The effects of norethisterone in postmenopausal women on oestrogen replacement therapy: a model for the premenstrual syndrome

Diagnostic and therapeutic use of oral micronized progesterone in endocrinology

Progesterone is a natural steroid hormone, while progestins are synthetic molecules. In the female reproductive system, progesterone contributes to the control of luteinizing hormone and follicle-stimulating hormone secretion and their pulsatility, via its receptors on the kisspeptin, neurokinin B, and dynorphin neurons in the hypothalamus. Progesterone together with estradiol controls the cyclic changes of proliferation and decidualization of the endometrium; exerts anti-mitogenic actions on endometrial epithelial cells; regulates normal menstrual bleeding; contributes to fertilization and pregnancy maintenance; participates in the onset of labor. In addition, it exerts numerous effects on other endocrine systems. Micronized progesterone (MP) is natural progesterone with increased bioavailability, due to its pharmacotechnical micronized structure, which makes it an attractive diagnostic and therapeutic tool. This critical literature review aims to summarize and put forward the potential diagnostic and therapeutic uses of MP in the field of endocrinology. During reproductive life, MP is used for diagnostic purposes in the evaluation of primary or secondary amenorrhea as a challenge test. Moreover, it can be prescribed to women presenting with amenorrhea or oligomenorrhea for induction of withdrawal bleeding, in order to time blood-sampling for diagnostic purposes in early follicular phase. Therapeutically, MP, alone or combined with estrogens, is a useful tool in various endocrine disorders including primary amenorrhea, abnormal uterine bleeding due to disordered ovulation, luteal phase deficiency, premenstrual syndrome, polycystic ovary syndrome, secondary amenorrhea [functional hypothalamic amenorrhea, premature ovarian insufficiency], perimenopause and menopause. When administrated per os, acting as a neurosteroid directly or through its metabolites, it exerts beneficial effects on brain function such as alleviation of symptoms of anxiety and depression, asw well as of sleep problems, while it improves working memory in peri- and menopausal women. Micronized progesterone preserves full potential of progesterone activity, without presenting many of the side-effects of progestins. Although it has been associated with more frequent drowsiness and dizziness, it can be well tolerated with nocturnal administration. Because of its better safety profile, especially with regard to metabolic ailments, breast cancer risk and veno-thromboembolism risk, MP is the preferred option for individuals with an increased risk of cardiovascular and metabolic diseases and of all-cause mortality.

Norethisterone and its acetate - what's so special about them?

INTRODUCTION

Progestogens (progestins) are widely used for contraception, in postmenopausal hormone therapy, and in treatment of abnormal uterine bleeding and endometriosis. Norethisterone (NET) and its acetate (NETA) differ from other progestogens by their partial conversion to ethinylestradiol (EE). We review their special characteristics and focus on the clinically relevant risk factors associated with estrogen action, such as migraine with aura and risk of thrombosis.

METHODS

Narrative review based on a medical literature (OvidMedline and PubMed) search.

RESULTS

NET converts to significant amounts of EE; 10-20 mg NET corresponds to 20-30 µg EE. The effects of NET on the endometrium are pronounced, making it a good choice for treating abnormal uterine bleeding, endometriosis, and endometrial hyperplasia. NET also has beneficial effects on bone mineral density and positive or neutral effects on cardiovascular health. Conversely, long-term use of NET is associated with a slightly increased breast cancer risk, and the risk of venous thromboembolism is moderately increased. This risk seems to be dose-dependent; contraceptive use carries no risk, but therapeutic doses might be associated with an increased risk. Studies suggest an association between combinations of EE and progestogens and ischaemic stroke, which in particular concerns women with migraine. No studies have, however, assessed this risk related to the therapeutic use of NET.

CONCLUSIONS

NET is a potent progestogen, especially when considering the endometrium. Its partial conversion to EE, however, is important to remember. Clinical consideration is required with women at high risk for either breast cancer or thromboembolism, or experiencing migraine with aura.

Migraine, menopause and hormone replacement therapy

Perimenopause marks a period of increased migraine prevalence in women and many women also report troublesome vasomotor symptoms. Migraine is affected by fluctuating estrogen levels with evidence to support estrogen 'withdrawal' as a trigger of menstrual attacks of migraine without aura, while high estrogen levels can trigger migraine aura. Maintaining a stable estrogen environment with estrogen replacement can benefit estrogen-withdrawal migraine particularly in women who would also benefit from relief of vasomotor symptoms. In contrast to contraceptive doses of ethinylestradiol, migraine aura does not contraindicate use of physiological doses of natural estrogen. In women with migraine with or without aura, using only the lowest doses of transdermal estrogen necessary to control vasomotor symptoms minimizes the risk of unwanted side effects. Cyclical progestogens can have an adverse effect on migraine so continuous progestogens, as provided by the levonorgestrel intrauterine system or in continuous combined transdermal preparation, are preferred. There are no data on the effect of micronized progesterone on migraine, either cyclical or continuous. Non-hormonal options for both conditions are limited but there is evidence of efficacy for escitalopram and venflaxine.

Depression During the Menopausal Transition

The perception that menopause leads to mood disturbances such as depression has a long history. How did these beliefs come about, and are they supported by the scientific literature? This article reviews the theories of menopause and depression, the scientific literature, and the implications of these findings for prevention and treatment. Epidemiologic studies of menopausal status and depression do not provide consistent evidence of an association between the menopausal transition and depression among the general population of women. Depression experienced by women transitioning through menopause may be attributed to factors unrelated to menopause. A subset of women, however, may be more vulnerable to the effects of hormonal changes. For some women, short-term estrogen replacement therapy to relieve vasomotor symptoms may be beneficial, although for others psychotherapy or antidepressants may be more appropriate. Additional research is needed to better understand the association between different stages of the menopausal transition and dysphoric mood or depression, and better identification of women potentially at risk for depression during the menopausal transition.

