DNM2 expression in the offspring of Vav-Cre x Dnm2^flox (targeting the hematopoietic system) mice.Dnm2 expression, normalized to actin, in Dnm2^het mice and in CTRL mice by RT-PCR (A) and western blot (B) in BM cells. Different breeding combinations based on genotypes were tested to determine aspects of Dnm2^het phenotype. The number of pregnancies was documented. Among breeding mouse colonies, some Dnm2^het females (positive for Vav-Cre and Dnm-2^flox) became distressed when pregnant, at middle age (between 35 weeks and 45 weeks of age). We named this distressed state as pathologic pregnancies for the purpose of designating this group in this study. This phenotype was not observed in pregnant mice younger than 34 weeks of age or in any of the mice that harbored other sets of genotypical combinations. The comparison of pathologic pregnancies in different mouse group is indicated and illustrated (C,D,E,F).