Cyclic hormonal replacement therapy after the menopause: transdermal versus oral treatment

Metabolic syndrome in menopause and associated factors: a meta-analysis

OBJECTIVE

Metabolic syndrome (MetS) is a cluster of risk factors for cardiovascular disease and diabetes. Menopause is associated with an increased risk for MetS. The purpose of this meta-analysis is to better understand the relationship between MetS and menopause.

METHODS

MEDLINE and EMBASE were searched for all the associated articles on (1) MetS components in postmenopausal women vs. premenopausal women, (2) comparison of MetS incidence between surgical menopause and natural menopause, (3) the effect of hormone therapy (HT) with 17β-estradiol (E2) compared to conjugated equine estrogen (CEE) on MetS components among postmenopausal women. A meta-analysis was applied by Review Manager 5.3 software.

RESULTS

All comparable indicators were significantly unfavorably changed in postmenopausal women compared to premenopausal women except for high density lipoprotein cholesterol. Women who underwent surgical menopause suffered a 1.51-fold higher risk for MetS compared to those with natural menopause. HT with E2 provided more benefits for levels of triglyceride and diastolic blood, while CEE showed a better effect on both high and low density lipoprotein cholesterol levels.

CONCLUSIONS

Menopause nearly adversely affects all components of MetS, and surgical menopause may lead to a higher incidence of MetS compared to natural menopause. HT with various preparations may have different effects on MetS components. These results may clarify the management of menopause-related MetS in clinical practice.

Effects of non-oral postmenopausal hormone therapy on markers of cardiovascular risk: a systematic review

OBJECTIVE

To review the effects of non-oral administration of postmenopausal hormone therapy (HT) on risk markers for atherosclerotic and venous thromboembolic disease.Non-oral postmenopausal HT appears not to increase venous thromboembolic risk, whereas the effect on coronary heart disease risk is less clear.

DESIGN

Systematic review of literature obtained from MEDLINE, EMBASE, and CENTRAL databases from 1980 until and including April 2006. Terms for "postmenopausal hormone therapy" and for "non-oral administration" were combined in the search.

SETTING

Randomized clinical trials.

PATIENT(S)

Postmenopausal women, both healthy and with established cardiovascular disease or specified cardiovascular risk factors

INTERVENTION(S)

Non-oral HT (e.g., transdermal or intranasal) compared with oral HT or no treatment/placebo.

MAIN OUTCOME MEASURE(S)

Lipoprotein(a), homocysteine, C-reactive protein (CRP), cell adhesion molecules, markers of endothelial dysfunction, coagulation, and fibrinolysis.

RESULT(S)

Seventy-two studies investigating either transdermal or intranasal administration were included. For non-oral HT, decreases in lipoprotein(a), cell adhesion molecules, and factor VII generally were significant, resistance to activated protein C (APCr) was slightly increased, and other markers including CRP and homocysteine did not change. Compared with oral HT, changes in CRP and APCr were smaller, changes in cell adhesion molecules and some fibrinolytic parameters tended to be smaller, whereas changes in other factors including lipoprotein(a) and homocysteine did not differ.

CONCLUSION(S)

Potentially unfavorable changes seen with oral HT on two important markers, CRP and APCr, are substantially smaller with non-oral HT. Non-oral HT has minor effects on the other cardiovascular risk markers studied. Therefore, compared with oral HT, non-oral HT appears be safer with respect to atherosclerotic and venous thromboembolic disease risk.

Pharmaceutical development and clinical effectiveness of a novel gel technology for transdermal drug delivery

Transdermal gels are designed to deliver sustained drug amounts, resulting in systemically consistent levels. They represent an improvement compared with transdermal delivery by patches because they offer more dosage flexibility, less irritation potential and a better cosmetic appearance. Advanced Transdermal Delivery (ATD) gel technology was developed in order to provide enhanced passive skin permeation of various active drugs for the treatment of many conditions, including hypogonadism, female sexual dysfunction, postmenopausal symptoms, overactive bladder and anxiety. The technology consists of a combination of solvent systems and permeation enhancers enabling systemic drug delivery, and is covered by many patents. Pharmaceutical development of formulations based on the technology allowed optimisation of physicochemical parameters (rheological profile, pH) as well as skin permeation properties (type and concentration of permeation enhancers, thermodynamic activity of the drug). This gel technology has demonstrated to be efficient for many drugs, as shown in the preclinical and clinical pharmacokinetic studies presented in this technology evaluation.