Hormone therapy for reproductive depression in women

An email survey of patients attending a PMS and Menopause Centre produced 238 patients whose principal presenting symptom was depression. Seventy-seven percent claimed to have had severe or moderate depression, 17% had had at least one psychotic episode and 14% had attempted suicide. Fifty-eight percent had seen a psychiatrist. Seventy-one percent had received antidepressants and 17% had received mood stabilising drugs. Twelve percent had been admitted to a psychiatric hospital and 3.8% had received electroconvulsive therapy. Sixty-eight percent had premenstrual syndrome as a teenager and 145 women (89%) out of 165 women who had been pregnant had no depression during pregnancy but 110 (66%) developed postnatal depression. Ninety-seven women (58%) who had been pregnant had suffered both premenstrual depression and postnatal depression. All were treated with transdermal estrogens and 93% also had transdermal testosterone. One hundred and seventy-one patients had a uterus and received cyclical progestogen to protect the endometrium and 63% of these developed the premenstrual syndrome-type symptoms of progesterone intolerance during the progestogen days. Thirty-five percent of patients claimed to be cured and 55% had a considerable improvement with estrogen therapy. Only 3.7% reported that there was no improvement. For 94%, the hormone therapy was a life-changing event for the better. None were worse. Forty patients had hysterectomy and bilateral oophorectomy for progesterone intolerance or heavy uterine bleeding and 38 replied that it was life changing for the better with less or no depression. It is concluded that premenstrual and postnatal depressions appear in the same vulnerable women. These women are typically well during pregnancy and are a sub group of reproductive depression which also develops climacteric depression in the transition phase. These types of depression are the product of hormonal changes and respond well to transdermal hormone therapy.

Missing and Possible Link between Neuroendocrine Factors, Neuropsychiatric Disorders, and Microglia

Endocrine systems have long been suggested to be one of the important factors in neuropsychiatric disorders, while the underlying mechanisms have not been well understood. Traditionally, neuropsychiatric disorders have been mainly considered the consequence of abnormal conditions in neural circuitry. Beyond the neuronal doctrine, microglia, one of the glial cells with inflammatory/immunological functions in the central nervous system (CNS), have recently been suggested to play important roles in neuropsychiatric disorders. However, the crosstalk between neuroendocrine factors, neuropsychiatric disorders, and microglia has been unsolved. Therefore, we herein introduce and discuss a missing and possible link between these three factors; especially highlighting the following hormones; (1) Hypothalamic-Pituitary-Adrenal (HPA) axis-related hormones such as corticotropin-releasing hormone (CRH) and glucocorticoids, (2) sex-related hormones such as estrogen and progesterone, and (3) oxytocin. A growing body of evidence has suggested that these hormones have a direct effect on microglia. We hypothesize that hormone-induced microglial activation and the following microglia-derived mediators may lead to maladaptive neuronal networks including synaptic dysfunctions, causing neuropsychiatric disorders. Future investigations to clarify the correlation between neuroendocrine factors and microglia may contribute to a novel understanding of the pathophysiology of neuropsychiatric disorders.

Potential strategies to avoid progestogen-induced premenstrual disorders

Non-hormonal approaches to premenstrual syndrome (PMS) treatment such as selective serotonin reuptake inhibitors are by no means effective for all women and frequently we must resort to endocrine therapy. During many of the hormonal approaches, PMS-like symptoms can be introduced or re-introduced during the necessary cyclical or continuous progestogen component of the therapy. This is seen with combined oral contraception, progestogen only contraception, progestogen therapy for heavy menstrual bleeding and endometriosis, sequential hormone replacement therapy and any therapeutic strategy for premenstrual syndrome where it is necessary to provide endometrial protection, including estrogen suppression of ovulation or add-back during gonadotrophin releasing hormone suppression. The link to progestogen is very often missed by health professionals. When the pattern of symptoms mimics the cyclicity of PMS, it is termed progestogen-induced premenstrual disorder. The need to use progestogen to protect the endometrium from the proliferative actions of estrogen can pose insurmountable difficulties in managing premenstrual disorders. In the absence of any really useful evidence, nearly all practice in this area depends on clinician experience. We cannot afford to wait for adequate research evidence to be produced - it never will - and so we must rely on empirical findings, clinical experience, theoretical strategies and common sense.

Neurobiological Underpinnings of the Estrogen - Mood Relationship

Women are at a higher risk than men to develop mood disorders and depression. The increased risk is associated with fluctuating estrogen levels that occur during reproductive cycle events, particularly during the menopausal transition, a time characterized by drastic fluctuations in estrogen levels and increases in new onset and recurrent depression. Conversely, recent data show that hormone therapy, particularly transdermal estradiol formulations, may prevent mood disorders or even serve as a treatment regimen for women with diagnosed mood disturbances via estrogen regulation. While the exact mechanism is unknown, there is compelling scientific evidence indicating the neuromodulatory and neuroprotective effects of estrogen, which are directly relevant to mood symptomotology. Specifically, affective regulation has been linked to neural structures rich in estrogen receptors and estrogenic regulation of neurotransmitters. While a wealth of basic science, observational and clinical research support this rationale, potential mediating variables, such as estrogen formulation, proximity of administration to menopause, and the addition of progestins should be considered. Furthermore, the nature of postmenopausal exogenous hormone formulations in relation to premenopausal endogenous levels, as well as the ratio of estrone to estradiol warrant consideration.

Treatment of premenstrual disorders by suppression of ovulation by transdermal estrogens

The understanding of the cause and treatment of premenstrual disorders is confused but it is essentially the result of cyclical ovarian activity, usually ovulation, and an effective treatment should be by suppressing ovulation. This can be done by an oral contraceptive but as these women are progestogen intolerant the symptoms may persist becoming constant rather than cyclical. Alternatively, transdermal estradiol by patch, gel or implant effectively removes the cyclical hormonal changes, which produce the cyclical symptoms. A shortened seven-day course of a progestogen is required each month for endometrial protection but it can reproduce premenstrual syndrome-type symptoms in these women. Gonadotropin-releasing hormone with ‘add-back’ is effective in the short term. Laparoscopic hysterectomy and bilateral oophorectomy with adequate replacement of estrogen and testosterone should be considered in the severe cases with progestogenic side-effects.

Effect of estrogen replacement therapy on symptoms of depression and anxiety in non-depressive menopausal women: a randomized double-blind, controlled study

The efficacy of estrogen replacement therapy (ERT) for mood disturbances associated with menopause has yet to be firmly established. The objective of this study was to investigate the efficacy of ERT for improving mood and anxiety of non-depressive postmenopausal women. This double-blind, randomized, placebo-controlled study involved two treatment groups: one receiving conjugated equine estrogens (CEEs; 0.625 mg/day) and the other placebo, for six cycles of 28 days each. Subjects were hysterectomized, healthy, non-depressive (according to Schedule for Affective Disorders and Schizophrenia, Life Time Version [SADS-L]) women. Depressive and anxiety symptoms were assessed with the Beck Depression Inventory (BDI), and the Hamilton Anxiety Scale (HAMA), respectively. The Profile of Mood States (POMS) and other scales were used to characterize symptoms. In both groups, BDI scores were significantly lower at cycles 1, 2, 3, and 6, compared with baseline assessments (p<0.01). Anxiety scores for both groups significantly improved from cycle 3 to study endpoint. The only significant difference favoring the active group occurred at cycle 1. POMS scores were significantly improved at the end of cycles 1, 2, 3 and 6 among treated subjects and at the end of cycles 2, 3, and 6 among placebo subjects. ERT is not associated with improvements in mood or anxiety symptoms in non-depressive, hysterectomized, postmenopausal women.

