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At least 19 recordsLinked to original sources
PubMed1992

Free levonorgestrel index and its relationship with luteal activity during long-term use of Norplant implants.

Levonorgestrel serum levels and sex hormone binding globulin (SHBG) were measured in 82 women during different years of use of Norplant implants. The ratio between levonorgestrel and SHBG was calculated as an indicator of the free biologically active fraction of levonorgestrel (free levonorgestrel index, FLI). These parameters were then correlated with the presence of luteal activity, as determined by progesterone levels above 9.6 nmol/L, in a sampling run of 10 samples taken twice a week for five consecutive weeks. Levonorgestrel serum levels remained constant around 1.0 nmol/L during the five-year period. SHBG levels were below normal for the first 18 months of use, returning to normal levels during the last three years of use. The FLI in the first two years was significantly higher than that observed in the later years. The frequency of cycles with luteal activity was 12% during the first 2 years, increasing to 44% in the latter years, when FLI levels were lower. Our results suggest that the changes in SHBG and consequently in the free biologically active fraction of levonorgestrel may largely account for the differences in degree of ovarian suppression observed between the first two years of use of Norplant implants and the latter three, even in the absence of a significant variation in total levonorgestrel concentrations.

Drug Implants↗
PubMed1979

The effect of cyclical administration of levonorgestrel and ethinyloestradiol on blood pressure, body mass, blood glucose and serum triglycerides.

The effects of two differing dosage schedules of ethinyloestradiol and levonorgestrel, taken cyclically as oral contraceptives, on blood pressure, body mass, blood glucose and serum triglycerides were measured. After 12 months there were no significant changes in systolic and diastolic blood pressure or blood glucose levels. There was a small but statistically significant increase in body mass after 1 year in the group taking levonorgestrel 15 microgram and ethinyloestradiol 30 microgram (P < 0,02), but not in the other group, although the mass in this group was significantly increased after 3 months of therapy. There was a statistically significant increase in serum triglycerides in the group taking levonorgestrel 50 microgram with ethinyloestradiol 50 microgram for 11 days, followed by levonorgestrel 125 microgram for 11 days, followed by levonorgestrel 125 microgram with ethinyloestradiol 50 microgram for 10 days. This effect appears to be dose-related and progressive with continued therapy; the significance of these results is discussed.

Adolescent↗
PubMed1979

Plasma lipids and high density lipoproteins during oral contraception with different combinations of ethinyl estradiol and levonorgestrel.

Seventy-five menstruating women seeking contraceptive advice were randomly allocated to treatment with combined oral contraceptives containing either ethinyl estradiol 50 micrograms + levonorgestrel 250 micrograms (50/250), ethinyl estradiol 30 micrograms + levonorgestrel 150 micrograms (30/150) or ethinyl estradiol 50 micrograms + levonorgestrel 125 micrograms (50/125). The concentrations of cholesterol, triglycerides, phospholipids, high density lipoprotein (HDL)-cholesterol and HDL-phospholipids were determined after one, three and six months and compared to the mean of two determinations of the same parameters before medication. Triglycerides increased by 18--42 per cent after 1--6 months of treatment with 50/125. The HDL-cholesterol and HDL-phospholipids were reduced by 10 per cent during 50/250 treatment. No other parameters showed any consistent alteration in any of the treatment groups. Raised triglyceride concentration and/or decreased HDL concentration increases the risk for cardiovascular disease. It is therefore suggested that in order not to alter the HDL concentration a combined oral contraceptive agent should not contain more gestagen-androgen than corresponding to 125--150 micrograms of levonorgestrel. To avoid a rise of the triglyceride level the weight relation between levonorgestrel and ethinyl estradiol should be about 5:1.

Adult↗
PubMed1979

Effects of three different combinations of ethinyl estradiol and levonorgestrel on plasma lipids and high density lipoproteins.

