Effect of peritoneal fluid on in vitro cleavage of 2-cell mouse embryos: possible role in infertility associated with endometriosis

The purpose of this study was to evaluate the effect of peritoneal fluid (PF) on in vitro cleavage of 2-cell mouse embryos. PF was aspirated from the posterior cul-de-sac at laparoscopy and centrifuged, and the cell-free supernatant was heat-inactivated at 56 degrees C for 30 minutes and filtered (0.22 micron). Five percent PF in Ham's F-10 media was prepared and eight to ten 2-cell mouse embryos cultured for 72 hours. There were two study groups, one consisting of 10 PF samples from infertile patients with no endometriosis (PF-NE) and 18 from infertile patients with endometriosis (PF-E). Each sample was assayed along with a control consisting of media only. At 72 hours, greater than 50% of the embryos in the control groups reached the blastocyst and hatching stages. Individual PF samples in both study groups were classified as toxic if less than 50% of the embryos reached the blastocyst and hatching stages at 72 hours. Eight of the 10 samples in the PF-NE group were nontoxic and 14 of the 18 samples in the PF-E group were toxic (P less than 0.01). For evaluation of the overall effect of PF, all results in the PF-E group were pooled (162 embryos) and compared by the Mann-Whitney U test to pooled results in the PF-NE group (100 embryos). The embryonic stages in the PF-NE group were significantly more advanced than those in the PF-E group (P less than 0.001) at 24, 48, and 72 hours.(ABSTRACT TRUNCATED AT 250 WORDS)