Changes in cervical neutrophil elastase levels during the menstrual cycle.

PurposeCervical mucus plays an important role in host defense mechanisms and is involved in the ascendance of sperm. To determine the change of neutrophil mediators contained in cervical mucus, we measured total neutrophil elastase (NE) levels throughout the menstrual cycle.MethodsCervical NE concentrations in 31 healthy women having regular ovulatory cycles were measured during the follicular, ovulatory and luteal phases.ResultsThe cervical NE levels during the follicular, ovulatory and luteal phases were 0.73 ± 0.57 (mean ± SD), 0.29 ± 0.33 and 1.32 ± 1.24 μg/ml, respectively. The NE concentrations during the ovulatory phase were significantly lower than the other phases.ConclusionsThe decrease in total cervical NE level during the ovulatory phase suggests that neutrophil activity in cervical mucus is depressed around ovulation. The decreased cervical NE levels and the depressed neutrophil activity in cervical mucus at ovulation may be suitable for sperm passage through the cervical canal.