Seventy-five menstruating women seeking contraceptive advice were randomly allocated to treatment with combined oral contraceptives containing either ethinyl estradiol 30 micrograms + levonorgestrel 150 micrograms (30/150), ethinyl estradiol 50 micrograms + levonorgestrel 125 micrograms (50/125) or ethinyl estradiol 50 micrograms + levonorgestrel 250 micrograms (50/250). The concentrations of cholesterol, phospholipids, high density lipoprotein (HDL)-cholesterol, HDL-phospholipids and triglycerides were determined prior to treatment and after one, three and six months of medication. Triglycerides increased by 18--42 per cent after one to six months of treatment with 50/125. The HDL-cholesterol and HDL-phospholipids were reduced by 10 per cent during 50/250 medication. No other parameters showed any consistent alteration in any of the treatment groups. Raised triglyceride concentration and/or decreased HDL concentration may increase the risk for cardiovascular disease. It is therefore suggested that in order not to alter the HDL concentration a combined oral contraceptive agent should probably not contain more 19-nortestosterone type of progestogen than corresponding to 125--150 micrograms of levonorgestrel. To avoid a rise of the triglyceride level the weight relation between levonorgestrel and ethinyl estradiol should be about 5:1.

Cholesterol↗
PubMed1979

First year clinical experience with six levonorgestrel rods as subdermal contraception.

Previous clinical experience with six levonorgestrel subdermal capsules showed a very good contraceptive effectiveness and continuation rate, but with a high proportion of bleeding disturbances, particularly of increased bleeding. It was hypothesized that bleeding could be reduced by higher plasma levels of the steroid, using subdermal rods instead of capsules, as rods have been shown to have a release rate 3 or 4 times that of the capsules. Fifty volunteers were enrolled in a study of the clinical performance of 6 subdermal levonorgestrel rods. Results were compared with a previous experience with 100 volunteers who wore 6 levonorgestrel capsules for a year in the same clinic. Requirement for volunteers to enter the study were the same for capsules and rods. The proportion of women wearing 6 subdermal rods who had increased bleeding was about one half as for the women using 6 levonorgestrel capsules. On the other hand, women using rods had about twice the incidence of amenhorrea, and about four times more hypomenorrhea (4 days or less of bleeding in a 90-day period). There were no pregnancies among the rod users and the discontinuation rate for medical reasons was not higher than for capsule users in the same clinic.

Adolescent↗
PubMedDate not supplied

Reference period analysis of vaginal bleeding with triphasic oral contraceptive agents containing norethindrone or levonorgestrel: a comparison study.

The World Health Organization recommends the use of fixed reference periods for quantification of the incidence and severity of vaginal bleeding when patients use various forms of contraception. Ninety- and 110-day reference periods were used in the analysis of data from daily menstrual diaries kept by 72 healthy women in a one-year study of oral contraceptive agents containing ethinyl estradiol and either norethindrone or levonorgestrel. Analysis of bleeding patterns reported during both 90-day and 110-day periods revealed fewer days of bleeding and/or spotting overall with norethindrone than with levonorgestrel (e.g., a mean of 16.06 vs. 19.55 days, respectively, over the first 90-day period; P = .013) and significantly shorter bleeding and/or spotting episodes with the norethindrone preparation. This trend persisted when data were adjusted for a day-1 pill start. Using either method of analysis, duration of bleeding episodes was shorter among subjects taking norethindrone than levonorgestrel. Pills were missed in both study groups, but more women in the LNG/EE group missed from 1 to 3 pills in at least one cycle (31 vs. 21 in the NET/EE group). The between-group difference in bleeding events may be due to intrinsic hormonal differences in regimens or to the greater number of pills missed among levonorgestrel users.

Adult↗
PubMed1992

A comparison study of lipid and androgen metabolism with triphasic oral contraceptive formulations containing norgestimate or levonorgestrel.

The effects of norgestimate triphasic (Ortho Tri-Cyclen, Tri-Ciles) and levonorgestrel triphasic (Triphasi) formulations on lipid and androgen metabolism were assessed in a study of 66 healthy women treated through six menstrual cycles. Levels of the following were measured: cholesterol and its subfractions, triglycerides, carrier lipoproteins, estradiol, testosterone, and sex hormone binding globulin (SHBG). Comparison of baseline values with values after 3 and 6 months of treatment indicated that both regimens influenced lipid and androgen metabolism. There was a statistically significant between-regimen difference in levels of high-density lipoprotein, which were favorably increased with norgestimate triphasic but reduced with levonorgestrel triphasic. Related data on SHBG showed that plasma levels of this marker of estrogen/androgen balance were increased significantly more in the norgestimate triphasic group, providing additional evidence of low androgenicity. Both regimens inhibited follicular growth to the same extent, as evidenced by low mean levels of estradiol in all on-therapy cycles; and both decreased free testosterone. Side effects in both groups were minor and characteristic of those observed with low-dose oral contraceptive agents. The results of the study support the reported safety and positive effects of norgestimate on lipid and androgen metabolism, in comparison with a levonorgestrel-containing combined oral contraceptive.

