In vivo diabetic blastocyst transfers. Blastocyst stage embryos, recovered 72 h after human chorionic gonadotropin and mating from either streptozotocin-induced diabetic mice or control mice were transferred into nondiabetic pseudopregnant female recipients. A and B, Resorption or failed pregnancy rates and malformation rates were higher in diabetic blastocyst transfers compared with control (six transfer experiments for each condition). In addition, the diabetic blastocyst transfers were significantly smaller than controls. C and D, Diabetic blastocyst transferred embryos experienced higher rates of anterior and posterior neural tube closures, as well as skeletal and limb abnormalities. *, P < 0.01.