Transdermal hormone therapy and the risk of stroke and venous thrombosis.

Recent case-control and cohort studies have indicated that the transdermal administration of postmenopausal estrogen therapy is not associated with an increased risk of cardiovascular complications, specifically stroke and venous thrombosis. These studies have prompted the clinical promotion of transdermal treatment as 'safer'. There are reasons, however, to be cautious regarding postmenopausal transdermal hormone therapy, especially in regard to stroke. Previous reports linking postmenopausal estrogen therapy and the risk of stroke have not yielded consistent results, finding it difficult to adjust for all confounding factors, including compliance with treatment. Age of the population studies may be a critical issue. Notably, the risk of stroke with oral estrogen was not increased in the Women's Health Initiative when women with prior cardiovascular disease or those older than 60 years were excluded. There does appear to be a dose-response relationship with stroke, similar to that observed with estrogen-progestin contraceptives, and this may be a problem when studying standard doses of transdermal treatment, in that many women receiving transdermal estrogen display lower estrogen blood levels when compared with oral treatment. Clinicians should administer low doses of estrogen to women with risk factors for stroke, and the transdermal route of administration is indicated for women at high risk for venous thrombosis and for older postmenopausal women, especially for women with stroke risk factors. In a recent study, Renoux and colleagues from McGill University in Montreal performed a nested case-control study deriving the data from a cohort of women in the UK General Practice Research Database (GPRD). Current use of oral and transdermal hormone therapy, based on recorded prescriptions, was compared to no use in 15 710 cases and 59 958 controls. The adjusted rate ratio (RR) for stroke for current use of transdermal estrogens, with or without a progestin, was not increased (RR 0.95; 95% confidence interval (CI) 0.75-1.20) compared with a significant increase associated with oral estrogen, with or without a progestin (RR 1.28; 95% CI 1.15-1.42). This would amount to an attributal risk of 0.8 additional strokes per 1000 women per year. There was an indication of a dose-response relationship; a significant increase in risk was observed with transdermal estrogen doses greater than 50 microg. The case-control study by Renoux and colleagues is the first major analysis to compare transdermal and oral hormone therapy and conclude that, compared with an increased risk of stroke with oral therapy, there was no increased risk with transdermal treatment at a dose of 50 microg or less. This report is about as strong an observational study as can be achieved. Large numbers of cases (15 710) and controls (59 958) were available for analysis using the well-known UK GPRD. The use of this computerized database precludes selection bias by the investigators and recall bias by the women in the study. The results support the growing conventional wisdom that transdermal therapy at standard doses is free of the cardiovascular risks associated with oral therapy.

Low-dose hormone therapy in postmenopausal women in China.

OBJECTIVE: To review the experience of menopausal symptoms and low-dose hormone therapy (HT) in postmenopausal women in China. DESIGN: Literature review and critical summaries of available prospective, clinical trials (randomized, controlled trials, RCTs). RESULTS: Chinese women experience menopausal symptoms less frequently compared with women in developed countries, and the prevalence of menopausal symptoms is less in women of southern China than in women of northern China. The majority of postmenopausal Chinese women lack knowledge about HT, and the usage rate of HT is low in these women compared to that in women of developed countries. Some RCTs investigated the efficacy and safety of low- or ultra-low-dose HT, including conjugated equine estrogen, estradiol valerate, transdermal estradiol, nylestriol alone or in combination with progesterone, and tibolone in postmenopausal Chinese women. These RCTs reported that low- or ultra-low-dose HT relieved menopausal symptoms and prevented bone loss as well as standard-dose HT and was less likely to induce side-effects, including irregular vaginal bleeding and breast tenderness; there may be dose-dependent effects of HT. No study evaluated the effects of low-dose HT on cardiovascular events or breast mammographic density/risk of breast cancer. CONCLUSIONS: More RCTs are required to confirm efficacy and to assess the safety of low- or ultra-low-dose HT for a long-term period in a large group of postmenopausal women.

The effect of chronic sodium loading and sodium restriction on plasma prostaglandin A, E, and F concentrations in normal humans.

