Are vaginal fluid concentrations of prolactin, alpha-fetoprotein and human placental lactogen useful for diagnosing ruptured membranes?

Vaginal fluid levels of prolactin (Prl), alpha-fetoprotein (AFP) and human placental lactogen (hPL) were assayed to investigate their usefulness in the diagnosis of ruptured membranes. Fifty-two patients at term were divided into those with intact membranes, and those with ruptured membranes. In patients with intact membranes the concentration of all three substances was low with few exceptions. The mean vaginal concentrations of the three proteins were significantly higher in patients with ruptured membranes, but low values were also found in this group. It is concluded, that because of the overlap between the values, Prl, AFP and hPL measurements in vaginal fluid do not represent a useful advance in the assessment of rupture of the membranes.