The acute release of maternal prolactin by instrumental cervical dilatation simulates the second stage of labor.

Objective: We hypothesize that artificial stimulation of the cervix causes an acute secretion of maternal prolactin (PRL) that mimics PRL secretion during the second stage of human labor.

Methods: Eighteen women scheduled for first-trimester therapeutic abortion had a blood sample drawn at the following times: before and after laminaria tent (LT) insertion for cervical ripening, 18-24 hours later upon entry in the procedure room, after LT removal, during instrumental cervical dilatation and uterine evacuation by suction curretage, soon after evacuation, and 1/2 hour and 1 hour after evacuation. Local cervical anesthesia, intravenous analgesics, and sedation were administered before the procedure.

Maternal prolactin secretion is phasic during induced term and post-term labor.

Objective: We hypothesized that regimens of labor induction do not alter the biphasic secretion of maternal prolactin (PRL) seen during spontaneous labor.

Methods: Serial blood samples drawn from 12 women before, during, and after induced labor were assayed for PRL and hCG and compared with cervical dilatation and uterine contraction frequency (UCF). Induction methods were cervical ripening with dinoprostone gel (Prepidil) followed by oxytocin infusion (n = 1), amniotomy followed by oxytocin (n = 4), oxytocin followed by amniotomy (n = 3), amniotomy only (n = 2), and oxytocin only (n = 2).

Phasic maternal prolactin secretion during spontaneous labor is associated with cervical dilatation and second-stage uterine activity.

Objective: In this study, we attempted to determine the physiologic roles of prolactin (PRL) and hCG during labor.

Methods: Serial blood samples were collected from 19 women (15 multiparous and four nulliparous) before, during, and after labor; assayed for PRL and hCG; and compared with cervical dilatation and uterine contraction frequency.

Results: Prolactin levels decreased in association with progressive cervical dilatation during the first stage of labor and reached a nadir at full dilatation.

Y body association with morphologic heterogeneity of human sperm.

Objective: The purpose of this study was to determine a possible association between the Y body and sperm head shape, since sperm head shape may be a factor that influences the rate of migration of X- and Y-bearing sperm cells.

Materials: Sperm cell (n = 1,065) preparations from seven donors were fluorochrome stained for the Y body, and area and shape of Y body-positive and -negative cells were measured from digitized images. The distributions of the segregated cell population measurements were statistically analyzed nonparametrically.

Quantitative analysis of the effect of freezing on donor sperm motion kinetics.

One hundred ninety-two semen specimens from 14 donors were analyzed on a CellSoft Semen Analyzer (CRYO Resources, New York, NY) before and after freezing. Mean post-thaw motility decreased by 52%. Correlation of the percent decrease in post-thaw versus prefreeze motility was significant but of poor predictive value.