A guide to the treatment of depression in women by estrogens

Premenstrual depression, postnatal depression and climacteric depression are related to changes in ovarian hormone levels and can be effectively treated by hormones. It is unfortunate that psychiatrists have not accepted this form of treatment and this paper is an attempt to simplify this treatment, which should include transdermal estrogens, possibly testosterone and, if the woman has a uterus, also progestogen. A balance is often necessary between these three hormones. Transdermal estrogens in the appropriate dose will suppress ovulation and suppress the cyclical hormonal changes that produce premenstrual depression. Estrogens also have a mood-enhancing effect in postnatal depression and the depression in the transitional phase of the menopause. It is possible to add transdermal testosterone which will improve mood, energy and libido. The problem is the progestogen as these women are often progestogen-intolerant. Progestogen should be used in the lowest dose and for the shortest duration necessary to prevent endometrial hyperplasia or the return of premenstrual syndrome-type symptoms if the women are progestogen-intolerant. The use of estrogens for depression in these women does not exclude the use of antidepressants. Hormone-responsive depression cannot be diagnosed by measuring hormone levels but can only be diagnosed by a careful history relating depression to the menstrual cycle, pregnancies and the perimenopausal years. These appropriate questions should prevent the endocrine condition of premenstrual depression being misdiagnosed as bipolar disorder and the woman given inappropriate treatment.

Progress in the Pharmacotherapy of Menstrual Migraine

Menstrual migraine is a common neurological condition reported to affect up to 60% of women with migraine. Most women manage migraine adequately with symptomatic treatment alone. However, in women with menstrual migraine, menstrual attacks are recognised to be more severe, last longer, and are less responsive to treatment compared with attacks at other times of the menstrual cycle. In these situations, prophylactic treatment may be necessary. Short-term perimenstrual and continuous prophylactic treatments have shown efficacy in clinical trials but none are licensed for menstrual migraine. This article reviews the evidence for acute and prophylactic drugs in the management of this condition and considers future therapeutic options.

Paradoxical effects of GABA-A modulators may explain sex steroid induced negative mood symptoms in some persons

Some women have negative mood symptoms, caused by progestagens in hormonal contraceptives or sequential hormone therapy or by progesterone in the luteal phase of the menstrual cycle, which may be attributed to metabolites acting on the GABA-A receptor. The GABA system is the major inhibitory system in the adult CNS and most positive modulators of the GABA-A receptor (benzodiazepines, barbiturates, alcohol, GABA steroids), induce inhibitory (e.g. anesthetic, sedative, anticonvulsant, anxiolytic) effects. However, some individuals have adverse effects (seizures, increased pain, anxiety, irritability, aggression) upon exposure. Positive GABA-A receptor modulators induce strong paradoxical effects including negative mood in 3%-8% of those exposed, while up to 25% have moderate symptoms. The effect is biphasic: low concentrations induce an adverse anxiogenic effect while higher concentrations decrease this effect and show inhibitory, calming properties. The prevalence of premenstrual dysphoric disorder (PMDD) is also 3%-8% among women in fertile ages, and up to 25% have more moderate symptoms of premenstrual syndrome (PMS). Patients with PMDD have severe luteal phase-related symptoms and show changes in GABA-A receptor sensitivity and GABA concentrations. Findings suggest that negative mood symptoms in women with PMDD are caused by the paradoxical effect of allopregnanolone mediated via the GABA-A receptor, which may be explained by one or more of three hypotheses regarding the paradoxical effect of GABA steroids on behavior: (1) under certain conditions, such as puberty, the relative fraction of certain GABA-A receptor subtypes may be altered, and at those subtypes the GABA steroids may act as negative modulators in contrast to their usual role as positive modulators; (2) in certain brain areas of vulnerable women the transmembrane Cl(-) gradient may be altered by factors such as estrogens that favor excitability; (3) inhibition of inhibitory neurons may promote disinhibition, and hence excitability. This article is part of a Special Issue entitled: Neuroactive Steroids: Focus on Human Brain.

Association between Hardness (Difficulty of Chewing) of the Habitual Diet and Premenstrual Symptoms in Young Japanese Women

Recent evidence suggests that voluntary rhythmic movements such as chewing may increase blood serotonin and subsequently brain serotonin, which in turn acts to alleviate premenstrual symptoms. In this observational cross-sectional study, we tested the hypothesis that hardness (difficulty of chewing) of the habitual diet (i.e. dietary hardness) is associated with decreased premenstrual symptoms. Subjects were 640 female Japanese dietetic students aged 18-22 years. Dietary hardness was assessed as an estimate of masticatory muscle activity for the habitual diet (i.e. the difficulty of chewing the food). The consumption of a total of 107 foods was estimated by means of a self-administered, comprehensive diet history questionnaire, and masticatory muscle activity during the ingestion of these foods was estimated according to published equations. Menstrual cycle symptoms were assessed using the retrospective version of the Moos Menstrual Distress Questionnaire, from which total score and subscale scores (i.e. pain, concentration, behavioral change, autonomic reactions, water retention, and negative affect) in the premenstrual phase were calculated and expressed as percentages relative to those in the intermenstrual phase. Dietary hardness was not associated with total score in the premenstrual phase (P for trend = 0.48). Further, no association was seen for any subscale score in the premenstrual phase (P for trend = 0.18-0.91). In conclusion, this preliminary study failed to substantiate a hypothesized inverse relationship between hardness of the habitual diet and premenstrual symptoms. Considering the plausibility of the putative mechanism, however, further investigation using more relevant measures of chewing and premenstrual symptoms is warranted.