It has been suggested that prostaglandins may be involved in the control of sodium homeostasis. Prostaglandin A and prostaglandin E have been shown to increase renal blood flow and urinary sodium excretion and prostaglandin A has been shown to stimulate aldosterone release. The purpose of this study was to determine the effect of chronic sodium loading and sodium restriction on plasma prostaglandin A, E, and F concentrations. SEVEN NORMAL HUMAN VOLUNTEERS WERE PLACED ON THREE SODIUM INTAKE DIETS: (a) ad lib. sodium intake, (b) high sodium intake, and (c) low sodium intake. Plasma prostaglandin A, E, and F concentrations were measured by radioimmunoassay. Mean prostaglandin A levels on the ad lib. diet were 1.60 ng/ml. Prostaglandin A levels decreased 49% to 0.82 ng/ml on the high sodium intake and increased 34% to 2.14 ng/ml on the low sodium intake. Prostaglandin A levels increased 161% on the low sodium diet in comparison with levels on the high sodium diet. Plasma prostaglandin E and F concentrations did not change significantly during variation in sodium intake. These results show that dietary sodium content markedly effects plasma prostaglandin A levels and that prostaglandins may play a role in the physiologic mechanism of sodium homeostasis.

Tibolone: clinical recommendations and practical guidelines. A report of the International Tibolone Consensus Group.

An international multidisciplinary panel of experts in the management of the menopause met at the 4th Amsterdam Menopause Symposium in October 2004 to determine the specific place of tibolone, a synthetic steroid with a unique clinical profile, within the wide range of currently available postmenopausal therapy options. The consensus was that tibolone is a valuable treatment option for women with climacteric complaints. As well as relieving vasomotor symptoms, tibolone has positive effects on sexual well-being and mood, and improves vaginal atrophy and urogenital symptoms. Prevention of bone loss with tibolone is comparable to that seen with estrogen therapy (ET) and estrogen/progestogen therapy (EPT). As tibolone rarely causes endometrial proliferation, no additional progestogen is required. It also has good tolerability, being associated with a low incidence of vaginal bleeding and of breast pain. Tibolone does not increase mammographic density. Absolute numbers of women at increased risk for breast cancer are estimated to be low or absent with both tibolone and ET, and the risk with tibolone should be significantly lower than that with EPT. Tibolone might therefore be preferable to EPT in certain women who have not been hysterectomised. Based on the evidence available, the panel proposed a number of subgroups of postmenopausal women with vasomotor symptoms in whom tibolone might have added value; these included women with sexual dysfunction, mood disorders, fibroids and urogenital complaints, as well as those with breast tenderness or high mammographic breast density with EPT use.

Practical guidelines for postmenopausal hormone therapy.

The fourth Amsterdam Menopause Symposium (2-4 October 2004) was dedicated to practical recommendations to guide clinicians after the confusion, concerns, and controversies generated by study results over the previous several years. Those recommendations are summarized in this deliberately concise and user-friendly document, always recognizing that each clinician must help women with their decision-making according to individual needs, desires, and understanding of benefits and risks.

Therapeutic controversy: The safety of third-generation oral contraceptives.

PIP: This paper presents the contributions of Drs. Barbieri, Speroff, Walker, and McPherson to the debate on the safety of third-generation oral contraceptives (OCs). In the overview by Barbieri, the issues of how to assess the quality of the evidence and developing a meaningful framework for integrating an analysis of the benefits and risks of a contraceptive hormone are discussed. He also reflects on the leadership role the endocrinologist must assume in better defining the pharmaco-endocrinology of gestodene and desogestrel. Speroff concludes that modern low-dose OCs are very safe. It was noted that the use of OCs yields an overall improvement in individual health, and from a public health point of view the collection of effects associated with OCs leads to a decrease in the cost of health care. In contrast, Walker argues that low-estrogen OCs containing desogestrel and gestodene carry a modestly elevated risk of venous thromboembolism in comparison to other low-estrogen OCs in widespread use. This statement is supported by McPherson, who emphasizes that the risk associated with OCs is real and should be avoided.^ieng

Estradiol and hemodynamics during ovulation induction.

