Monitoring of oestrogen replacement therapy by vaginosonography of the endometrium

Breast cancer risk in the WHI study: The problem of obesity

In the climacteric, about 40% of the women have occult breast tumors the growth of which may be stimulated by hormones. Many genetic, reproductive and lifestyle factors may influence the incidence of breast cancer. Epidemiological data suggest that the increase in the relative risk (RR) of breast cancer induced by hormone replacement therapy (HRT) is comparable with that associated with early menarche, late menopause, late first birth, alcohol consumption, etc. One of the most important risk factors is obesity which exceeds the effect of HRT by far, and in overweight postmenopausal women the elevated risk of breast cancer is not further increased by HRT. As in the WHI study the majority of women was overweight or obese, this trial was unsuitable for the investigation of breast cancer risk. In the women treated with an estrogen/progestin combination, the RR of breast cancer rose only in those women who have been treated with hormones prior to the study, suggesting a selection bias. In the women not pretreated with hormones, it was not elevated. In the estrogen-only arm of the WHI study, there was no increase but a steady decrease in the RR of breast cancer during 6.8 years of estrogen therapy. This result was unexpected, as estrogens are known to facilitate the development and growth of breast tumors, and the effect is enhanced by the addition of progestins. Obese women are at high risk to develop a metabolic syndrome including insulin resistance and hyperinsulinemia. In postmenopausal women, elevated insulin levels are not only associated with an increased risk for cardiovascular disease, but also for breast cancer. This might explain the effects observed in both arms of the WHI study: HRT with relative low doses of estrogens may improve insulin resistance and, hence, reduce the elevated breast cancer risk in obese patients, whereas this beneficial estrogen effect may be antagonized by progestins. The principal options for the reduction of breast cancer risk in postmenopausal women are the prevention of overweight and obesity to avoid the development of hyperinsulinemia, the medical treatment of insulin resistance, the use of low doses of estrogens and the reduction of exposure to progestins. The latter might include long-cycles with the sequential use of appropriate progestins every 3 months for 14 days. There are large inter-individual variations in the proliferative response to estrogens of the endometrium. Control by vaginalsonography and progestin challenge tests may help to identify those women who may be candidates for low-dose estrogen-only therapy.

Endometrial safety of hormone replacement therapy: review of literature

Unopposed estrogens for treating menopausal symptoms were extensively used when epidemiological findings associated them with an increased endometrial cancer risk. Adding progestogens reverse this side effect efficiently but patient, dose, type and especially time during which the progestogen is administered are important. Long-term uterine safety of the long cycle HRT with administration of the progestogen every 3 months remains unclear. Because regular bleeding lowers compliance, continuous combined estrogen-progestogen treatment has become popular. Many different regimens are now available using oral, transdermal, subcutaneous, intravaginal or intra-uterine application of the estrogen and/or progestogen. Available but inadequate studies seem to point towards a slightly decreased endometrial cancer risk with continuous combined preparations compared with non-HRT-users and an increased risk with long-term oral but not vaginal treatment with low-potency estrogen formulations such as estriol. Newer compounds for menopausal health such as tibolone and raloxifene seem to be safe. As for any women with abnormal vaginal bleeding, those on HRT must have an intra-uterine evaluation. Transvaginal ultrasound (TVU) is very accurate in predicting a normal uterine cavity but inaccurate in predicting endometrial pathology because of a low specificity and positive predictive value of a thick echogenic endometrium. In all such cases a three-dimensional visualisation of intra-uterine lesions is more accurate. Periodic examination with TVU and/or endometrial biopsy of HRT exposed endometrium in asymptomatic women is not cost-effective. The available limited data on the use of HRT in hysterectomised women for early stage endometrial cancer show little evidence in terms of recurrence.

Ultrasonographic endometrial monitoring during continuous-sequential hormonal replacement therapy regimen in postmenopausal women

OBJECTIVE

To evaluate the endometrial thickness in different periods of a continuous-sequential HRT regimen and to correlate the ultrasonographic findings with the histological patterns.

METHODS

The study was structured in two phases. In the 1st phase, 37 postmenopausal women (group A) treated by at least 6 months with a conventional continuous-sequential hormonal replacement therapy (cs-HRT) regimen were enrolled. In all patients, the endometrial thickness was measured at the 7th, 14th, 21st and 25th day of the cycle using transvaginal ultrasonography (TV-USG). In the 2nd phase of the study, other 41 postmenopausal women (group B) were enrolled and treated with the same sc-HRT regimen. At entry and after six cycles of cs-HRT, an endometrial biopsy was performed. The endometrial pattern was related with endometrial thickness. Either the evaluations were performed immediately after progestogen withdrawal bleeding, as showed by 1st phase results.