Progesterone, progestins and psychosomatic health of women

Psychosomatics as a medical perspective and discipline focuses on the interaction of physical and mental health in the specific life situation of a patient, taking into account the physical and emotional well-being, role functioning, satisfaction with the partner and family relationship, as well as sexual function and satisfaction. There are two important effects of progesterone on the combined physical, mental and sexual well-being of the climacteric patient. The first is the antiestrogenic effect of progesterone on the peripheral physical level which not only protects the endometrium against overstimulation but also reduces individual suffering from heavy bleeding, breast tension, bloating and general discomfort. The second effect is due to the complex action of progesterone in the brain. Studies using different progestins in different dosages and in different regimens show contradictory results. Some studies demonstrate an increase in depressed mood and reduced well-being while using synthetic progestins. Other studies, however, indicate an anxiolytic and sometimes antidepressant effect of progesterone and progesterone-like progestins with an improvement of emotional well-being and quality of life. In the individual patient, the positive or negative emotional and mental state can be conditioned by various pathways of progesterone and progestins. The antiestrogenic effect can attenuate the psychotropic effect of estradiol (E2) on the brain, thus reducing emotional well-being. Progesterone interacting with many brain areas can have a mood stabilizing and anxiolytic effect through the action on the GABA receptor. This effect seems to be strongest when using natural progesterone and the effect varies considerably among different progestins and different dosages due to metabolic pathways involving the production of allopregnanolone or other metabolites. In conclusion, the positive anxiolytic and sedative effects of progesterone on the central nervous system depend on the type of progestogen, the dosage, the timing of application, the combination with estrogen, etc. Progesterone and progestins have important potential to maintain or improve the psychosomatic health of women. Their use must, however, be tailored to specific symptom clusters and to the individual's pre-existing psychosomatic health status.

A double-blind placebo-controlled study to evaluate the effect of progestelle progesterone cream on postmenopausal women

OBJECTIVE

To evaluate the effect on climacteric symptoms and quality of life, and the safety of four doses of progestelle progesterone cream administered for 24 weeks to postmenopausal women complaining of moderate to severe menopausal symptoms. Design Single-centre, double-blind, randomized, placebo-controlled study. Population Two hundred and twenty-three healthy postmenopausal women, aged between 40 and 60 years and complaining of severe menopausal symptoms were recruited through newspaper advertisements.

METHODS

Women were randomly allocated to progestelle progesterone cream 60, 40, 20, 5 mg or placebo, to be applied daily for six months. Main outcome measures The primary efficacy variable was the psychological, somatic and vasomotor components of the Greene Climacteric Scale after six months. Secondary endpoints were incidence of hot flushes and night sweats, the nine subscales of the Medical Outcome Survey Short Form-36 (SF-36), serum progesterone, endometrial thickness and histology after six months. Adverse events were sought and recorded and followed up to resolution.

RESULTS

There were no statistically significant differences between any of the treatment groups and placebo for any of the components of the Greene Score. A statistically significant difference between the 20 mg group and placebo was found for the physical functioning (95% confidence interval [CI] 1.7-12.3; P=0.01) and social functioning (95% CI 1.9-16.7; P=0.01) scales of SF-36 after six months. No other statistically significant differences were found between any treatment group and placebo for any of the other secondary efficacy variables. There appeared to be a higher incidence of headache in the groups treated with progesterone cream.

CONCLUSIONS

Progesterone cream was no more effective than placebo for relief of menopausal symptoms.

Sex steroid induced negative mood may be explained by the paradoxical effect mediated by GABAA modulators

Certain women experience negative mood symptoms as a result of progesterone during the luteal phase of the menstrual cycle, progestagens in hormonal contraceptives, or the addition of progesterone or progestagens in sequential hormone therapy (HT). This phenomenon is believed to be mediated via the action of the progesterone metabolites on the GABA(A) system, which is the major inhibitory system in the mammalian CNS. The positive modulators of the GABA(A) receptor include allopregnanolone and pregnanolone, both neuroactive metabolites of progesterone, as well as benzodiazepines, barbiturates, and alcohol. Studies on the effect of GABA(A) receptor modulators have shown contradictory results; although human and animal studies have revealed beneficial properties such as anaesthesia, sedation, anticonvulsant effects, and anxiolytic effects, recent reports have also indicated adverse effects such as anxiety, irritability, and aggression. It has actually been suggested that several GABA(A) receptor modulators, including allopregnanolone, have biphasic effects, in that low concentrations increase an adverse, anxiogenic effect whereas higher concentrations decrease this effect and show beneficial, calming properties. The allopregnanolone increase during the luteal phase in fertile women, as well as during the addition of progesterone in HT, has been shown to induce adverse mood in women. The severity of these mood symptoms is related to the allopregnanolone serum concentrations in a manner similar to an inverted U-shaped curve. Negative mood symptoms occur when the serum concentration of allopregnanolone is similar to endogenous luteal phase levels, while low and high concentrations have less effect on mood. It has also been shown that progesterone/allopregnanolone treatment in women increases the activity in the amygdala (as measured with functional magnetic resonance imaging) in a similar way to the changes seen during anxiety reactions. However, it is evident that only certain women experience adverse mood during progesterone or GABA(A) receptor modulator treatments. Women with premenstrual dysphoric disorder (PMDD) have severe luteal phase related symptoms; in this phase, they show changes in GABA(A) receptor sensitivity and GABA concentrations that are related to the severity of the condition. These findings suggest that negative mood symptoms in women with PMDD are caused by the paradoxical effect of allopregnanolone mediated via the GABA(A) receptor.

CONCLUSION

Progesterone and progestagens induce negative mood, most probably via their GABA(A) receptor active metabolites. In postmenopausal women treated with progesterone and animals treated with allopregnanolone, there is a bimodal association between serum allopregnanolone concentration and adverse mood, resembling an inverted U-shaped curve. In humans, the maximal effective concentration of allopregnanolone for producing negative mood is within the range of physiological luteal phase serum concentrations.

Update on research and treatment of premenstrual dysphoric disorder

Many women in their reproductive years experience some mood, behavioral. or physical symptoms in the week prior to menses. Variability exists in the level of symptom burden in that some women experience mild symptoms, whereas a small minority experience severe and debilitating symptoms. For an estimated 5%-8% of premenopausal women, work or social functioning are affected by severe premenstrual syndrome. Many women in this group meet diagnostic criteria for premenstrual dysphoric disorder (PMDD). Among women who suffer from PMDD, mood and behavioral symptoms such as irritability, depressed mood, tension, and labile mood dominate. Somatic complaints, including breast tenderness and bloating, also can prove disruptive to women's overall functioning and quality of life. Recent evidence suggests that individual sensitivity to cyclical variations in levels of gonadal hormones may predispose certain women to experience these mood, behavioral, and somatic symptoms. Treatments include: antidepressants of the serotonin reuptake inhibitor class, taken intermittently or throughout the menstrual cycle; medications that suppress ovarian cyclicity; and newer oral contraceptives with novel progestins.

