Pronuclear pattern does not predict morphokinetics behavior in human embryos.

The purpose was to investigate the correlation between pronuclei (PN) morphology and morphokinetic behaviors of derived embryos with time lapse monitoring (TLM) in assisted reproduction setting. Over time, PN morphology from PN appearance (PNA) to PN fading (PNF), PNF according to size, contact, number and position of nuclear precursor bodies (NPBs) within each PN and morphokinetics variables, including absolute time points, relative timing parameters, cleavage patterns and arrest rate, were evaluated using TLM. There were insignificant relationship between morphokinetics variables including tBP2, tPNA, tPNF, t2, t3, t4, t5, t6, t7, t8, S1, CC2, S2 and Z scoring according Z1 to Z4 (p > .05). Also, an insignificant relationship was noticed between uneven blastomeres, reverse cleavage embryos and Z scoring (p > .05). However, there were significant correlations between the rates of direct and arbitrary cleavage as well as arrested embryos and Z scores. Combined PN morphology and embryo kinetic evaluation were suggested in assisted reproduction programs.