Left ventricular size and stroke volume increase in human pregnancy and during estrogen administration in laboratory animals. In order to determine if elevated levels of endogenous estrogens in humans produce hemodynamic changes similar to those that occur during pregnancy, 14 patients were studied during ovulation induction at day 8 +/- 2 (SD) (proliferative phase) and at day 14 +/- 4 (midcycle) of their cycles. M-mode echocardiography was carried out with the patient in the left lateral decubitus, head down and head up positions. The mean serum estradiol level was 294 +/- 234 (SD) pg ml-1 at day 8 +/- 2 (treatment day) and it increased to 1503 +/- 531 pg ml-1 at day 14 +/- 4 (cycle day) of the same cycle. This change in serum estradiol was significant (P less than 0.001), associated with an increase in left ventricle diastolic dimension of 2.3 +/- 1.1 mm (P less than 0.001). During the same time period stroke volume and cardiac index correspondingly increased. Heart rate, fractional shortening, and blood pressure did not change and systemic vascular resistance decreased. Many of the cardiovascular adaptations of pregnancy are duplicated by high levels of endogenous estrogens and these changes are evident in as few as 6 days. Thus, we conclude that changes in endogenous estrogen correlate with certain cardiovascular parameters, the most striking of which is the left ventricular size. This may be one of the adaptive mechanisms by which the maternal circulation adapts to pregnancy.

Hormone levels during prostaglandin F 2 infusions for therapeutic abortion.

PIP: This study determines the effect of prostaglandins (PGs) on fetal-placental hormone production or luteal steroidogenesis early in pregnancy by measuring plasma levels of unconjugated estrone, 17-beta estradiol, estriol, progesterone, 17-hydroxyprogesterone, human chorionic gonadotropin (HCG), and human chorionic somatomammotropin (HCS) in 7 healthy women aged 15-30 years receiving PGF2alpha for therapeutic abortion. The patients were 7-20 weeks pregnant and were all from the Clinical Research Unit of the Yale-New Haven Hospital. 5 patients participated in a dose-response tolerance study in which the drug was given over a 12-hour period at predetermined dose levels from 25-200 mcg/minute. The remaining 2 patients received 50 mcg for 12 consecutive hours, and 2 6-hour periods respectively. Heparinized blood samples were collected prior to the beginning of the infusion, at least hourly during the infusion, and also 24 hours after the beginning of the study. Transabdominal and transcervical catheters were used to monitor intrauterine pressures. A definite decline in estradiol levels (from 50-70% of initial levels) was observed during the PGF2alpha infusions. Plasma levels of unconjugated estriol were found to decline earlier and more markedly than the estradiol levels. 17-hydroxyprogesterone was undetectable in all but 1 patient who was 7 weeks pregnant. There were no significant changes in HCG levels in 4 patients until abortion and or curettage was performed. HCS levels gradually declined in 3 patients during the infusion process. This study shows that PGF2alpha does not exert a luteolytic effect in terminating pregnancy from 7-20 weeks gestation, confirming the study of Wiqvist et.al. Further study of the 1st few weeks of gestation should be done before ruling out the possibility of luteolysis in humans.^ieng

The effect of aspirin and indomethacin on the TRH response in man.

A double-blind study of the effect of two inhibitors of prostaglandin synthesis on the TRH stimulation of serum TSH and prolactin was carried out in 35 normal males. The subjects were evaluated before and after the administration of indomethacin or aspirin for one week. Both indomethacin and aspirin lowered plasma prostaglandin E and F levels significantly. Indomethacin treatment had no effect on the serum TSH or prolactin response to 100 mug TRH or the serum T3 and T4 levels. In contrast, aspirin treatment significantly decreased the serum TSH response to TRH and significantly lowered mean total serum T3 (RIA) and T4 (D). There was no effect on the prolactin response to TRH. These findings suggest that aspirin blocks TRH responsiveness by a mechanism other than the inhibition of prostaglandin synthesis, probably by its previously demonstrated effect on increasing the fraction of unbound thyroid hormone.