Comparison of pharmacokinetic profiles of a 17 beta-estradiol gel 0.6 mg/g (Gelestra) with a transdermal delivery system (Estraderm TTS 50) in postmenopausal women at steady state

OBJECTIVES

to compare the patterns of a 17 beta-estradiol (E(2)) gel containing 0.6 mg/g (1.5 mg E(2) per day, Gelestra); with the transdermal delivery system (Estraderm TTS 50) applied every 3 days over a 14-day period to women in spontaneous or surgical menopause.

METHODS

a single centre, open, randomised, parallel-group study was conducted. A total number of 33 postmenopausal women were enrolled. In 23 of them the menopause occurred spontaneously, while 10 women were bilaterally ovariectomized. Randomly, the subjects were treated with Estraderm TTS 50 (no. 8) or with Gelestra (no. 14). The pharmacokinetic study of the drugs was performed at the seventh, ninth and 14th day in Gelestra treated women and at the first, third and second day in Estraderm TTS 50 treated women. In fact, the seventh, ninth and 14th day of percutaneous treatment corresponds to the first, third and second day of application of the transdermal system application. Blood samples were taken by each subject at baseline and 1, 2, 3, 4, 8, 12 and 24 h after the gel or transdermal system application. In almost all samples the level of E(2) and estrone (E(1)) were evaluated. Statistical analysis was performed by comparing the two groups of treatment. The following parameters were assessed: mean E(2) and E(1) concentrations, E(2) peak serum concentration within interval from 0 to 72 h (C(max)), E(2) trough concentration within interval from 0 to 72 h (C(min)), area under the E(2) time concentration curve in the interval from 0 to 72 h (AUC((0-72))), the average E(2) concentration during the measurement interval, calculated by dividing AUC((0-72)) by 72 h (C(av)), E(1)/E(2) ratio, and percentage fluctuation (%Fluct) which is equal to 100 (C(max)-C(min)/C(max)).

RESULTS

there was no significant difference in E(2) C(av) between the two treatments. However, significant differences in favour to the gel on the first day (first h) and on third day (72nd h) and in favour to the patch at the second day (48th h) were detected. C(max), E(1)/E(2) ratio and AUC((0-72)) were not statistically different, while a significantly higher C(min) for the gel was observed. Furthermore, the 90% confidence interval for AUC((0-72)) ratio (0.83-1.10) was within the commonly applied bioequivalence acceptance range (0.80-1.25). The %Fluct was significantly lower for Gelestra than for Estraderm TTS 50.

CONCLUSIONS

although the mean E(2) and E(1)concentrations, C(max), E(1)/E(2) ratio and the AUC((0-72)) did not differ between the two E(2) treatments, the Gelestra treatment showed a lower day-to-day variation over the three day application, than the Estraderm TTS 50.

Effects of postmenopausal hormone replacement therapy on lipid, lipoprotein, and apolipoprotein (a) concentrations: analysis of studies published from 1974-2000

OBJECTIVE

To establish reference estimates of the effects of different hormone replacement therapy (HRT) regimens on lipid and lipoprotein levels.

DESIGN

Review and pooled analysis of prospective studies published up until the year 2000.

SETTING

Clinical trials centers, hospitals, menopause clinics.

PATIENT(S)

Healthy postmenopausal women.

INTERVENTION(S)

Estrogen alone, estrogen plus progestogen, tibolone, or raloxifene in the treatment of menopausal symptoms.

MAIN OUTCOME MEASURE(S)

Serum high- and low-density lipoprotein (HDL and LDL) cholesterol, total cholesterol, triglycerides, and lipoprotein (a).

RESULT(S)

Two-hundred forty-eight studies provided information on the effects of 42 different HRT regimens. All estrogen alone regimens raised HDL cholesterol and lowered LDL and total cholesterol. Oral estrogens raised triglycerides. Transdermal estradiol 17-beta lowered triglycerides. Progestogens had little effect on estrogen-induced reductions in LDL and total cholesterol. Estrogen-induced increases in HDL and triglycerides were opposed according to type of progestogen, in the order from least to greatest effect: dydrogesterone and medrogestone, progesterone, cyproterone acetate, medroxyprogesterone acetate, transdermal norethindrone acetate, norgestrel, and oral norethindrone acetate. Tibolone decreased HDL cholesterol and triglyceride levels. Raloxifene reduced LDL cholesterol levels. In 41 studies of 20 different formulations, HRT generally lowered lipoprotein (a).

