvaginal cervical length measurement did not increase the predictive performance of transvaginal cervical length alone. Fetal fibronectin levels of 50 ng/mL or greater at 16 to 22 weeks identified 30 of 410 women (7.3 percent) with spontaneous preterm birth and 31 of 384 (8.1 percent) at 22 to 30 weeks.

"These findings do not support routine use of these tests in such women," the authors write.
-end-
(doi:10.1001/jama.2017.1373; the study is available pre-embargo at the For the Media website)

Editor's Note: Please see the article for additional information, including other authors, author contributions and affiliations, financial disclosures, funding and support, etc.

The JAMA Network Journals

Related Preterm Birth Articles from Brightsurf:

Researchers develop app to determine risk of preterm birth
An improved mobile phone app will help identify women who need special treatments at the right time and reduce emotional and financial burden on families and the NHS.

Point-of-care diagnostic for detecting preterm birth on horizon
A new study provides a first step toward the development of an inexpensive point-of-care diagnostic test to assess the presence of known risk factors for preterm birth in resource-poor areas.

WVU biostatistician studies link between microbiome and preterm birth
Pregnant African American women are more likely than white women to give birth prematurely, but they're underrepresented in studies of preterm birth rates.

3D-printed device detects biomarkers of preterm birth
Preterm birth (PTB) -- defined as birth before the 37th week of gestation -- is the leading complication of pregnancy.

Association of quitting smoking during pregnancy, risk of preterm birth
This study of more than 25 million pregnant women reports on rates of smoking cessation at the start of and during pregnancy and also examines the association of quitting cigarette smoking and the risk of preterm birth.

Blood test developed to predict spontaneous preterm birth
Results from a multicenter study show that five circulating microparticle proteins found in first-trimester blood samples may provide important clues about risk of spontaneous preterm birth.

Scientists gain new insight on triggers for preterm birth
A group of scientists led by Ramkumar Menon at The University of Texas Medical Branch at Galveston have gained new insight on a poorly-understood key player in the timing of labor and delivery.

Medically assisted reproduction does not raise risk of preterm birth and low birth weight
Study shows that couples can decide about using medically assisted reproduction free from concerns about increasing the health risks to their baby.

Risk of preterm birth reliably predicted by new test
Scientists at UC San Francisco have developed a test to predict a woman's risk of preterm birth when she is between 15 and 20 weeks pregnant, which may enable doctors to treat them early and thereby prevent severe complications later in the pregnancy.

Preterm birth leaves its mark in the functional networks of the brain
Researchers at the University of Helsinki and the Helsinki University Hospital, Finland, have proven that premature birth has a significant and, at the same time, a very selective effect on the functional networks of a child's brain.

Read More: Preterm Birth News and Preterm Birth Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.