Cardiac prostaglandin release during myocardial ischemia induced by atrial pacing in patients with coronary artery disease.

The relation between myocardial release of prostaglandin and myocardial ischemia was studied in 12 selected patients with multivessel coronary artery disease. These 12 were chosen for analysis because they experienced angina pectoris, ischemic electrocardiographic changes and decreased myocardial lactate uptake during atrial pacing. Simultaneous aortic and coronary sinus blood samples were obtained at rest, during angina and after recovery and were assayed for prostaglandins F, E and A with radioimmunoassay. Cardiac release of prostaglandin F was observed during angina in 11 of 12 patients. Aortic prostaglandin levels remained constant throught each study. During angina, the mean aortovenous difference (+/- standard error) was -0.30 +/- 0.04 ng/ml (P less than 0.001) for prostaglandin F and -0.10 +/- 0.03 ng/ml (Pless than 0.001) for prostaglandin E. There was no significant release of prostaglandin A. Blood samples were also drawn at subanginal heart rates in two patients. Prostaglandin F was released only during angina. In three control patients with a chest pain syndrome and normal coronary arteries, comparable atrial pacing produced no release of prostaglandin F, E or A. These results, together with the known vascular and metabolic actions of prostaglandins, suggest that these pharmacologically active compounds may also play a physiologic role in the cardiac response to ischemia in man.

The effect of varying low-dose combinations of norethindrone acetate and ethinyl estradiol (femhrt) on the frequency and intensity of vasomotor symptoms.

OBJECTIVE: To determine whether there is a significant reduction in frequency and severity of hot flashes in symptomatic postmenopausal women who are administered continuously different dose combinations of norethindrone acetate and ethinyl estradiol. DESIGN: Two randomized clinical trials (Study 1 and Study 2) were conducted in which study participants recorded in daily diaries the frequency of their hot flashes. Study 2 participants also recorded the number of mild, moderate, or severe hot flashes they experienced. In Study 1, a total of 219 postmenopausal women reporting vasomotor symptoms were placed randomly into groups to receive either a placebo or 1 of 4 treatments (0.2 mg/1 microg; 0.5 mg/2.5 microg; 1 mg/5 microg; or 1 mg/10 microg norethindrone acetate/ethinyl estradiol). In Study 2, a total of 266 highly symptomatic postmenopausal women were placed randomly to receive either a placebo or 1 of 3 treatment groups [0.5 mg/2.5 microg; 1 mg/5 microg; or 1 mg/10 microg norethindrone acetate (NA)/ethinyl estradiol (EE)]. Total duration of treatment was 16 weeks in Study 1 and 12 weeks in Study 2. Study 1 subjects had to have at least 10 hot flashes during the week before randomization. Study 2 subjects had to have at least 56 moderate to severe hot flashes during the week before randomization. RESULTS: In both studies, there was a dose-related decrease in hot flash frequency with the highest dose (1 mg NA/10 microg EE) group that had the greatest response. Significant differences from placebo (p < 0.05, Dunnett's test) occurred within 4 weeks in Study 1 for hot flash frequency with a percent reduction in frequency ranging from 33% for placebo to 84% for both the 1 mg NA/10 microg EE and 1 mg NA/5 microg EE dose groups. Likewise, Study 2 significant reductions in hot flash frequency occurred by Week 2 for 1 mg NA/10 microg EE, Week 3 for 1 mg NA/5 microg EE, and Week 5 for 0.5 mg NA/2.5 microg EE (p < 0.05, Dunnett's test). This dose effect was also apparent with regard to severity. In addition, more subjects had clinically meaningful reductions in hot flash frequency or elimination as the dose combinations increased. CONCLUSION: There were significant reductions in hot flash frequency and severity with continuous treatment with norethindrone acetate and ethinyl estradiol combinations. The time at which significant reductions were observed, as well as the magnitude of the response, were dose dependent. The opportunity for lower-dose options of a new continuous-combined hormone replacement therapy provides therapeutic flexibility for women who are recently menopausal.