Estrogen and progestogen therapy in postmenopausal women

This Educational Bulletin discusses the effectiveness of hormone therapy (HT) for relieving vasomotor and urogenital symptoms and the side effects associated with such treatment; considers the evidence concerning the effects of HT on the risk of osteoporosis and related fractures and on the risks of coronary artery disease, dementia, and colorectal cancer; and considers the longer term effects of HT on the risks of stroke, venous thromboembolism, and cancer of the breast, endometrium, and ovary.

Premenstrual syndrome

Most women of reproductive age have some physical discomfort or dysphoria in the weeks before menstruation. Symptoms are often mild, but can be severe enough to substantially affect daily activities. About 5-8% of women thus suffer from severe premenstrual syndrome (PMS); most of these women also meet criteria for premenstrual dysphoric disorder (PMDD). Mood and behavioural symptoms, including irritability, tension, depressed mood, tearfulness, and mood swings, are the most distressing, but somatic complaints, such as breast tenderness and bloating, can also be problematic. We outline theories for the underlying causes of severe PMS, and describe two main methods of treating it: one targeting the hypothalamus-pituitary-ovary axis, and the other targeting brain serotonergic synapses. Fluctuations in gonadal hormone levels trigger the symptoms, and thus interventions that abolish ovarian cyclicity, including long-acting analogues of gonadotropin-releasing hormone (GnRH) or oestradiol (administered as patches or implants), effectively reduce the symptoms, as can some oral contraceptives. The effectiveness of serotonin reuptake inhibitors, taken throughout the cycle or during luteal phases only, is also well established.

Brain aging modulates the neuroprotective effects of estrogen on selective aspects of cognition in women: a critical review

Although there is now a substantial literature on the putative neuroprotective effects of estrogen on cognitive functioning in postmenopausal women, it is replete with inconsistencies. The critical period hypothesis, posited several years ago, attempts to account for the discrepancies in this literature by positing that estrogen treatment (ET) will protect aspects of cognition in older women only when treatment is initiated soon after the menopause. Indeed, evidence from basic neuroscience and from the animal and human literature reviewed herein provides compelling support for the critical period hypothesis. Although it is not known with certainty why estrogen does not protect cognition and may even cause harm when administered to women over the age of 65years, it is likely that the events that characterize brain aging, such as a reduction in brain volume and in neuronal size, alterations in neurotransmitter systems, and a decrease in dendritic spine numbers, form an unfavorable background that precludes a neuroprotective effects of exogenous estrogen on the brain. Other factors that have likely contributed to the discrepancies in the estrogen-cognition literature include differences in the estrogen compounds used, their route of administration, cyclic versus continuous regimens, and the concomitant use of progestins. This critical analysis attempts to define conditions under which ET may protect aspects of cognition in aging women while also considering the cost/benefit ratio for the treatment of women aged 50-59years. Suggestions for specific future research questions are also addressed.

Variations on hormone replacement therapy: an answer to the 'one dose fits all' Women's Health Initiative study

The Women's Health Initiative study worked on the assumption that one dose would fit all asymptomatic postmenopausal women. The investigators therefore often used the wrong dose, of the wrong hormones, on the wrong patients and therefore came to many wrong conclusions. Different combinations of different hormones are necessary for different symptoms and different age groups. Hormone replacement therapy may be commenced in the perimenopausal phase, the early postmenopause, the late postmenopause or after hysterectomy and bilateral salpingo-oophorectomy or a premature menopause. These all require different treatments. Similarly, various indications such as vasomotor symptoms, sexual problems, depression or the treatment/prevention of osteoporosis all need different combinations of estradiol and possibly progestogen and testosterone, according to the specific requirements of the patient.

Symptoms related to the menopause and sex steroid treatments

In the menopause transition, ovarian steroid production is gradually inhibited and around 35% of women will seek medical help for postmenopausal symptoms. The hot flush is a characteristic manifestation occurring in about 70% of women; it is associated with oestrogen withdrawal and disappears with oestrogen-based hormone replacement therapy. The exact mechanism behind it is still unclear but is probably related to heat loss mechanisms. The flush often occurs in parallel to changes in skin temperature, blood flow, pulse rate and pulses of luteinizing hormone (LH). These are probably secondary to a disturbance in the thermoregulatory centre of the CNS, which is anatomically close to neurons containing gonadotropin-releasing hormone. Depression is no more frequent in the menopausal transition than at other times in life. After surgical menopause, however, oestrogen improves low mood over placebo. In women with premenstrual syndrome, an increased feeling of well-being is associated with the pre-ovulatory oestrogen peak. Progestogens are associated with negative mood changes during the menstrual cycle, oral contraception and postmenopausal replacement therapy. Certain progesterone metabolites are anaesthetic and have anti-epileptic and anxiolytic properties, effects which are mediated via the type A gamma-aminobutyric acid (GABAA) receptor. Oestrogen is associated with increased sensory perception, locomotory activity, limb coordination and balance: this may help explain the increased frequency of bone fractures in the early postmenopausal period. Oestrogen improves memory and performance in patients with mild Alzheimer's dementia and increases epileptic activity in patients with partial epilepsy. These effects can be related to amplifying effects of oestrogen on excitatory amino acids in the CNS.

Ovarian steroids and premenstrual symptoms: a comparison of group differences and intra-individual patterns

To examine the relationship of gonadal hormone and symptom patterns across the menstrual cycle, women screened for 2-3 cycles completed an intensive study cycle; 26 had a low-severity symptoms (LS), 20, a premenstrual syndrome (PMS), and 26, a premenstrual magnification pattern (PMM). All completed daily symptom diaries and collected late afternoon urine samples which were assayed for pregnanediol and estradiol for that cycle. The PMS and PMM groups had significantly more positive cross-correlations of pregnanediol and symptoms than the LS group. Women in all groups had similar levels of estradiol and pregnanediol. Women with PMS and PMM patterns responded to progesterone differently than women with LS patterns: thus the former groups may not benefit from hormone therapies.

Pilot Study of the Efficacy and Safety of a Modified-Release Magnesium 250mg Tablet (Sincromag??) for the Treatment of Premenstrual Syndrome

BACKGROUND

Magnesium deficiency has been implicated as a possible contributing factor to some symptoms of premenstrual syndrome (PMS) and several studies have reported a lower intracellular magnesium concentration in women with PMS. Thus, it has been suggested that magnesium supplementation may improve certain symptoms in women with PMS.

OBJECTIVE

This open-label study assessed the efficacy and safety of a patented modified-release magnesium 250 mg tablet for improving symptoms in women affected by PMS.

METHODS

After a 3-month observational period, women aged 18-45 years with a regular menstrual cycle (from 25-35 days) who were affected by PMS (determined by a score of > or =25 points on a PMS questionnaire) [n = 41] were given the modified-release magnesium tablet over three menstrual cycles, beginning 20 days after the start of their last menstrual period and continuing until the start of their next menstrual period.

