Erratum to: J Assist Reprod Genet (2011) 28:107–110

DOI 10.1007/s10815-010-9490-8

The original version of this article unfortunately contains errors in Abstract, Results and Discussion sections. The details are as follows:

Abstract where it says “Abnormal fertilization rate was 1.7 %” should read “Abnormal fertilization rate was 27 %”.

In results where it says “The frequency of abnormally fertilized oocytes (1Pn and 3Pn) was 1,7 %” should read “The frequency of abnormally fertilized oocytes (1Pn and 3Pn) was 27 %”.

In discussion the paragraph starting “We found that after IVM, 1,7 %.....”, we would like to CHANGE the statement to “We found that after IVM, 27 % of the fertilized oocytes present abnormal pronuclear formation, particularly 3Pn possibly due to second polar body retention. This frequency is much higher than that reported (2.5 %) after insemination by IVF or ICSI of more than 5000 human oocytes in conventional IVF/ICSI cycles [13] and it is also higher than the observed rate of polyploidy after conventional ICSI in our service. The reason for the elevated rate of 3Pn zygotes after IVM is not clear, however, it can be assumed that failure of second polar body extrusion after ICSI in IVM cycles is related to cytoskeletal abnormalities, possibly caused by manipulation or incomplete cytoplasmic maturation.