Discussion of session on prostaglandins in female reproductive physiology.

PIP: The effects of prostaglandins (PGs) on the ovary are contradictory; in vivo studies with PGF2alpha have shown evident luteolytic effects, while in vitro studies have shown that PGs are usually steroidogenic. It is difficult to reconcile these differences, and a clearer understanding of the mechanism of action of PGs is needed. How PGs work in the induction of labor or for abortion is not very clear. The most simple explanation would indicate a direct muscle stimulating effect. While there is evidence that plasma progestin and estrogen levels are unchanged during PG infusion during delivery at term, there is some suggestion that the mechanism in early pregnancy may be related to an effect on the corpus luteum. Initial studies indicate that plasma progestin level during PG infusion for the induction of abortion does not change until after passage of the placenta; on the other hand it has been found that plasma estrogen levels consistently drop during infusion, especially with high doses of PGs. Also, it is doubtful whether PGs induce oxytocin secretion or enhance the effect of endogenous or administered oxytocin. PGs will induce labor, but it is still not known whether there are any advantages over oxytocic preparations in terms of efficiency. There are 3 major areas of investigation on PGs which require a concentrated effort: 1) the development of a sensitive and specific assay which would allow the measurement of endogenous levels of PGs, 2) clearer ideas about doses and systems of delivery, and 3) the safety level of the drug.^ieng

Postmenopausal hormone therapy and breast cancer.

Given the magnitude of the older female population, the possibility that postmenopausal hormone therapy is associated with an increased risk of breast cancer is an issue of great public and individual importance. Epidemiologic evidence indicates the possibility of a slightly increased risk of breast cancer associated with long durations of postmenopausal estrogen use. However, in a review of the literature, it is apparent that the epidemiologic data are contradictory and do not yield uniform and consistent results. It is further apparent that adding a progestin to a postmenopausal hormone program does not alter the findings compared with the use of estrogen alone. Reasons for this disagreement and lack of definitive evidence are detailed, and it is suggested that any impact of postmenopausal hormone therapy on the risk of breast cancer is unlikely to be great. Finally, the question of whether a woman who has had breast cancer should use postmenopausal hormones is addressed.

Evaluation of a new generation of oral contraceptives. The Advisory Board for the New Progestins.

OBJECTIVE: To assess the differences and similarities in efficacy, safety, and metabolic effects of oral contraceptives (OCs) containing the new progestins desogestrel, gestodene, and norgestimate. All formulations reviewed contained no more than 35 micrograms ethinyl estradiol. DATA SOURCES: Data were reported from approximately 100 published reports, dating from 1980, of comparative and noncomparative clinical studies on phasic and fixed-dose preparations culled from computer searches of several sources, including MEDLINE and Excerpta Medica. METHODS OF STUDY SELECTION: An attempt was made to select the most meaningful studies in terms of length, size, methodology, and quality of description. All clinical studies were considered; in general, review articles were not. Some preclinical studies were also included. No abstracts were used. DATA EXTRACTION AND SYNTHESIS: The indices chosen for examination were contraceptive efficacy, cycle control, coagulation, carbohydrate and lipid metabolism, and androgenicity. CONCLUSIONS: The new formulations were found to be comparable in efficacy to each other and to established agents. They also appeared to be less androgenic than current OCs and to have less impact on carbohydrate and lipoprotein metabolism. Cycle control was similar to that of older products. Changes in coagulation-promoting and antithrombotic factors were minor. Clinical relevance of the results could not be determined because of small sample size and methodologic differences between studies.

Vaginal bleeding in postmenopausal women taking low-dose norethindrone acetate and ethinyl estradiol combinations. The FemHRT Study Investigators.