RESULTS

The results of the 1st phase of the study showed a mean endometrial thickness significantly lower at 7th day of the cycle compared to 14th, 21st and 25th day (4.3+/-1.2 versus 6.6+/-2.9, 7.8+/-4.2 and 7.4+/-4.6 mm+/-SD, respectively). After six cycles of cs-HRT (2nd phase of the study), the mean endometrial thickness was significantly increased in comparison with basal values (4.2+/-1.5 versus 2.8+/-1.2 mm+/-SD; P<0.05). Endometrial biopsies showed 13 cases (39.4%) of atrophy and 20 cases (60.6%) of proliferative endometrium. Mean endometrial thickness in case of atrophy was lower than in presence of a proliferative endometrium (3.7+/-1.2 versus 4.4+/-1.4 mm+/-SD; not significant). Endometrial thickness was <4 mm in 16 cases (11 of atrophic and five of proliferative endometrium), between 4 and 5 mm in 15 cases (13 of proliferative and two of atrophic endometrium) and between 5 and 6 mm in two cases (either case of proliferative endometrium).

CONCLUSIONS

The best timing for monitoring endometrial thickness during cs-HRT regimens is the period immediately after withdrawal bleeding improving the reliability of the ultrasonographic exam to identify endometrial pathologies.

Ultrasonographic and morphological studies of the postmenopausal endometrium using unopposed estrogen replacement therapy with regular pause: a prospective preliminary study

Hormone replacement therapy with progestogen is known to have severe side effects or complications in certain patients.

OBJECTIVE

The goal of this study is to evaluate the safety and efficacy of an alternative treatment regimen with a mensal pause using both transvaginal sonography (TVS) and endometrial biopsy to follow patients.

METHODS

A total of 30 postmenopausal women were treated with unopposed estrogen for 21 days each month followed by a regular pause of 9-10 days, and were studied prospectively for 18 months. The TVS measurements of endometrial thickness and biopsy of the endometrium were done on the 21st day of treatment and the 7th day of the pause at 6-month intervals throughout the study.

RESULTS

There was a significant decrease of proliferative activity at all three time points during the study (6, 12 and 18 months) when tested on the 7th pause day (PD7). The percentage of patients with hyperplasia without nuclear atypia and endometrial thickness > or =8mm was 32% at 6 months, but decreased to 22 and 19% at 12 and 18 months, respectively. All cases of hyperplasia regressed after the hormonal pause throughout the treatment period.

CONCLUSIONS

This study presents an alternative treatment regimen for select patients having side effects or complications from progestogen administration; however, studies evaluating the safety and efficacy of this regimen over longer time periods are necessary.

Prescribing hormone replacement therapy for menopausal symptoms

This paper addresses the clinical presentation of menopause, pretreatment assessment for hormone replacement therapy, benefits and risks of this treatment, common hormone replacement regimens and their side effects, and patient management. The case-based discussion focuses on the clinical management of a patient who is considering hormone replacement therapy for menopausal symptoms.

Adverse endometrial effects during long cycle hormone replacement therapy. Scandinavian Long Cycle Study Group

OBJECTIVES

Treatment with unopposed estrogen is known to increase the risk of endometrial hyperplasia, atypia, and carcinoma, and therefore the administration of a progestin during hormone replacement therapy (HRT) is recommended. The addition of a progestin may cause unwanted side effects. Progestin administration of various durations are therefore used in HRT.

STUDY DESIGN

Data were obtained about endometrial histopathology, bleeding interval and compliance in 240 early postmenopausal women receiving HRT with a progestin administered for 10 days during 12 week or 4 week cycles of estrogen administration. These regimens were studied for as long as 4 years. The daily estrogen given was 17beta-estradiol 2 mg per day which was reduced to 1 mg day during the last 6 days of each cycle. The progestin used was norethindrone acetate, given at a dose of 1 mg per day.

RESULTS

The incidence of endometrial hyperplastic changes, i.e. simple or complex hyperplasia, atypia or cancer, was significantly higher in the 12 weeks cycle than in the monthly cycle group (P = 0.003), with an overall annual incidence of 5.6% in the 12 weeks cycle group and 1% in the monthly cycle group. One case of atypical hyperplasia and one case of endometrial adenocarcinoma was observed in the long cycle group. Long cycle treatment produced more irregular bleeding pattern. Accordingly, the rate of drop-out due to bleeding was significantly higher in the long cycle group (P<0.01).

