Comparative Study of Three Amniotic Fluid Markers in Premature Rupture of Membranes: Prolactin, Beta Subunit of Human Chorionic Gonadotropin, and Alpha-Fetoprotein

Abstract

Objective: To evaluate whether prolactin, α-fetoprotein (AFP) or B-human chorionic gonadotropin (BHCG) is the most effective marker in vaginal fluid for diagnosing prelabor rupture of membranes (PROM). These proteins are present in amniotic and vaginal fluid and have been reported to be potent markers of PROM, but have not been used clinically nor compared to each other. Study Design: A total of 100 pregnant women between 28 and 37 weeks of gestation were recruited for the study. Patients were divided into 2 groups. The first group consisted of 50 pregnant women diagnosed with ruptured membranes. The second group consisted of 50 normal pregnant women seen during routine antenatal clinic visit (control) group. All women underwent speculum examination aiming to sample prolactin, BHCG and AFP in the vaginal fluid. Ultrasonographic examination for gestational age and amniotic fluid index measurement was performed. The electrochemoluminescence (ECLIA) method was used for quantitative measurement of the three proteins (the total duration of the assay was 18 min). Results: Vaginal fluid concentrations of the three markers were significantly higher in the PROM group than in the control group (p < 0.001). Receiver operator curve analysis indicated that AFP had 94% specificity, sensitivity, positive and negative predictive values, and efficiency. The other two markers have lower specificity, sensitivity, positive and negative predictive values, and efficiency: 70, 76, 71.7, 74.5 and 73% for prolactin and 72, 84, 75, 81.8 and 78% for BHCG, respectively. Conclusion: This work demonstrates that of the three markers investigated AFP has the highest diagnostic performance. Using the ECLIA method it can be an ideal marker for diagnosing PROM particularly in equivocal cases. The technique could be introduced into laboratory tests to meet clinical needs.

Comparative analysis of four biomarkers in diagnosing premature rupture of membranes and their correlation with onset of labour

“…Our results were quite similar to that demonstrated by Shahin et al who reported sensitivity, specificity, positive predictive value, negative predictive value and accuracy of 94% each. 3 Similar findings with a high diagnostic performance were also reported by Ni et al from China in 2003. 7 Prolactin was reported to have an average diagnostic performance in our study with a cut off value of 23.56mg/ml.…”

“…3,[7][8][9][10][11][12] Our study demonstrated βhCG cut off value of 37.06 mIU/ml and the sensitivity, specificity, PPV,NPV and efficiency of 84%, 68%, 72.41%, 80.95% & 76% respectively. This observation was similar to that demonstrated by Shahin et al 3 .…”

“…The aforementioned limitations of the conventional testing methods have prompted investigators to seek alternative biochemical markers in amniotic fluid, such as prolactin, [3][4][5] alpha-fetoprotein, 3,6,7,26 β-subunit of human chorionic gonadotropin, 3,[7][8][9][10][11][12] fetal fibronectin, 6,13,14 diamine oxidase, 6,15,16 lactate, 17 creatinine, 7,18-21 urea, 17 and insulin growth factor binding protein-1. 14, 15 The rationale of assessing these markers stems from their high concentrations in amniotic fluid compared with normal vaginal secretions.…”

Diagnostic Modalities in Premature Rupture of Membranes

“…An ideal test should be rapid, accurate, noninvasive, inexpensive, easily-applicable, and available in cervicovaginal secretions when rupture of membranes has occurred, whereas it should be absent in case of intact membranes. This search enabled conducting studies on fetal fibronectin (fFN), IGFBP-1, Alpha Fetoprotein (AFP), beta-subunit of human chorionic gonadotropin (β-hCG), prolactin, creatinine, urea, lactate, and PAMG-1 (14)(15)(16)(17)(18)(19)(20). Recently IGFBP-1 and PAMG-1 are included in popular diagnostic methods as simple bedside tests.…”

Gonadotropina coriónica en flujo vaginal para el diagnóstico de rotura prematura de membranas

“…Se han evaluado las concentraciones vaginales de diaminoaxidasa, prolactina, alfafetoproteína (AFP), fibronectina fetal y proteína 1 fijadora del factor de crecimiento similar a la insulina (IGFBP-1) (5-11). Sin embargo, la prolactina y la AFP no son marcadores útiles en la RPM debido a que sus concentraciones se sobreponen entre las embarazadas con y sin RPM (6)(7)(8)(9). Más aún, la liberación crónica de fibronectina previo al parto en embarazadas con membranas intactas puede llevar a resultados falso positivos (9,10).…”