OBJECTIVE: To determine the effect of continuous combined treatment with norethindrone acetate and ethinyl estradiol (E2) on vaginal bleeding, spotting, or bleeding and/or spotting in postmenopausal women. METHODS: Two randomized clinical trials were conducted in which participants recorded information on the daily occurrence of vaginal bleeding or spotting. In study 1, 219 postmenopausal women reporting at least ten hot flushes per week were randomized to placebo or one of four treatment groups (0.2 mg norethindrone acetate/1 microg ethinyl E2, 0.5 mg norethindrone acetate/2.5 microg ethinyl E2, 1 mg norethindrone acetate/5 microg ethinyl E2, or 1 mg norethindrone acetate/10 microg ethinyl E2). In study 2, 266 postmenopausal women reporting at least 56 moderate to severe hot flushes were randomized to placebo or one of three treatment groups (0.5 mg norethindrone acetate/2.5 microg ethinyl E2, 1 mg norethindrone acetate/5 microg ethinyl E2, or 1 mg norethindrone acetate/10 microg ethinyl E2). The total duration of treatment was 16 weeks in study 1 and 12 weeks in study 2. In both studies, subjects reported in daily diaries whether they had either bleeding or spotting. RESULTS: In study 1, there was a significantly greater relative risk (RR) for bleeding in the group receiving 1 mg norethindrone acetate/10 microg ethinyl E2 at study weeks 4 and 8 (RR = 1.36 and 95% confidence interval [CI] 1.01, 1.83; RR = 1.37 and 95% CI 1.1, 1.72; respectively) compared with placebo, but not at study weeks 12 or 16. The group receiving 1 mg norethindrone acetate/5 microg ethinyl E2 also had a significantly greater risk at weeks 4 and 8 (RR = 1.5 and 95% CI 1.15, 1.96; RR = 1.33 and 95% CI 1.00, 1.77; respectively), whereas the other dose combinations did not differ from placebo. Results from study 2 were similar to those of study 1. CONCLUSION: Although there was a greater risk for bleeding and/or spotting at the higher doses of norethindrone acetate and ethinyl E2, this risk declined over time. If compliance with hormone replacement therapy regimens is influenced at least in part by vaginal bleeding, the combined norethindrone acetate/ethinyl E2 regimen investigated in these studies may provide a treatment option.

A comparison of esterified estrogens with and without methyltestosterone: effects on endometrial histology and serum lipoproteins in postmenopausal women.

OBJECTIVE: To compare the efficacy and safety of esterified estrogens with and without methyltestosterone. METHODS: Twenty-six women participated in a double-blind randomized trial for 6 months. Outcome measures included serum total and lipoprotein-bound cholesterol, vasomotor symptoms, vaginal cytology and endometrial histology, and chemistry values. Analysis of variance and t test statistics were used to assess differences. RESULTS: After 6 months of therapy, the treatment groups were comparable with regard to symptom scores, vaginal cytology and endometrial histology scores, and clinical laboratory test values. Treatment with esterified estrogens plus methyltestosterone significantly decreased total cholesterol, high-density lipoprotein cholesterol (HDL), HDL2, HDL3, and apolipoprotein A1 compared to esterified estrogens alone. CONCLUSIONS: Esterified estrogens with or without methyltestosterone were effective at reducing menopausal symptoms and were well tolerated over 6 months of continuous treatment. A significant decrease in cholesterol and apolipoproteins in the estrogen plus methyltestosterone group suggests a potentially adverse impact on the beneficial effect normally imparted by estrogen therapy.

The effect of angiotensin II and indomethacin on uterine artery blood flow in pregnant monkeys.

In experiments performed in anesthetized monkeys in the third trimester of pregnancy, mean maternal arterial blood pressure was continuously monitored, the uterine artery blood flow was measured with an electromagnetic flow probe, and prostaglandin levels were assayed in the uterine venous effluent. After inhibition of prostaglandin systhesis with indomethacin, the mean arterial blood pressure in response to angiotensin II was greater than the response prior to indomethacin treatment, and an increase in uterine artery blood flow was prevented. These findings are consistent with the suggestion that prostaglandins mediate the uterine artery blood flow response to angiotensin II, as well as modifying the maternal systemic blood pressure response.

Ovulation and pregnancy rates with clomiphene citrate.

