Postfertilization development of untreated and PARP inhibitor-treated mouse embryos.

*PJ-34 or 5-AIQ was added 1 hr before IVF or ICSI and removed 6 hrs later (Exp. 2), added 6 hrs after IVF or ICSI (Exp. 3), and added 1 hr before IVF or ICSI and continuously treated for subsequent 24 hrs (Exp. 4). Inhibitors were included in the medium at the designated doses and the developmental effects were shown. Both PJ-34 and 5-AIQ were used for IVF and PJ-34 was used for ICSI. Development of untreated embryos was assessed as positive control (Exp. 1). Each experimental procedure was illustrated in Figure 2A. **Percentage is calculated by the formula: . a, bStatistic significance is compared with number of untreated oocytes or embryos by t-test (p<0.01 (a), p<0.05 (b)).