CONCLUSION

We conclude that the long cycle HRT modality investigated did not improve compliance and may increase the risk of endometrial hyperplasia and eventually cancer compared to conventional HRT with a monthly cycle. Caution using long cycle HRT regimens is advisable, and careful monitoring of the endometrium during treatment is recommended.

Comparison of transvaginal ultrasonography and endometrial biopsy in endometrial surveillance in postmenopausal HRT users

OBJECTIVES

To compare transvaginal ultrasonography with histological findings in endometrial evaluation of postmenopausal women using hormone replacement therapy and to evaluate endometrial safety of three hormone replacement therapy regimens.

METHODS

In a randomized, comparative study in postmenopausal women, endometrial safety was evaluated using (1) no hormone replacement therapy, (2) oral micronized 17 beta-estradiol/oral sequential dydrogesterone, (3) transdermal 17 beta-estradiol/oral sequential dydrogesterone, or (4) oral tibolone. 85 Non-hysterectomised subjects underwent transvaginal ultrasonography immediately before Pipelle biopsy at baseline and subsequently after 12 and 24 months. Endometrial thickness and uterine dimensions were determined by transvaginal ultrasonography, and endometrial thickness (double-layer) was compared with biopsy results.

RESULTS

Endometrial evaluation was conveniently performed by transvaginal ultrasonography, and endometrial thickness correlated well with biopsy findings. If endometrial thickness was < 5 mm, the endometrial biopsy sample was either inactive/atrophic or insufficient for histopathological diagnosis. Hyperplastic or malignant changes were not reported. After 24 months, endometrial thickness was increased both in the oral (P < 0.001) and transdermal (P < 0.001) 17 beta-estradiol/dydrogesterone groups, whereas with tibolone the change in endometrial thickness was not different from controls.

CONCLUSION

transvaginal ultrasonography of the endometrium reliably predicts the histological picture in hormone replacement therapy users. Using 5 mm endometrial thickness as cut-off point, more than 75% of biopsies could be avoided. All three hormone replacement therapies were safe with respect to the endometrium. With sequential 17 beta-estradiol/dydrogesterone the expected progestogen-induced secretory pattern was observed, whereas endometrial histology under tibolone closely mimicked the natural atrophic postmenopausal state.

Endometrial sonographic and histologic findings in women with and without hormonal replacement therapy suffering from postmenopausal bleeding

OBJECTIVES

To evaluate, in women with postmenopausal bleeding, the effect of hormonal replacement (HRT) therapy on the endometrial thickness as measured by transvaginal sonography in relation to endometrial histology.

METHODS

1110 women with sequential/progestin treatment (E + P) (n = 202), with Estriol treatment (n = 149) or without HRT (n = 759) and postmenopausal bleeding were examined by transvaginal sonography (TVS) prior to curettage, with special reference to the relation of endometrial thickness to its histopathology.

RESULTS

The distribution of endometrial pathology was different in those women with E + P and Estriol compared with those without HRT. Endometrial pathology was found most frequently in women with an endometrium exceeding 8 mm in thickness. Furthermore, the incidence was found to increase with increasing endometrial thickness in all treatment groups. Atrophy was found significantly more often in women without HRT. Hormonal effects on the endometrium were found significantly more often in women with E + P and Estriol. Endometrial hyperplasia was found most commonly in women with Estriol in the thickness group 5 8 mm (P < 0.001) as compared to those with HRT and without HRT. Endometrial cancer occurs most in women without HRT, in those women with an endometrium exceeding 8 mm in thickness as compared both to the E + P (P < 0.001) group and to the Estriol (P < 0.001) group. Endometrial cancer did not occur in any woman (with E + P, Estriol or without HRT) with an endometrial thickness of < or = 4 mm.

CONCLUSIONS

TVS is of value for excluding endometrial pathology in women with HRT and postmenopausal bleeding. The distribution of endometrial findings and histopathological diagnosis in women with abnormal postmenopausal bleeding was different in women with E + P than in women without HRT. Furthermore, the cut-off for excluding endometrial abnormalities is the same in both groups i.e. < or = 4 mm.

