Randomized autocontrolled comparison of the embryo culture performance of Nunc and Falcon petri dishes

Purpose: Our purpose was to compare the embryo culture performance of two t ypes of petri dishes (Nunc and Falcon). Methods: Mouse-zygotes were cultured up to the expanded blastocyst stage in both types of dishes. The oocytes from 50 in vitro fertilization cycles we re ramdomly divided between the two types of dishes. Fertilization, cleavag e, and embryo quality were compared. Oocytes from another 50 cycles were al l cultured at random in either type of dish. Pregnancy and implantation rat es were compared between the two types. Results: Of 91 mouse zygotes, 81 cleaved to two-cell-stage embryos, and 64 became expanded blastocysts in Falcon dishes; of 99 zygotes, 81 cleaved to two-cell-stage embryos and 66 became expanded blastocysts in Nunc dishes. O f 248 oocyte-cumulus complexes (OCC), 145 fertilized in Falcon dishes, and of 269 OCC, 175 fertilized in Nunc dishes. The high quality embryo ratio wa s 51 out of 118 in Falcon dishes, not different from that in Nunc dishes, 5 8 out of 139. In Falcon dishes 72 out of 118 embryos were at least at the f our-cell stage after 45 hi; versus 70 out of 139 in Nunc dishes. Twenty-thr ee clinical pregnancies were obtained in the first 50 cycles with sibling o ocytes. In the second group, with randomization of the cycles between Nunc and Falcon, 8 pregnancies were obtained in the Nunc and 10 in the Falcon di shes. The implantation rate in this second group of 50 cycles was 9 out of 61 in Falcon and PI out of 57 in Nunc dishes. Conclusions: No differences were observed.