Introduction: Preterm birth is a major cause of neonatal morbidity and mortality in developed countries.
The placental alpha-microglobulin-1 (PAMG-1) is a protein that can be found in high
concentrations in the amniotic fluid and in lower concentrations in the vaginal secretion
in patients with signs of preterm labor without rupture of membranes. We aimed to
evaluate PAMG-1 diagnostic kit in the prediction of preterm birth.
Material and methods: We included 119 patients (between 24 0/7 and 36 6/7 gestational weeks) in this prospective
observational trial. We included patients with symptoms of preterm labor and gestational
age-matched controls. We evaluated the sensitivity (SN), specificity (SP), positive
predictive value (PPV) and negative predictive value (NPV) of PAMG-1 measurements
compared to transvaginal cervical length (CL) measurements. The performance of the
test was calculated within 48 hours, 7 days and 14 days. We performed a subgroup analysis
in symptomatic patients with CL between 15 and 30 mm.
Results: We detected superior SP and PPV in the PAMG-1 compared to CL group at all time points.
SN was higher in the CL group and NPV was similar in both groups. PAMG-1 performance
was confirmed within the subgroup (CL: 15 – 30 mm) of symptomatic patients, where
CL measurements are at least accurate predicting preterm birth.
Conclusions: The novel PAMG-1 test has a high PPV and SP compared to other commercially available
bed-side tests. Our study suggests clinical usefulness of the PAMG-1 test, especially
in addition to cervix length measurements. Its utilization may reduce unnecessary
hospitalizations and overtreatment.