A review of recent experience with clomiphene citrate at the Yale-New Haven Medical Center yields the following conclusions: 1) Clomiphene citrate administered at high doses (150 mg and 200 mg) is effective in inducing ovulation in women who would otherwise have failed to conceive if treatment were restricted to only lower dosage regimens. 2) Therapy with clomiphene citrate should be initiated with the 50-mg dose. The 100-mg dose should be reserved for those who fail with the lower dose. 3) Children resulting from clomiphene-induced ovulations appear to be developing normally both mentally and physically. Congenital malformations found in children from clomiphene-induced pregnancies are those seen commonly in general obstetric practice resulting in no significant problems for the children. 4) After 3 ovulations with clomiphene citrate approximately 50% of the patients can be expected to conceive. A 50% conception rate after 3 ovulations with clomiphene citrate does not represent a discrepancy between ovulation rates and pregnancy results, for it agrees statistically with the results obtained for the general population.

Plasma estradiol window and urinary estriol glucuronide determinations for monitoring menotropin induction of ovulation.

The plasma estradiol response is maximal 8--10 hours following mentropin injection. To obtain closer control, a menotropin protocol using 5 PM--8 PM injections and 8 AM blood sampling with a plasma estradiol window of 1000--2000 pg/ml was evaluated with simultaneous calibration of a urinary estriol glucuronide radioimmunoassay. One hundred twenty-eight paired urine and plasma samples were assayed in 48 cycles. In 26 cycles with paired samples on the day of human chorionic gonadotropin (hCG) injection, there were no cases of severe hyperstimulation, 2 cases of moderate hyperstimulation, and 11 pregnancies (42% of cycles given hCG). A window of between 40 and 100 micrograms/day of urinary estriol glucuronide corresponded to the 1000--2000 pg/ml plasma estradiol window by regression analysis. The pregnancy and hyperstimulation rates were compared with those observed in protocols previously published. Radioimmunoassay of urinary estriol glucuronide is faster and simpler than radioimmunoassay of plasma estradiol.

Efficacy and local tolerance of a low-dose, 7-day matrix estradiol transdermal system in the treatment of menopausal vasomotor symptoms.

OBJECTIVE: To determine the efficacy and local tolerance of a new matrix transdermal drug-delivery system that delivers 0.02 mg of 17 beta-estradiol (E2) daily for 7 days for the relief of vasomotor symptoms. METHODS: A total of 324 surgically or naturally menopausal women, all with prior hysterectomy and moderate to severe vasomotor symptoms (56-140 hot flushes per week, with episodes of sweating, during a baseline observation period), participated in two independent, 12-week, randomized, double-blind, placebo-controlled studies. After a 4-week, treatment-free period, each woman received a continuous regimen of either one E2 transdermal system, two E2 transdermal systems, or placebo transdermal system(s) applied every week for 12 weeks. Efficacy was measured as reduction in hot flush frequency, determined from subject diaries. To measure local tolerance, skin irritation (erythema and edema) was objectively and systematically evaluated under blue light after removal of the transdermal system(s). Serum E2 and estrone concentrations were determined in one of the studies during baseline and on days 1, 9, 30, 58, 79, and 84. RESULTS: Mean hot flush frequency decreased from 80 hot flushes per week at baseline to approximately 13 hot flushes per week (84% decrease) after 12 weeks of transdermal E2 treatment. Compared with placebo, the decrease in hot flush frequency was significant as early as weeks 2 and 3, and was maintained through the end of the study. Few clinically significant skin reactions occurred, and only nine (3%) of the subjects withdrew because of a skin effect. After initial increase, serum E2 concentrations remained stable throughout the study, achieving values of approximately 20 and 40 pg/mL above baseline for one and two E2 transdermal systems, respectively. CONCLUSION: The E2 transdermal system effectively reduced the frequency of moderate to severe vasomotor symptoms as early as the second week of therapy and was very well tolerated. The decrease in hot flush frequency was similar to that reported for oral and other transdermal estrogens, but at lower serum E2 concentrations. This result may be due to the stable E2 blood level achieved with this transdermal system.