Spontaneous contractile activity, glucose (Glu), glycogen (GLY), triglyceride (TG) metabolism and eicosanoid production, was evaluated in isolated uterine strips from control and non-insulin-dependent diabetic rats on day 10 of pregnancy. Metabolism of Glu, levels of GLY and TG and eicosanoid production were also studied in day 10 embryos obtained from both experimental groups. "In vitro" isometric developed tension (IDT), was similar at 0 hr in control and diabetic uterine preparations, but IDT was decreased after a 60 min incubation in the diabetic group. The frequency of contractions (FC) was similar at 0 hr and after 60 min incubation in both experimental groups. On the other hand, the production of 14CO2 from U14C-glucose was lower in isolated uteri and embryos obtained from diabetic rats than in controls. Initial TG levels were similar in uteri isolated from control and diabetic rats, and higher in embryos obtained from diabetic mothers than in controls. Levels of TG in uterine strips suspended in Glu or Glu-free medium did not differ at 0 hr or at 60 min either in controls or in diabetic rats. On the contrary GLY levels in uterine strips from diabetic animals were higher than in controls, whereas in embryos from diabetic mothers GLY levels were similar to controls. Levels of GLY in uterine strips from controls and diabetic animals decreased after 60 min incubation only in the absence of Glu in the incubation medium. Production of PGE2, PGE1, 6-keto-PGF1 alpha, PGF2 alpha, TXB2 and LTB4 was studied in uterine strips and embryos obtained from control and diabetic rats. No differences were found between control and diabetic uterine prostanoid production, but lower production of LTB4 was observed in diabetic uteri. However production of PGE2 and PGF2 alpha was greater in embryos obtained from diabetic mothers than in controls. In this study, we observed lower uterine metabolic alterations than in the pancreatectomized diabetic rat model studied previously, but important anomalies in the embryos obtained from non-insulin-dependent diabetic mother were found.