PartoSure Test

Worldwide 15 million babies are born prematurely each year (2). Accurately assessing the risk of preterm labor (PTL) is difficult and has significant implications in the health of patients. PTL can result in health problems at birth and later in life for the baby, including cerebral palsy, intellectual disabilities, chronic lung disease, blindness and hearing loss (3).
Clinical evaluation alone is limited in its ability to predict imminent delivery. Studies show 85% of patients admitted for threated PTL do not deliver within 7 days. Thus, the accurate risk assessment of imminent preterm delivery in patients with suspected PTL remains an important clinical concern for institutions of all types. This is particularly true with respect to both the administration of corticosteroids, which have an optimal benefit within 7 days of administration, as well as the transfer of patients to a tertiary care center capable of caring for the birth of a premature infant (4).
Placental alpha-microglobulin-1 (PAMG-1), a protein released from decidual cells into the amniotic cavity throughout pregnancy, was first described by Petrunin et al. in 1975 (5,6). Its presence in cervicovaginal discharge when labor and delivery are imminent is likely due to the transudation of the protein through pre-existing pores in the chorioamniotic membranes during uterine contractions and, potentially, degradation of the extracellular matrix of fetal membranes due to an inflammatory process of labor or infection (7).

PartoSure is a lateral flow, immunochromatographic assay designed to identify the presence of human placental-alpha-microglobulin-1 (PAMG-1). The test employs monoclonal antibodies sufficiently sensitive to detect 1 ng/ml of PAMG-1. For the analysis, a sample of cervicovaginal discharge collected by vaginal swab is extracted into a solvent. The presence of PAMG-1 antigen is then detected by inserting a lateral flow test strip into the vial. The sample flows from an absorbent pad to a nitrocellulose membrane, passing through a reactive area containing monoclonal anti-PAMG-1 antibodies conjugated to a gold particle. The antigen-antibody complex flows to the test region where it is immobilized by a second anti-PAMG-1 antibody. This event leads to the appearance of the test line. Unbound antigen-antibody complexes continue to flow along the test strip and are immobilized by a second antibody. This leads to the appearance of the internal control line.

The simple 4-step test procedure* detects placental alpha microglobulin-1 (PAMG-1) a protein found in amniotic fluid (1).

1. Collect sample of vaginal discharge with sterile collection swab (no speculum required).
2. Rinse specimen swab in solvent vial. Discard swab.
3. Insert amniotic fluid test strip into vial and remove if 2 lines are visible, or at 5 minutes sharp.
4. Results are observed and recorded.

*Please refer to package insert for complete instructions for use.

The PartoSure test is for use by healthcare professionals to aid in assessing the risk of preterm delivery in pregnant women when they report signs and symptoms of early preterm labor.