RESULTS

PMS symptoms improved during magnesium treatment. After 3 months, the mean total PMS score (primary endpoint), as assessed by the investigator using Moos' Modified Menstrual Distress Questionnaire, was significantly lower than before therapy (p < 0.0001). During the same period, the mean PMS scores, as recorded in patients' diaries (secondary efficacy variables), also showed significant improvements (p < 0.0001 for all subscales). The relative decreases in total PMS scores, as assessed by investigator and patient, were 35.1% and 33.5%, respectively. The magnesium tablet was well tolerated, with vertigo the only treatment-related adverse event reported (one patient).

CONCLUSIONS

We concluded that modified-release magnesium was effective in reducing premenstrual symptoms in women with PMS in this preliminary study.

Progesterone and progestins: effects on brain, allopregnanolone and beta-endorphin

The increased use of hormonal therapies over the last years has led to improve the knowledge of pharmacological, biochemical and metabolic properties of several progestins and their effects in target tissues, such as the central nervous system. Progesterone and synthetic progestational agents are able to modulate the synthesis and release of several neurotransmitters and neuropeptides in response to specific physiological and pathological stimuli. While these actions may relay on differential activation of progesterone receptor or recruitment of intracellular pathways, some of the differences found between synthetic progestins may depend on the specific conversion to neuroactive steroids, such as the 3-alpha, 5-alpha reduced metabolite, allopregnanolone. This is a potent endogenous steroid that rapidly affects the excitability of neurons and glia cells through direct modulation of the GABA-A receptors activity exerting hypnotic/sedative, anxiolytic, anaesthetic and anticonvulsive properties. Estrogens increase the CNS and serum levels of allopregnanolone and the addition of certain but not all synthetic progestins determines a further increase in allopregnanolone levels, suggesting that the metabolism into this reduced product is related to the chemical structure of progestin molecule used. In addition, depending on specific progestin molecule used, different interaction are found with the estradiol-induced beta-endorphin synthesis and release, showing that diverse progestins have specific and divergent actions on the opiatergic system. These results highlight the concept that natural and synthetic progesterone receptor agonists may systematically induce different biological actions in CNS. This may have far-reaching implications for the clinical effects and related indications of each compound.

Are there differential symptom profiles that improve in response to different pharmacological treatments of premenstrual syndrome/premenstrual dysphoric disorder?

Current evidence suggests that the accepted treatments for premenstrual syndrome (PMS)/premenstrual dysphoric disorder (PMDD) have similar overall efficacy. While these treatments are more effective than placebo, response rates associated with them are far from satisfactory (<60%), such that, irrespective of treatment modality, there remain a significant number of women who are unresponsive to current conventional pharmacological therapy. The available data on response rates of specific types of premenstrual symptoms to, or symptom profiles that are most amenable to, each treatment modality are limited and not well defined because most studies were not designed to assess specific symptom profiles. Those studies that have attempted to evaluate which symptom profiles respond to specific therapies have revealed variations within the individual modalities, as well as between the different modalities. It appears that suppression of ovulation ameliorates a broad range of behavioural as well as physical premenstrual symptoms. SSRIs are most effective for irritability and anxiety symptoms, with lesser efficacy for 'atypical' premenstrual symptoms. GABAergic compounds are most efficacious for anxiety and anxious/depressive symptoms, while dopamine agonists, particularly bromocriptine, are perhaps most efficacious for mastalgia. Overall treatment response rates may improve if treatments are targeted at well-defined subgroups of patients. Re-analysis of available datasets from randomised clinical trials may shed more light on the notion that targeting women with specific premenstrual symptom profiles for specific treatment modalities would improve response rates beyond the current ceiling of approximately 60%. Such information would also improve understanding of the putative pathophysiological mechanisms underlying PMS and PMDD, and may point to a more specific diagnosis of these conditions.

Allopregnanolone concentration and mood--a bimodal association in postmenopausal women treated with oral progesterone

RATIONALE

Allopregnanolone effects on mood in postmenopausal women are unclear thus far.

OBJECTIVES

Allopregnanolone is a neuroactive steroid with contradictory effects. Anaesthetic, sedative, and anxiolytic as well as aggressive and anxiogenic properties have been reported. The aim of this study is to compare severity of negative mood between women receiving different serum allopregnanolone concentrations during progesterone treatment.

MATERIALS AND METHODS

A randomized, placebo-controlled, double-blind, crossover study of postmenopausal women (n=43) treated with 2 mg estradiol daily during four treatment cycles. Oral micronized progesterone at 30, 60, and 200 mg/day, and placebo were added sequentially to each cycle. Participants kept daily symptom ratings using a validated rating scale. Blood samples for progesterone and allopregnanolone analyses were collected during each treatment cycle.

RESULTS

During progesterone treatment, women had significantly higher negative mood scores when allopregnanolone serum concentration was in the range of 1.5-2 nmol/l compared to lower and higher concentrations. In addition, women displayed a significant increase in negative mood during the progesterone treatment period, compared to the estradiol-only period when 30 mg progesterone daily was used. On the other hand, treatment with higher doses of progesterone had no influence on negative mood.

CONCLUSIONS

Mood effects during progesterone treatment seem to be related to allopregnanolone concentration, and a bimodal association between allopregnanolone and adverse mood is evident.

Ovariotomy for menstrual madness and premenstrual syndrome--19th century history and lessons for current practice

Ovariotomy--the removal of normal ovaries, known as Battey's Operation--began in 1872 and became the fashionable treatment of menstrual madness, neurasthenia, nymphomania, masturbation and "all cases of insanity". This practice was supported by distinguished gynecologists and psychiatrists, becoming one of the great medical scandals of the 19th century. In modern times, if menstrual madness is considered to be premenstrual dysphoric disorder (PMDD), and ovariotomy, the surgical equivalent of ovulation suppression of GnRH analogues, it can be argued that the surgery would have been effective for this limited indication, although the side effects of long-term estrogen deficiency would have made the treatment unacceptable. Currently, the successful hormonal treatment of PMDD is one of suppression of ovulation and removal of the cyclical hormonal changes in the luteal phase, probably progesterone, which is the essential cause of PMDD. Such therapy would be by GnRH analogues, transdermal estradiol and, in a few cases, the surgical option of hysterectomy and bilateral salpingo-oophorectomy with adequate hormone replacement. A study of medical history can help us prevent the mistakes of over-enthusiasm but positive lessons can be learned.

