Effect of a levonorgestrel intrauterine system on women with type 1 diabetes: a randomized trial. Contraception in perimenopausal women with diabetes mellitus. Oral contraception in diabetic women. A cross-over study on serum and high density lipoprotein (HDL) lipids and diabetes control during progestogen and combined estrogen/progestogen contraception. Oral contraceptives in diabetic women: metabolic effects of four compounds with different estrogen/progestogen profiles.
Women with diabetes need safe, effective contraception. Although intrauterine devices provide superior contraception, concerns remain that progestin absorbed systemically from the levonorgestrel-releasing device may impair carbohydrate metabolism. To examine the effect of the levonorgestrel-releasing intrauterine system on glucose metabolism in diabetic women.
                We randomly assigned 62 women with uncomplicated insulin-dependent diabetes mellitus to either a levonorgestrel-releasing or a copper T 380A intrauterine device. The primary outcome to assess glucose metabolism was glycosylated hemoglobin; fasting serum-glucose levels and daily insulin dose requirements over 12 months of observation were examined as well.
                Outcome data were available for 29 women using the levonorgestrel-releasing and 30 using the copper device. At 12 months, mean glycosylated levels were similar for women of the 2 groups (6.3%, standard deviation [SD] +/- 1.5 compared with 6.3%, SD +/- 1.3, respectively). The same was true for mean fasting-serum glucose levels (7.4 mM, SD +/- 4.2 compared with 7.5 mM, SD +/- 4.2) and daily insulin doses (35.1 units, SD +/- 12.8 compared with 36.4 units, SD +/- 9.0). No important differences were noted at either 6 weeks or 6 months.
                The levonorgestrel-releasing device had no adverse effect on glucose metabolism, even at the 6-week observation when systemic levels of levonorgestrel would have been higher than at later observations. Concern about a potential adverse effect of this contraceptive on glucose control is unwarranted, and its use in women with diabetes should be liberalized.
                I. To assess the effect of combined oral contraceptives (COCs) and intrauterine devices (IUDs) on carbohydrate and lipid metabolism and hemostasis in perimenopausal diabetic women.
                The open randomized study included a total of 113 diabetic women using COCs with different estrogen/progestogen profiles - ethinylestradiol (EE) 20 microg/desogestrel 150 microg, EE 30 microg/desogestrel 150 microg and EE 30 microg/gestodene 75 microg - and levonorgestrel-releasing or copper IUDs. Average daily insulin requirements, levels of glycosylated hemoglobin, total cholesterol, triglycerides, low-density lipoprotein cholesterol and high-density lipoprotein cholesterol, the state of coagulation hemostatis and fibrinolytic activity were determined at baseline and after 3, 6, 9 and 12 months of contraception. The control group was composed of 40 age-matched diabetic women who did not use any methods of contraception.
                Neither COCs nor IUDs influenced glycosylated hemoglobin and had little or no influence on the elevation in the requirements for insulin preparations. The majority of the preparations did not exert any unfavorable effect on the blood lipid profile. Taking COCs was accompanied by increased intravascular activation of blood platelets and to a lesser degree by alterations in parameters of hemostatic homeostasis. The use of IUDs had a neutral effect on blood coagulation and fibrinolysis systems.
                Comparing lipid levels and hemostatic variables as a function of glycosylated hemoglobin level, we conclude that diabetes control has greater influence on these parameters than the type and dose of steroids involved in the contraceptive devices. Twenty-three young women with insulin-dependent diabetes were randomly allocated to contraceptive treatment with either a progestogen only (Lynestrenol 0.5 mg) (LYN) or a combined oral contraceptive (OC) (ethinyl estradiol 50 micrograms + lynestrenol 2.5 micrograms) (EE + LYN). After six months treatment the medication was withdrawn for at least two months, after which the patients were placed on the other preparation. Diabetes control and serum and high density lipoprotein (HDL) lipids were assessed before and after 1, 3 and 6 months of treatment. Low-dose LYN administration did not alter the insulin requirement, blood glucose or body weight while the combined EE + LYN treatment increased the insulin requirement (p less than 0.01) without altering blood glucose or body weight. Low-dose LYN reduced serum triglycerides (p less than 0.001), serum cholesterol (p less than 0.001) and serum phospholipids (p less than 0.01) without affecting HDL lipids, while EE + LYN gave an inconsistent increase in serum triglycerides (p less than 0.01) but no change in HDL lipids. These findings confirm our earlier results and we conclude that EE + LYN influences diabetes control slightly more (although still not seriously) than the low-dose LYN. It is suggested that insulin-dependent diabetics (in contrast to non-diabetics) are more sensitive to the influence of 19-norprogestogens than to alkylated estrogens, with respect to lipid metabolism. The metabolic effects of four oral contraceptives with different estrogen/progestogen profiles (monophasic nonalkylated estrogen/norethindrone, low-dose monophasic ethinyl estradiol (EE2)/norethindrone, progestogen only treatment with norethindrone, and triphasic EE2/levonorgestrel) were examined in insulin-dependent diabetic women. During the 6-month study period, no differences were found in fasting plasma glucose, 24-hour insulin requirements, glycated hemoglobin, free fatty acids, low-density lipoprotein cholesterol concentrations, or high-density lipoprotein cholesterol/total cholesterol ratio between the patients in each treatment group. Compared with the nonalkylated estrogen/norethindrone and the triphasic EE2/levonorgestrel formulations, the low-dose EE2/norethindrone combination resulted in small but significant increases in plasma triglyceride and very low-density lipoprotein cholesterol levels (P less than 0.01), which seemed unfavorable from a clinical point of view. Norethindrone-only treatment appeared to be an appropriate alternative to both the nonalkylated estrogen/norethindrone combination and the triphasic EE2/levonorgestrel formulations.
The four included randomised controlled trials in this systematic review provided insufficient evidence to assess whether progestogen-only and combined contraceptives differ from non-hormonal contraceptives in diabetes control, lipid metabolism and complications. Three of the four studies were of limited methodological quality, sponsored by pharmaceutical companies and described surrogate outcomes. Ideally, an adequately reported, high-quality randomised controlled trial analysing both intermediate outcomes (that is glucose and lipid metabolism) and true clinical endpoints (micro- and macrovascular disease) in users of combined, progestogen-only and non-hormonal contraceptives should be conducted. However, due to the low incidence of micro- and macrovascular disease and accordingly the large sample size and long follow-up period needed to observe differences in risk, a randomised controlled trial might not be the ideal design.