CONCLUSION(S)

Route of estrogen administration and type of progestogen determined differential effects of HRT on lipid and lipoprotein levels. Future work will focus on the interpretation of the clinical significance of these changes.

Effects of norethisterone acetate addition to estradiol in long term HRT

OBJECTIVE

The aim of this study was to evaluate the efficacy and tolerability of hormone replacement therapy (HRT) among postmenopausal women living in the Lund area of Southern Sweden and to analyze treatment effects in different types or routes of HRT administration, as well as to compare with unopposed estrogen therapy.

METHOD

in an ongoing, large population-based, prospective cohort study, this interim analysis included 3900 women. Of them, 693 postmenopausal women were eligible in the present analyses as they continued to use one of the four commercial HRT products for at least 2-3 years, i.e. continuous oral estradiol (E(2)) 2 mg+norethisterone acetate (NETA) 1 mg (CON-O), sequential oral estradiol 2 mg + norethisterone acetate 1 mg (CYC-O), sequential transdermal estradiol 50 microg + norethisterone acetate 250 microg (CYC-TRANS) and estradiol monotherapy. These women completed one generic questionnaire and one specific 'hormonal' questionnaire, as well as a personal interview pertaining to socio-demographics, detailed status of HRT use, and therapeutic efficacy and untoward side-effects by HRT.

RESULTS

comparing the three combined E(2)+NETA groups with E(2) monotherapy, the beneficial effects on sexual desire and emotional well-being were significantly less in the combined groups than in E(2) monotherapy group. There was no significant difference regarding the negative side-effects between the groups. No significant difference was found between CON-O and CYC-O groups either in positive effects or in negative side-effects. A higher prevalence of positive effects was found in CYC-TRANS group than that in CYC-O group, especially in amelioration of sleep and urinary symptoms. Higher odd ratios of negative effects by HRT, such as irregular bleeds, weight gain, food craving and skin disorders were also found in CYC-TRANS group.

CONCLUSION

in long-term HRT administration, the addition of a progestogen in HRT could compromise the beneficial effects of estradiol, particularly, the effects on women's emotional well being and psychosexual functioning. Administration of NETA continuously and sequentially had similar therapeutic efficacy and tolerability. More marked positive effects, such as improving of sleep and urinary symptoms, as well as nuisance side-effects, i.e. irregular bleeds, weight gain, food craving and skin disorders were encountered by the women using sequential transdermal regimen

Efficacy and tolerability of a new 7-day transdermal estradiol patch versus placebo in hysterectomized women with postmenopausal complaints

OBJECTIVES

To investigate the efficacy and tolerability of a continuously applied 7-day-Estradiol patch (Fem7, Merck KGaA, Germany) delivering 50 microg estradiol per day in the treatment of hysterectomized women with postmenopausal complaints compared with placebo.

DESIGN

A multicentre, randomized, double-blind study with an initial screening phase (phase I), a 3-month double-blind placebo-controlled phase (phase II) and a 3-month open follow-up phase (phase III).

METHODS

186 patients were randomized for a 3-cycle placebo-controlled study followed by a 3-cycle open follow-up (total duration; 6 months). The changes in Kupperman Index (primary efficacy variable), hot flushes and urogenital symptom score were studied from baseline to the end of the study. In addition, skin tolerability was assessed and patients were also asked to grade the subjective acceptance of therapy.

RESULTS

A reduction in Kupperman Index was observed in both groups, and at each cycle of the placebo-controlled treatment phase the 7-day-Estradiol patch was superior compared with placebo (last value vs. baseline P = 0.0006). From the second treatment week onwards a distinct difference was noted in the reduction of hot flushes from baseline between the 7-day-Estradiol patch group and the placebo group. The difference between the groups was statistically significant for each cycle and at the end of the controlled treatment phase (mean weekly hot flush reduction at the end of the placebo-controlled treatment phase: -32.5 for the 7-day-Estradiol patch vs. -22.0 for placebo, P = 0.0025). The efficacy of the 7-day-Estradiol patch within the application period did not show any difference between days 1-3 and 4-7. Subjective acceptance of the 7-day-Estradiol patch was good and 72.4% of patients who took active medication throughout the study were willing to consider continuing its use.