Action by and sensitivity to neuroactive steroids in menstrual cycle related CNS disorders

Neuroactive steroids are a large group of substances having effect in the brain and on brain function. The steroids most studied are allopregnanolone (ALLO), tetrahydrodesoxycorticosterone (THDOC), pregnenolone sulfate (PS) dihydroepiandrosteronesulfate (DHEAS), and estradiol (E2). ALLO and THDOC are called gamma-aminobutyric acid (GABA) steroids as they are positive modulators of the GABAA receptor in a similar way as benzodiazepines, barbiturates, and alcohol. GABA steroids not only have similar behavioral effects as benzodiazepines and barbiturates but, possibly, also similar adverse effects as well. This review aims to elucidate the possible role that neuroactive steroids play in the development of mood disorders in women. One of the most clear-cut examples of the interaction between mood, neuroactive steroids, and the GABA system is premenstrual dysphoric disorder (PMDD), which is a cluster of negative mood symptoms occurring during the luteal phase of the menstrual cycle in 2-6% of reproductive women. Furthermore, certain women also experience adverse mood effects during sequential progestin addition to postmenopausal estrogen treatment, which is why the role of neuroactive steroids in postmenopausal women is also addressed in this review.

Progesterone and medroxyprogesterone acetate effects on central and peripheral allopregnanolone and beta-endorphin levels

The increased use of hormonal therapies has led to the study of the properties of different progestin molecules and their effects on the central nervous system. The central and peripheral levels of neurosteroid allopregnanolone and the opioid peptide beta-endorphin (beta-END) are regulated by estrogens. The aim of the present study was to investigate the effects of a 2-week oral treatment with micronized progesterone or medroxyprogesterone acetate (MPA) alone or in addition to estradiol valerate (E2V) on central and peripheral allopregnanolone and beta-END levels in ovariectomized (OVX) female rats. Thirteen groups of Wistar OVX rats received one of the following treatments: oral progesterone (2, 4 or 8 mg/kg/day); oral MPA (0.05, 0.1 or 0.2 mg/kg/day); E2V (0.05 mg/kg/day); E2V + progesterone (0.05 mg/kg/day + 2, 4 or 8 mg/kg/day), or E2V + MPA (0.05 mg/kg/day + 0.05, 0.1 or 0.2 mg/kg/day) for 14 days. One group of fertile and one group of OVX rats were used as controls. The concentration of allopregnanolone was assessed in the frontal and parietal lobes, hypothalamus, hippocampus, anterior pituitary, adrenals and serum, while the beta-END content was assessed in the frontal and parietal lobes, hypothalamus, hippocampus, anterior and neurointermediate pituitary, and plasma. E2V administration reverted the ovariectomy-induced reduction in allopregnanolone and beta-END. Progesterone and MPA increased allopregnanolone levels in all tissues except in the adrenal gland. The combined administration of progesterone or MPA and E2V determined a further increase in allopregnanolone levels with respect to E2V alone except in the adrenal gland and hippocampus only after MPA treatment. Progesterone did not affect beta-END levels in the frontal and parietal lobes, hippocampus and anterior pituitary, while it caused an increase plasma, hypothalamic and neurointermediate pituitary beta-END levels. MPA only affected beta-END levels in the hippocampus and in the neurointermediate lobe. The combined administration of progesterone or MPA and E2V did not alter the effect of estradiol or it determined a further dose-dependent increase in beta-END levels. In conclusion, this study demonstrates that progesterone and MPA have a similar but not identical effect on central and peripheral allopregnanolone and beta-END levels. Their association with an estrogenic compound does not interfere with the positive effects produced by estrogen on allopregnanolone and beta-END brain content.

Neuroactive steroid effects on cognitive functions with a focus on the serotonin and GABA systems

This article will review neuroactive steroid effects on serotonin and GABA systems, along with the subsequent effects on cognitive functions. Neurosteroids (such as estrogen, progesterone, and allopregnanolone) are synthesized in the central and peripheral nervous system, in addition to other tissues. They are involved in the regulation of mood and memory, in premenstrual syndrome, and mood changes related to hormone replacement therapy, as well as postnatal and major depression, anxiety disorders, and Alzheimer's disease. Estrogen and progesterone have their respective hormone receptors, whereas allopregnanolone acts via the GABA(A) receptor. The action of estrogen and progesterone can be direct genomic, indirect genomic, or non-genomic, also influencing several neurotransmitter systems, such as the serotonin and GABA systems. Estrogen alone, or in combination with antidepressant drugs affecting the serotonin system, has been related to improved mood and well being. In contrast, progesterone can have negative effects on mood and memory. Estrogen alone, or in combination with progesterone, affects the brain serotonin system differently in different parts of the brain, which can at least partly explain the opposite effects on mood of those hormones. Many of the progesterone effects in the brain are mediated by its metabolite allopregnanolone. Allopregnanolone, by changing GABA(A) receptor expression or sensitivity, is involved in premenstrual mood changes; and it also induces cognitive deficits, such as spatial-learning impairment. We have shown that the 3beta-hydroxypregnane steroid UC1011 can inhibit allopregnanolone-induced learning impairment and chloride uptake potentiation in vitro and in vivo. It would be important to find a substance that antagonizes allopregnanolone-induced adverse effects.

Bleeding profiles and effects on the endometrium for women using a novel combination of transdermal oestradiol and natural progesterone cream as part of a continuous combined hormone replacement regime

OBJECTIVE

Many women are seeking alternatives to conventional forms of hormone replacement. This study evaluates the endometrial effects of natural progesterone cream used in conjunction with transdermal oestradiol.

DESIGN

Open plan study conducted over 48 weeks.

SETTING

Tertiary referral London teaching hospital.

POPULATION

Women at least two years postmenopausal.

METHODS

Women were recruited nationally. They applied 40 mg transdermal natural progesterone cream and 1 mg transdermal oestradiol daily.

MAIN OUTCOME MEASURES

Endometrial histology, assessed by pipelle endometrial biopsy, ultrasound assessment of endometrial thickness and bleeding diaries.

RESULTS

Fifty-four women were recruited of which 41 completed the study. Mean age was 57.4 years. Thirty-two percent of women had evidence of inadequate endometrial opposition (proliferative or hyperplastic) at the end of 48 weeks. At baseline, women had a mean endometrial thickness of 3.3 mm, which had significantly thickened to a mean of 5.3 mm by 24 weeks (P < 0.001). By 48 weeks, there was significantly greater increase in endometrial thickness from baseline in those women who displayed inadequate endometrial opposition, compared with those women who had adequate endometrial opposition (P= 0.004). At 24 weeks, 48% of women had remained entirely amenorrhoeic. By the end of the study, 35% of women had been entirely amenorrhoeic and 50% had had either no bleeding or spotting alone. The number of bleeding episodes did not reduce with time.

