A total of 341 fertilized and 37 unfertilized oocytes from 63 intracytoplasmic sperm injection (ICSI) treatment cycles were included for retrospective assessment using the Embryoscope time-lapse video system. The second polar body (pb2) extrusion occurred at 2.9±0.1 h (range 0.70-10.15 h) relative to sperm injection. All oocytes reduced in size following sperm injection (p<0.05) with shrinkage ceasing after 2h in the unfertilized and at pb2 extrusion in the fertilized oocytes. Pb2 extrusion was significantly delayed for women aged >38 years compared to those <35 years (3.4±0.2 vs. 2.8±0.1, p<0.01) or 35-38 years (3.4±0.2 vs. 2.8±0.1, p<0.01), but timing was not related to the Day 3 morphological grades (1-4) of subsequent embryos (2.9±0.1, 2.9±0.1, 2.8±0.2 and 3.0±0.1; p>0.05 respectively). A shorter time of first cleavage division relative to either sperm injection or pb2 extrusion is associated with both top grade (AUC=0.596 or 0.601, p=0.006 or 0.004) and usable embryos (AUC=0.638 or 0.632, p=0.000 respectively) on Day 3. In summary, (i) pb2 of human oocytes extrudes at various times following sperm injection, (ii) the timing of pb2 extrusion is significantly delayed when female age >38 years, but not related to subsequent embryo development, (iii) all human oocytes reduce in size following sperm injection, (iv) completion of pb2 extrusion in the fertilized oocytes is a pivotal event in terminating shrinkage of the vitellus, and (v) time to first cleavage division either from sperm injection or pb2 extrusion is a significant predictive marker for embryo quality on Day 3.
Scientists working in assisted reproduction [members of Scientists in Reproductive Technology (SIRT) Australia, and subscribers of the online forums EmbryoMail and Quartec] were invited to complete an online questionnaire on the use of human blood products in assisted reproductive technologies (ART). A total of 260 started the questionnaire, with 208 (80%) completing it. A total of 62% of respondents had worked in human ART ≥8 years and 68% had post-graduate qualifications. The majority (82%) reported using products of animal or human origin, with 75% knowing why protein was added to culture media and 41% not worried by this. Almost half (49%) of respondents were unaware of regulations surrounding the use of human blood products in health care and 70% were unaware of adverse events involving human blood products in human ART. Most respondents (70%) indicated that they were not concerned about infections such as hepatitis, but agents such as prions were a cause for concern (57%). A total of 57% of respondents were unaware of alternatives, but 77% would use a suitable alternative. Using blood products in human ART is surrounded by a lack of awareness, often independent of respondents' qualifications or experience. A better understanding of these products and possible alternatives is required if informed decisions about their suitability are to be made.