Adolescent↗
PubMed1979

A three-year clinical trial with levonorgestrel silastic implants.

Silastic implants containing the progestin, levonorgestrel, were tested as long-term contraceptives in 101 women. After three full years of exposure and 2,998 woman-months of use, no pregnancies had occurred. The continuation rates were 87% at 12 months, 79% at 24 months and 66% at 36 months. The most important side effect was excessive or irregular bleeding during the first year. No treatment was offered for this side effect other than vitamins and iron or change of method, with the exception of 3 cases where ethinyl estradiol was used one time for 2 weeks each. Bleeding disturbances led 8 patients to ask for removal of implants. Other side effects were headache, acne and lower abdominal pain. Blood and urine analysis tested 17 different parameters and all but plasma cortisol remained within normal limits throughout the study. A general tendency toward lowered cortisol values was observed and two subjects had more than one value below the normal limit for the population during the study. Glucose tolerance tests during the second year were abnormal in two women with familial diabetes but they returned to normal values spontaneously at the next test. It is concluded that levonorgestrel implants offer effective protection against pregnancy during the first three years of continuous use. Their acceptability and few side effects justify larger trials, especially if treatment of bleeding irregularities is introduced.

Abdomen↗
PubMed1979

Bleeding and ovulation control with use of a small contraceptive vaginal ring releasing levonorgestrel and estradiol.

Levonorgestrel and estradiol releasing contraceptive vaginal rings (CVR) with an outer diameter of 50 mm were used by twenty women. The treatment was given in three-week cycles followed by one treatment-free week. The treatment was planned to cover six cycles. All subjects kept records of bleeding and were controlled clinically in the course of treatment. Three subjects were followed by blood sampling. Plasma levonorgestrel, estradiol, progesterone and gonadotropins were determined. The subjects experienced no difficulties in using the CVR and 90 per cent continued the treatment through the whole experimental period of six months. One subject discontinued after three cycles because of irregular bleedings and one subject after five cycles because of urinary discomfort. Regular bleedings were observed only in three subjects and in nine cases the bleeding started with the CVR in situ during the last days of the three-week treatment period. Breakthrough bleeding occurred in the remaining eight subjects. The subjective side-effects were as follows: weight gain in four subjects, oedema in one subject and urinary discomfort in one subject. Pituitary function was not generally suppressed as judged by plasma gonadotropins. Out of the three subjects studied, two experienced ovulatory plasma progesterone concentrations.

Body Weight↗
PubMed1979

Treatment of rhesus monkeys (Macaca mulatta) with intrauterine devices loaded with levonorgestrel.

The effects of levonorgestrel-loaded plastic intrauterine devices on endometrial morphology were investigated in 15 rhesus monkeys for 14 weeks. The devices were designed to release 25 microgram of the hormone per day and were inserted in the uterus by hysterotomy. Control animals were sham operated or received inert placebo devices. With the levonorgestrel-releasing devices, widespread changes in endometrial morphology were seen. These changes included atrophy of the endometrial mucosal and glandular epithelium and decidualization of the endometrial stroma. With the inert placebo control devices, only minor changes in endometrial morphology were observed.

Animals↗
PubMed1979

Treatment of rhesus monkeys (Macaca mulatta) with intravaginal rings loaded with levonorgestrel.

The effects of levonorgestrel-releasing intravaginal rings were investigated in 15 rhesus monkeys for 52 weeks. The intravaginal rings were designed to provide a sustained release of either three or ten times the human dose level of the hormone. Untreated placebo rings were used as a control. The devices were well retained. After insertion of the vaginal rings, a dose-related decrease in vaginal bleeding was observed. The vaginal microbial flora were assessed qualitatively and semi-quantitatively and although all groups including controls showed some changes in microbial populations, by the end of the study nearly all animals returned to a normal balanced microflora. Terminal studies showed that, at the high dose level, ovulation was suppressed and widespread atrophy of the uterine mucosal and glandular epithelium had occurred. A dose-related increase in mucus within the lumen of the endocervical canal was observed. Focal or diffuse atrophy of the vaginal mucosal epithelium was seen in the majority of levonorgestrel-treated animals.

Animals↗
PubMed1979

Ovulation inhibition with a combined oral contraceptive containing 20 micrograms ethinyl estradiol and 250 micrograms levonorgestrel. Serum levels of the active ingredients and FSH, LH, estradiol 17-beta and progesterone.