CONCLUSIONS

The 7-day-Estradiol patch is well tolerated and provides effective relief of moderate to severe vasomotor symptoms in hysterectomized women, with a rapid onset of action and 7-day duration of therapeutic effect. Although a placebo effect was observed, the 7-day-Estradiol patch significantly reduced hot flushes and other menopausal symptoms throughout the application period.

Long-term influence of different postmenopausal hormone replacement regimens on serum lipids and lipoprotein(a): a randomised study

OBJECTIVE

To assess the influence of three different postmenopausal hormone replacement therapies on levels of serum lipids and lipoprotein(a) [Lp(a)].

DESIGN

Open, randomised, controlled study.

PARTICIPANTS

One hundred and forty healthy, early postmenopausal women.

INTERVENTIONS

The women were randomised to receive continuous 17 beta-oestradiol, either orally (2 mg daily; n = 35) or transdermally (50 micrograms daily; n = 35), plus 10 mg dydrogesterone daily for 14 days of each 28-day cycle; or 2.5 mg tibolone daily (n = 35). Thirty-five untreated women acted as controls.

MAIN OUTCOME MEASURES

Fasting blood samples were analysed at baseline, 6, 12 and 24 months for low-density lipoprotein (LDL)-cholesterol, high-density lipoprotein (HDL)-cholesterol, very low density lipoprotein (VLDL), total cholesterol, triglycerides, lipoprotein(a)[Lp(a)], apolipoproteins A-1, A-2 and B, fibrinogen, and antithrombin factor III.

RESULTS

At 24 months oral oestradiol increased mean HDL cholesterol (7%; 95% CI 1-14), compared with no change in the transdermal group and a decrease of 26.8% in the tibolone group (95% CI 22.9-30.5); oral oestradiol decreased mean LDL cholesterol (11.8%; 95% CI 6.3-19), compared with no change in the tibolone group. Changes in apolipoprotein A-1 and B showed a similar pattern to HDL and LDL cholesterol, respectively. Oral oestradiol increased serum triglycerides (30%; 95% CI 18-42) after 24 months, compared with no change in the tibolone and transdermal oestradiol groups. Tibolone decreased serum Lp(a) by 36.6% after 24 months (95% CI 8.3-56.2), oral oestradiol decreased levels by 29.4% (95% CI 2-51.1), compared with no change in the transdermal oestradiol group.

CONCLUSIONS

Oral and to a lesser extent transdermal oestradiol when sequentially combined with dydrogesterone, showed a beneficial influence on serum lipids regarding the cardiovascular disease risk, which was not seen with tibolone. The significance of Lp(a) levels on cardiovascular disease risk remains to be determined.

Responses of HDL subclasses, Lp(A-I) and Lp(A-I:A-II) levels and lipolytic enzyme activities to continuous oral estrogen-progestin and transdermal estrogen with cyclic progestin regimens in postmenopausal women

Seventy postmenopausal women took part in the study. Subjects received either continuous oral 17 beta-estradiol 2 mg/day combined with norethisterone acetate 1 mg/day (E2/NETA, Kliogest) or transdermal treatment consisting of 28 day cycles with patches delivering 17 beta-estradiol 50 micrograms/day (Estraderm) combined with cyclic medroxyprogesterone acetate 10 mg/day (E2/MPA, Provera), on days 17-28. At baseline the serum lipid and lipoprotein concentrations, composition and concentrations of high density lipoprotein (HDL) subclasses, lipoprotein (Lp)(AI) and Lp(A-I:A-II) levels were comparable in the two groups. In the E2/NETA group, after 12 months hormone replacement therapy (HRT), the HDL2 cholesterol concentration decreased by 17% (P < 0.01) and the HDL3 cholesterol remained unchanged. The concentrations of HDL2b, HDL2a and HDL3a were reduced by 30, 26 and 15%, respectively, P < 0.001, and the cholesterol:triglyceride ratio decreased significantly in all HDL subclasses. Apolipoprotein (apo) A-I concentration decreased by 5% (P < 0.05), but apo A-II, Lp(A-I) and Lp(A-I:A-II) concentrations remained unchanged. In the E2/MPA group the HDL2 and HDL3 cholesterol levels were both reduced by 6% (P < 0.05) and the HDL3a, HDL3b and HDL3c concentrations decreased by 14, 12 and 17% during the E2/MPA phase compared with baseline (P < 0.01). No major changes in the composition of HDL subclasses occurred in the E2 MPA group during treatment. The apo A-I and Lp(A-I) levels were not changed, but apo A-II and Lp(A-I:A-II) concentrations decreased by 8 and 5%, P < 0.001 and P < 0.05, respectively. At 12 months the postheparin plasma hepatic lipase (HL) activity decreased only in the E2/NETA group (by 12%, P < 0.05). The cholesteryl ester transfer protein (CETP) activity was not affected by either HRT regimen. The results of our study show that the 2 HRT regimens have multiple effects on HDL particles and HRT induced changes in HDL are not associated with changes in activities of lipolytic enzymes or CETP.

