The significance of premature luteinization in an oocyte-donation programme.

BACKGROUND Several evidences indicate that premature luteinization (PL) may affect IVF outcome. The primary end-point of the present study was to verify the effect of PL on the pregnancy rate (PR) of our oocyte-donation programme. METHODS PL was defined as serum progesterone > or = 1.2 ng/ml on the day of HCG. We analysed retrospectively 240 oocyte-donation cycles in which 120 women donated twice, with PL in the first donation cycle and no PL in the following one, acting as its own control. Recipients (n = 240) were divided in two groups according to the presence of PL (n = 120) or not (n = 120). Both groups were compared regarding donor cycle parameters and recipient cycle outcome. RESULTS There was no difference in PR between the groups (55.7 versus 54.4%, respectively). The number of total oocytes (18.2 +/- 0.6 versus 20.8 +/- 0.6; P = 0.003) and the number of mature oocytes retrieved (16.9 +/- 0.6 versus 19.4 +/- 0.6; P = 0.005) were different among donors with progesterone < 1.2 ng/ml and PL, respectively. There were no differences between the oocyte recipients in fertilization, cleavage, embryo division on day 3, blastocyst development or fragmentation rates. The number of embryos transferred, number of embryos cryopreserved, and implantation and miscarriage rates were similar between the groups. CONCLUSION PL does not appear to have a negative impact on ongoing PR in our oocyte-donation programme.