In order to investigate the possible ovulation inhibitory effect of a new oral contraceptive containing a combination of 20 micrograms ethinyl estradiol and 250 micrograms levonorgestrel peripheral serum from five healthy women between 17 and 24 years were analysed for FSH, LH, estradiol 17-beta and progesterone. The measurements were carried out during a control cycle before the treatment, during two treatment cycles and during a subsequent control cycle. In addition, serum levels of ethinyl estradiol and norgestrel were determined during the treatment periods. Radioimmunological methods were utilized for all the measurements. In all five women studied there was a complete inhibition of ovulation during treatment as indicated by a lack of mid-cycle LH peaks and by suppression of normal luteal phase levels of progesterone. Four out of the five women showed no biphasic estradiol pattern. During treatment the serum levels of levonorgestrel varied between 1 and 10 nmol/l while the levels of ethinyl estradiol usually were below the limit of detection for the method used (below 85 pmol/l). Post-treatment control cycles revealed a re-establishment of the ovulatory pattern in four of the five subjects.

Adolescent↗
PubMed1992

Effects of oral contraceptives containing oestrogen combined with norethisterone or levonorgestrel on erythrocyte cation transport in normal women.

1. Studies were undertaken in pre-menopausal women to examine the effects of treatment with standard oestrogen-progestogen and progestogen-ony oral contraceptives on erythrocyte Na+,K+ co-transport and Na(+)-Na+ countertransport over 3- and 6-month periods. Concurrent observations were made on other erythrocyte cation transport components, plasma lipid concentrations, plasma renin activity, plasma aldosterone concentration and blood pressure. 2. Na+,K+ co-transport, measured as the ouabain-resistant, frusemide-sensitive component of 86Rb+ influx, and Na(+)-Na+ countertransport, measured as the ouabain-resistant, phloretin-sensitive component of 22Na+ influx, were both increased in women taking, on days 1-21 of their cycle, ethinyloestradiol (30-50 micrograms) combined with norethisterone (1000 micrograms or 500-1000 micrograms) for 3 or 6 months. Neither of these fluxes was increased in a control group of women, or in women treated for the same time periods with ethinyloestradiol combined with levonorgestrel. 3. In a separate study of erythrocyte cation transport (excluding Na(+)-Na+ countertransport), in which women undertook treatment with norethisterone only (350 micrograms/day) for 6 months starting 6 weeks post partum, no changes in Na+,K+ co-transport were observed at 3 or 6 months; there were no changes in cation transport in a corresponding control group. 4. The results of these studies confirm that certain oral contraceptive compounds can alter erythrocyte cation transport, and indicate that norethisterone in higher dose preparations is the component predominantly responsible. The alterations observed could not be explained by a direct link with concurrent changes in plasma triacylglycerol concentrations or in the renin-aldosterone axis and were not closely associated with elevation of blood pressure.

Adolescent↗
PubMed1979

Effect of cyproterone acetate, levonorgestrel and progesterone on adrenal glands and reproductive organs in the beagle bitch.

The effects of short-term (8 weeks) treatment with different doses of cyproterone acetate (CPA), levonorgestrel (LN) and progesterone (PRO) on the adrenal gland, ovary, uterus and vagina were studied in cycle-synchronised beagle bitches (first anoestrus). The same organs from non-treated primiparous beagle bitches at the 6th and 9th weeks of pregnancy were also included. In the animals treated with the highest doses of CPA (4.0 mg/kg/day orally) and PRO (42.5 mg/kg/day subcutaneously), as well as in pregnant bitches (9th week of pregnancy), a decrease in adrenal weight and cortex width and also an apparent loss of cells in the zona fasciculata and zona reticularis were observed. A marked increase in ovarian weight was recorded only in pregnant bitches (6th week of pregnancy). This was reflected by the presence of multiple well-developed corpora lutea. The ovaries of virgin control and progestagen-treated bitches revealed ovarian atrophy. Progestagen treatment caused marked stimulation of the uterus, resulting in dose-related oedematous and hyperplastic changes. Comparable findings were also observed during pregnancy. The vaginal epithelium of the progestagen-treated and pregnant bitches showed marked mucification as compared with control bitches. These structural responses indicate that progestagen treatment stimulates a pseudopregnancy-like condition in the adrenal glands, uterus and vagina of the beagle bitch.

Adrenal Glands↗