CONCLUSIONS

The dose of natural progesterone cream in this study was insufficient to fully attenuate the mitogenic effect of oestrogen on the endometrium. We would not recommend this combination of hormones to be used by postmenopausal women.

Estrogen-related mood disorders: reproductive life cycle factors

Women are at higher risk throughout their reproductive lives than are men for major depression. Numerous molecular and clinical studies have implicated estrogen in modulating brain function including that related to mood. In an attempt to present a conceptual model, the literature of the past 30 years on mood and well-being throughout reproductive life is reviewed as it relates to activity of endogenous, bio-identical, and synthetic estrogen in women. Results indicate that sudden estrogen withdrawal, fluctuating estrogen, and sustained estrogen deficit are correlated with significant mood disturbance. Clinical recovery from depression postpartum, perimenopause, and postmenopause through restoration of stable/optimal levels of estrogen has been noted.

Relationship between allopregnanolone and negative mood in postmenopausal women taking sequential hormone replacement therapy with vaginal progesterone

OBJECTIVE

To compare severity of negative mood and physical symptoms between women with different progesterone, allopregnanolone, and pregnanolone plasma concentrations during sequential Hormone Replacement Therapy (HRT) with vaginal progesterone suppositories.

DESIGN

A randomized, placebo-controlled, double-blind, crossover study.

METHOD

Postmenopausal women (n=36) with climacteric symptoms were treated with 2mg estradiol daily during three 28-day cycles. Vaginal progesterone suppositories with 400, 800 mg/day or placebo were added sequentially for 14 days per cycle. Daily symptom ratings using a validated rating scale were kept. Blood samples for progesterone, allopregnanolone, and pregnanolone radioimmunoassays were collected during each treatment cycle.

RESULTS

Women were divided into three groups (low, medium, and high) based on plasma allopregnanolone concentration during progesterone treatment. The concentration of allopregnanolone in the medium group corresponds to the concentration seen during the mid luteal phase of the menstrual cycle. Within women with medium allopregnanolone concentration significantly more negative mood and physical symptoms were rated during progesterone treatment compared to treatment with unopposed estrogen or placebo. Between women significantly more negative mood symptoms were seen during progesterone treatment cycles with medium allopregnanolone concentration compared to cycles with low concentration. Plasma progesterone, allopregnanolone, and pregnanolone concentrations increased with increasing progesterone dose. Progesterone and allopregnanolone plasma concentrations increased 2h after vaginal administration of progesterone at 400 and 800 mg/day.

CONCLUSION

Vaginal progesterone in sequential HRT causes negative mood, most likely mediated via allopregnanolone.

A comparison of the central effects of different progestins used in hormone replacement therapy

OBJECTIVE

To evaluate the central effect exerted by different progestins used for hormone replacement therapy.

METHODS

Randomised, placebo-controlled study. One hundred-twenty postmenopausal women on continuous hormonal replacement therapy with transdermal estradiol (50 microg per day) associated, for 10 days every 28 days, with four different progestins: dydrogesterone (DYD; 10 mg per day; n = 20), medroxyprogesterone acetete (MPA; 10 mg per day; n = 20), nomegestrol acetate (NMG; 5 mg per day; n = 20) or norethisterone acetate (NETA; 10 mg per day; n = 20). Other 40 women, 10 for each treatment group, were used as controls and were monitored for a single cycle of 28 days during the administration of transdermal estradiol plus placebo. Morning basal body temperature (BBT) was monitored for 28 days. Anxiety, by the state-trait anxiety inventory, and depression, by the self-evaluation depression scale of Zung, were evaluated just prior to and in the last 2 days of the 10-day progestins adjunct.

RESULTS

All progestins except DYD increased (P < 0.0001) BBT by 0.3-0.5 degrees C. Anxiety was decreased by DYD (- 2.3 + 1.1; P < 0.01) and MPA (- 1.5 + 0.5; P < 0.01), but not by NMG or NETA. Depression did not significantly increase during progestins and actually decreased during MPA (- 3.0 + 0.7; P < 0.01). Only the effect of DYD on anxiety and that of MPA on depression were significant versus the control group (P < 0.05 ).

CONCLUSIONS

Different progestins exert different central effects. DYD has the peculiarity of not increasing BBT and of decreasing anxiety, which is also decreased by MPA. Depression is not negatively affected by the tested progestins and it may be ameliorated by MPA. The present data may help to individualise the progestin choice of hormone replacement therapy.

The case for less-than-monthly progestogen in women on HT: is transvaginal ultrasound the key?

Unopposed estrogen (previously called ERT, now referred to as ET) increases a patient's risk of endometrial cancer. The addition of a progestogen to estrogen (previously called HRT, now referred to as HT) will decrease that additional risk of endometrial cancer although it will not eliminate it. Initially this was always done in a sequential fashion. More recently, continuous-combined HT, utilizing daily progestogen, has been popularized. Increasingly, published data points to progestogen and estrogen together causing an increase in the risk of breast cancer two to three times above that of estrogen alone. In the past, less-than-monthly progestogen has been attempted. It results in less bleeding, as well as some simple hyperplasia. Transvaginal ultrasound has a very poor positive predictive value (4% for serious endometrial disease and 9% for any endometrial disease) but a very high negative predictive value (99%) when the echo is distinct, and thin (<5 mm). Thus, patients with an initial thin distinct endometrial echo can begin with unopposed estrogen. At 3 months, they get a progestogen withdrawal of 12 days and the endometrial echo is measured again. If thin and distinct (<5 mm), the interval between progestogen withdrawals can be further increased and in some women potentially eliminated. If the echo is not sufficiently thin, although this does not necessarily indicate anything more than proliferative endometrium, those patients may require either monthly progestogen or continuous-combined HT. The advantage for the successful patient is less progestogen exposure, as little as 24 days per year in most patients, and less bleeding (although because the majority will bleed, the patient has to be willing to accept a withdrawal bleed that she has planned and can control the timing of by when she chooses to take the progestogen). The patient should have an easily visible thin endometrial echo before initiation. Some women will not lend themselves to a reliable assessment of the endometrial echo (at least not without saline infusion enhancement). Examples of such patients are those with an axial uterus, coexisting fibroids, marked obesity, and previous endometrial ablation. Such an approach will allow a large number of patients whose initial endometrial echo is easily visualized to minimize their progestogen dose.