Monophasic Group Research Articles

A comparative study of the effects of a monophasic and a triphasic oral contraceptive containing ethinyl estradiol and levonorgestrel on lipid and lipoprotein metabolism

A comparative study of the effects of a monophasic and a triphasic oral contraceptive containing ethinylestradiol (EE) and levonorgestrel (LNG) on lipid and lipoprotein metabolism was conducted on 45 Singapore women under the WHO Special Programme of Research in Human Reproduction. The women were randomly allocated to one of the two pill groups — a triphasic preparation containing low doses of LNG and EE in various proportions and a monophasic preparation of 150 μg LNG and 30 μg EE, and an additional 18 women, choosing to use IUDs, were recruited as controls. Blood samples were taken at admission, 3 and 12 months thereafter. For both pill groups, total cholesterol decreased with duration of use, while HDL cholesterol decreased slightly at 3 months and thereafter increased. LDL cholesterol decreased slightly at 3 months, returning to baseline at 12 months for the monophasic group, while remaining unchanged at 12 months for the triphasic group. The monophasic preparation appeared to lower total, LDL and HDL cholesterols to a greater extent at 3 months than the triphasic preparation. Compared with IUD users, for the monophasic group, both total and HDL cholesterols were significantly lower at 3 months and HDL and LDL cholesterols were lower at 12 months. In addition, ratios of HDL cholesterol/LDL cholesterol and HDL cholesterol/total cholesterol were significantly lower at 12 months. Changes in triglycerides were minimal for both pill groups. However, at 3 months, triglycerides for the triphasic group were significantly higher than the IUD users, but this observation was not of any clinical importance since comparison of changes with their respective pretreatment values were not statistically significant. These results indicate that these changes are related to the dosage and estrogen-progestogen ratio of the preparation. Furthermore, the monophasic preparation may have a disadvantage over the triphasic preparation since it appears to cause more disturbance in lipid metabolism. However, it is noted that these changes in lipids and lipoproteins were minimal and did not appear to be of any clinical significance.

Relationship between premenstrual symptoms and oral contraceptive use: a controlled study.

Patterns of menstrual cycle-related change were compared in three groups of women differing in their use of oral contraceptives and being matched for age, occupation, and parity. These groups were: a "monophasic group" (n = 35) established on low dose "combined" pills with stable levels of estrogen and progestagen. a "triphasic group" (n = 30) on low dose pills with escalating progestagen dosage, and a "non-pill control group" (n = 57) using nonsteroidal contraceptives. Each woman kept visual analogue ratings of mood, irritability, energy, tension, breast tenderness, bloating, and sexual interest for two or three cycles. Cyclicity was evident in all variables assessed, but the only variable to show a clear difference between groups was breast tenderness; the "monophasic group" showed less premenstrual breast tenderness than the other two groups. The monophasic group also showed a tendency to menstrual rather than premenstrual symptoms. In view of the similarity of timing of most cyclical symptoms in the three groups, it is difficult to attribute such cyclical phenomena to the effects of either ovulation or variation in corpus luteum function. For most subjects, the cyclical changes were relatively mild, and these findings need to be replicated in women suffering from severe premenstrual syndrome. However, alternative explanations need to account for changes in women both taking and not taking oral contraceptives.

A comparative analysis of three different dose combinations of oral contraceptives

Three different low-dose formulations of oral contraceptives were compared to determine the most suitable preparation for Filipino women as reflected in the first year continuation rates, incidence of side effects and failure rates. A total of 1,800 subjects were enrolled in the study from 18 health centers in six provinces in two regions of the Philippines, covering a total of 18,282 women-months of use. Sociodemographic characteristics were comparable. The monophasic levonorgestrel group showed the best performance followed by the triphasic preparation. The norethindrone group consistently showed higher drop-out rates, which may be due to the relatively higher incidence of side effects. For all three preparations, bleeding irregularities were low. There were no major side effects and no pregnancy was reported in one year of use. Noted was a distinct regional and provincial difference in recruitment and follow-up performance, possibly due to clinic, client or program factors.

Comparative effects of monophasic desogestrel plus ethinyloestradiol and triphasic levonorgestrel plus ethinyloestradiol on lipid metabolism

The effects of the monophasic oral contraceptive preparation desogestrel plus ethinyloestradiol (EE) and triphasic levonorgestrel plus EE on lipid metabolism were compared. Sixteen young healthy female volunteers received monophasic desogestrel plus EE ( 21 × 150 30 ), whereas eighteen women received triphasic levonorgestrel plus EE ( 6 × 50 30 + 5 × 75 40 + 10 × 125 30 ) for six consecutive cycles. The lipid composition of the various lipoprotein fractions was estimated after separation in a density gradient by ultracentrifugation. In addition, the apolipoproteins A-I and B were assessed. HDL-cholesterol (precipitation method), HDL-2 cholesterol, HDL-2 phospholipids and the ratio apolipoprotein A-I to apolipoprotein B were significantly higher in the monophasic desogestrel group than in the triphasic levonorgestrel group after three and six treatment cycles. HDL-cholesterol (gradient), HDL-phospholipids (gradient), HDL-3 phospholipids and apolipoprotein A-I were only significantly higher after six treatment cycles. No differences between the groups were observed for the other lipid variables studied including triglycerides and VLDL-triglycerides.