Effects of estrogen replacement therapy on thrombin generation

The aim of this study was to investigate the hemostatic system in menopausal women before and after three months of treatment with transdermal estradiol (TTS 50, 50 micrograms/die, n = 13) or coniugated equine estrogen (CEE, 0.625 mg/die, n = 9) by evaluating : beta-thromboglobulin, platelet factor 4, factor VIIag, factor VIIc, fibrinopeptide A-FPA-, thrombin-antithrombin-TAT-complexes, antithrombin-AT-activity, protein C, plasma fibrinolytic activity (euglobulin clot lysis time), plasminogen and antiplasmin activity. FPA levels significantly increased during TTS 50 treatment (p < 0.001) while protein C showed a slight but significant decrease in both treatments (TTS 50 p < 0.001, CEE p < 0.05). TAT complexes and AT were found unaltered. Platelet function and fibrinolytic activity did not significantly change. A significant relationship between FPA and estradiol levels, which were significantly increased during. TTS 50 therapy, was found (r = 0.40, p < 0.05). These findings indicate that unopposed estradiol given by transdermal route induces a slight but significant blood clotting activation, which seems strictly related to its biological activity.

New developments in topical estrogen therapy

OBJECTIVE

To review new developments in transdermal E2 therapy in postmenopausal women.

DESIGN

A bibliographic search (Medline) of the medical literature from 1966 through 1995 was used to identify new studies evaluating transdermal E2.

PATIENT(S)

Menopausal and postmenopausal women.

RESULT(S)

Like oral estrogen, transdermal E2 relieves menopausal symptoms, reverses urogenital atrophy, and conserves bone economy. Initial studies have demonstrated beneficial effects of transdermal E2 on cardiovascular function. Quality of life, patient satisfaction, and compliance also improve with transdermal E2. Advances in transdermal delivery continue to emerge, including low-dose systems and patches that maintain serum E2 levels for a full 7-day period.

CONCLUSION(S)

New developments in transdermal administration have the potential to increase the number of postmenopausal women who accept and are compliant with long-term estrogen replacement therapy.

Hormone replacement therapy lowers plasma Lp(a) concentrations. Comparison of cyclic transdermal and continuous estrogen-progestin regimens

To study the responses of serum lipoproteins, apoproteins (apo's), and lipoprotein(a) (Lp[a]) to two frequently used hormone replacement therapies (HRTs), 120 postmenopausal women were randomly allocated to receive either transdermal therapy consisting of 28-day cycles with patches that delivered 17 beta-estradiol (50 micrograms/d) combined with cyclic oral medroxyprogesterone acetate (10 mg/d for 12 days per cycle) or continuous oral 17 beta-estradiol (2 mg/d) together with norethisterone acetate (1 mg/d) for 12 months. Blood samples were taken before and at 6 and 12 months of HRT. Concentrations of serum total, low density lipoprotein (LDL) and high density lipoprotein (HDL) cholesterol decreased by 14% (P < .001), 17% (P < .001), and 9% (P < .001) in the oral HRT group. Respective changes were 5.7% (P < .001), 4.8% (P < .05), and 4.7% (NS) in the transdermal group. Serum triglycerides remained unchanged in the oral group but decreased by 15.7% (P < .001) in the transdermal group. We observed only trivial changes in serum apo B levels. The changes in apo A-I levels paralleled those of HDL cholesterol in the oral HRT group. The concentration of serum Lp(a) decreased by 31% (P < .001) and 16% (P < .001) in the two groups. The combination of progestin and transdermal estrogen was not associated with any further change of Lp(a). The decrement in Lp(a) during therapy was positively associated with baseline Lp(a) levels in both groups (r = .96, P < .001 and r = .88, P < .001). Thus, both HRT regimens were highly effective in lowering elevated Lp(a) levels in postmenopausal women. The divergent responses of LDL and HDL cholesterol in the two HRT groups may influence the potential cardioprotective effects of the two HRT regimens. Prospective trials are needed to define the long-term effects with respect to coronary heart disease risk.

