Cervicovaginal prolactin: a marker for spontaneous preterm delivery.
OBJECTIVE
Our purpose was to determine whether the presence of prolactin in cervicovaginal washings is associated with preterm birth.


METHODS
A cohort of 80 patients underwent a washing of the ectocervix and vaginal fornices with a normal saline solution. The cohort consisted of two groups: 40 inpatients requiring tocolysis and 40 asymptomatic outpatients. The saline solution aspirates were centrifuged, the supernatant was stored at -70 degrees C, and a radioimmunoassay for prolactin was run in batch fashion. A prolactin concentration greater than the detection limit of the assay was considered a positive test result.


RESULTS
Prolactin was identified in significantly more symptomatic patients than asymptomatic controls (50% vs 5%, p < 0.0001). In symptomatic patients cervicovaginal prolactin had an 80% positive predictive value and a 65% negative predictive value for delivery at < or = 34 weeks' gestation. Patients testing positive for prolactin had significantly shorter latency from testing to delivery (16 +/- 17 vs 34 +/- 24 days, p = 0.02) and had significantly lower birth weights (1985 +/- 729 vs 2583 +/- 696 gm, p = 0.01) compared with patients testing negative. Prolactin was also identified in two asymptomatic patients, both of whom were delivered before term.


CONCLUSIONS
Cervicovaginal prolactin is a biochemical marker for preterm delivery, a shorter latency period to delivery, and lower birth weight in symptomatic patients. This test may also prove to be a valuable marker for preterm birth in asymptomatic women.
O'Brien
J M
JM
Department of Obstetrics and Gynecology, University of Tennessee, Memphis.
Peeler
G H
GH
Pitts
D W
DW
Salama
M M
MM
Sibai
B M
BM
Mercer
B M
BM
D000328:Adult; D015415:Biomarkers / Q000032:analysis; D002584:Cervix Uteri / Q000378:metabolism*; D015331:Cohort Studies; D036861:Delivery, Obstetric; D005260:Female; D006801:Humans; D007230:Infant, Low Birth Weight; D007231:Infant, Newborn; D007752:Obstetric Labor, Premature / Q000175:diagnosis* / Q000378:metabolism; D011237:Predictive Value of Tests; D011247:Pregnancy; D011388:Prolactin / Q000032:analysis*; D011863:Radioimmunoassay; D012044:Regression Analysis; D012680:Sensitivity and Specificity; D012965:Sodium Chloride / Q000008:administration & dosage; D007507:Therapeutic Irrigation; D013997:Time Factors; D014621:Vagina / Q000378:metabolism*
D015415:Biomarkers; D012965:Sodium Chloride; D011388:Prolactin