Recurrent endometriosis: a review of biological and clinical aspects.

The recurrence of pelvic endometriosis some time after the initial treatment is a common finding in clinical practice. When symptoms of endometriosis reappear several months after treatment, it is difficult to distinguish between recurrence and persistence of the disease. In this review, the current hypotheses about the biological basis of endometriosis recurrence/persistence are discussed.

Effect of peritoneal fluid, follicular fluid, and their volumetric mixture on acrosomal reactivity in vitro.

Objective: To determine the effects of peritoneal and follicular fluids (PFs, FFs) on sperm acrosomal reaction (AR).

Design: Prospective, randomized study.

Setting: Three hospital-based infertility units.

Steroid receptors in human spermatozoa.

The presence of steroid binding sites in (or on) human spermatozoa was first suggested in the late 1970s, by studies showing that some steroids were able to influence sperm function. Subsequently, several effects exerted on spermatozoa by biological fluids, such as follicular fluid, were found to be probably linked to the action of steroids, and among them progesterone. Since the effects of progesterone on spermatozoa were rapid, dose-dependent and not affected by progesterone conjugation with high molecular weight proteins unable to cross the plasma membrane, the existence of a novel class of non-genomic progesterone receptors was strongly suspected.

Effect of peritoneal fluid supplemented with exogenous progesterone on sperm motility in vitro.

Since progesterone has been claimed to induce acrosomal reaction and hyperactivated motility of human spermatozoa, the present study was undertaken to determine if its presence at concentrations similar to those of peri-ovulatory follicular fluid could influence the effect of peritoneal fluid on sperm motility in vitro. To this end, 11 sperm samples were incubated at 37 degrees C with five peritoneal fluids with/without exogenous progesterone, and sperm motility was assessed using a computer-assisted analyser at time (t) = 0, 2.5, 5 and 24 h.