Menorest: technical development and pharmacokinetic profile

Transdermal application of oestradiol enables the use of lower doses than with the oral drug and avoids first-pass metabolism in the liver. First-generation transdermal delivery systems were of reservoir design. Menorest is one of a new generation of patches, in which oestradiol is dispersed in a micronized suspension throughout the adhesive matrix. This design results in a very thin patch with good cosmetic acceptability. Pharmacokinetic studies indicate that Menorest allows transdermal release of oestradiol at a constant and reproducible rate at doses from 25-100 micrograms/day. There is a linear relationship between the dose of oestradiol administered (which is determined by the surface area of the patch) and the plasma concentration of oestradiol. In contrast to the standard reference reservoir patch, Estraderm, Menorest maintains plasma oestradiol concentrations at or above the target level of 40 pg/ml throughout the 84-h dosing interval.

Phasic serum lipid excursions occur during cyclical oral conjugated oestrogens but not during transdermal oestradiol sequentially combined with oral medroxyprogesterone acetate

BACKGROUND AND OBJECTIVE

Recent data indicate that oral medroxyprogesterone acetate (MPA) has limited unfavourable, neutral or even favourable effects on serum lipid fractions when added to oestrogen replacement therapy. The purpose of this study was to evaluate the serum lipid fractions at the beginning and at the end of each phase of a sequentially combined replacement cycle comparing the oral and the transdermal routes of oestrogen administration.

DESIGN

Randomized study with a matched control group. Oral conjugated oestrogens (OCE, 0.625 mg) or transdermal oestradiol (TE 50 micrograms) was taken from day 1 to day 25 and MPA (5 mg) added on days 14 to 25. Serum lipids were evaluated on days 1, 14 and 25 of monthly replacement cycles.

PATIENTS

The early post-menopausal women in the control group (n = 11) and in the treatment groups (OCE/MPA, n = 15; TE/MPA, n = 17) were evaluated every 3 months for 12 months and every 6 months for another 12 months.

MEASUREMENTS

Serum levels of triglycerides (TG), cholesterol (C) fractions and apolipoproteins (Apo) and their respective ratios were measured at months 1, 3, 6, 9, 12, 18, 24. Menopausal symptoms and uterine bleedings were evaluated in parallel and an endometrial biopsy was performed at the end of the 12th and 24th months of treatment.

RESULTS

After 14 days of OCE, C, LDL-C, and Apo B were decreased and TG, HDL-C and Apo A1 were increased. The sequential addition of MPA accentuated the reduction of LDL-C and Apo B but attenuated the elevation of TG, HDL-C and Apo A1. These changes tended to revert toward baseline during the period free of medication. By contrast, at the end of 14 days of TE there was a non-significant reduction in TG and LDL components and a limited increase in HDL-C and Apo A1. During the subsequent addition of MPA there was no significant decrease in TG, LDL-C or Apo B but an elimination of the increase in HDL components. These combined changes resulted in a significant reduction in the LDL-C/HDL-C ratio and a significant elevation in the Apo A1/Apo B ratio only in the OCE/MPA group.

CONCLUSION

Overall, oral conjugated oestrogens induced favourable intragroup changes in cholesterol fractions whereas transdermal oestradiol maintained serum lipids at levels not different from baseline. The sequential addition of oral medroxyprogesterone acetate attenuated the beneficial elevation of HDL, did not affect the beneficial effect of oestrogens on ratios of cholesterol fractions and attenuated the unfavourable effect of oral conjugated oestrogens on triglycerides. The partial loss of beneficial effects on lipoproteins during cyclical interruption of hormone therapy would be an argument in favour of the evaluation of continuous regimens of oestrogen/progestagen replacement.