Management of the menopause and HRT by ultrasound

Recent improvement of the transvaginal grey-scale and colour Doppler ultrasound scanning permits to investigate the morphology and the perfusion parameters of the female pelvic organs in the menopause. Data from detailed scanning of the ovaries and the uterus reflect the hormonal status, but the menopausal age from the last menstrual bleeding (LMB) and the sequence of the HRT given must be taken into consideration. Screening for endometrial pathology is advisable in the days after the withdrawal bleeding in women taking HRT. The positive vascular changes and increased peripheral perfusion in women with HRT detected by Doppler ultrasound are due to the oestrogen's vasodilator effect, which leads to cardiovascular and cerebrovascular protection. Changes of the uterine perfusion during the combined sequential HRT cycle doesn't seem to reflect the reverse effect of the progestin to oestrogen on the general vasculature, but correlates to the vascular changes of the normal menstrual cycle. The disappearing uterine notch in the menopause suggests decreasing vessel compliance. In women taking HRT the uterine notch persists or even may reappear years after the LMB, as a sign of the vessel compliance reserve probably activated by oestrogen and may act also as an indicator of the effect of HRT on arterial status.

Ultrasound in gynecology: endometrium

With the development and clinical application of transvaginal transducers/probes (TVS) the sonographic imaging of the endometrium was greatly enhanced compared with abdominal ultrasound. Also, the discomfort of a full bladder associated with abdominal ultrasound could be avoided. A shorter distance between probe and target allowed the use of higher frequency transducers, thereby achieving improved imaging. This review will only discuss the use of TVS, but it does not mean that abdominal ultrasound should not or cannot be used when dealing with the postmenopausal uterus. Transvaginal sonography (TVS) provides a valuable tool for the diagnosis of a wide range of gynecological disorders including those of the uterus and endometrium. The ability of TVS to depict the thickness and morphology of the endometrium has been established in both office and hospital settings. This article will discuss and illustrate the clinical and research applications of transvaginal sonography in relation to the endometrium in both symptomatic and asymptomatic postmenopausal women. The article is of particular relevance today given the number of women who are undergoing transvaginal ultrasonography in the absence of symptoms as a part of their routine check ups. There is a paucity of data relating to the management of apparent ultrasound abnormalities in such women. In symptomatic women or for women at risk of developing endometrial pathology, a technique that could reduce the number of biopsy procedures would be of value. Hysteroscopy, dilatation and curettage (D & C) as well as other endometrial sampling methods are all invasive, thus it would be of benefit if a way could be found to assess the endometrium using a relatively non-invasive approach. Such a technique would need to be relatively easy to learn and perform, as well as being well accepted by the patients. We believe that transvaginal sonography fulfills many of these requirements, the following review will attempt to put forward some of the evidence to support this view.

Comparison of endometrial growth produced by unopposed conjugated estrogens or by micronized estradiol in postmenopausal women

OBJECTIVE

When unopposed estrogen replacement treatment is used, what is the pattern of endometrial growth? Does endometrial growth differ for various dosages and formulations?

STUDY DESIGN

A total of 87 postmenopausal women, median age 57 years (mean 56.7 +/- 5.6 years, range 45 to 69 years), were studied in a prospective, randomized, open clinical trial lasting 24 weeks. The treatment arms consisted of micronized estradiol, 0.5 or 1.0 mg (Estrace, Bristol-Myers Squibb, Princeton, N.J.), and conjugated estrogens, 0.625 mg (Premarin, Wyeth-Ayerst, Philadelphia). Endometrial thickness was evaluated by vaginal probe ultrasonography at outset and after 6, 12, and 24 weeks of treatment.

RESULTS

Endometrial growth was progressive over time; more than half the total 24-week growth occurred in the first 6 weeks. The mean weekly rate (+/-SD) of endometrial growth was similar for micronized estradiol, 1.0 mg, and conjugated estrogens, 0.625 mg (0.19 +/- 0.15 mm for micronized estradiol, 1.0 mg, and 0.19 +/- 0.14 mm for conjugated estrogens, 0.625 mg). These rates differed to a statistically significant degree (p < 0.05) from the growth rate produced by micronized estradiol, 0.5 mg (0.08 +/- 0.16 mm). Both unscheduled and scheduled uterine bleeding was less likely among women using micronized estradiol, 0.5 mg, than among women using micronized estradiol, 1.0 mg, or conjugated estrogens, 0.625 mg.

CONCLUSIONS

In a 24-week trial the therapeutically equivalent estrogen doses produced the same mean increment in endometrial thickness, but half-strength estradiol produced half as much endometrial growth.

Hysteroscopy and transvaginal sonography in menopausal women receiving hormone replacement therapy

STUDY OBJECTIVE

To evaluate the endometrial cavity of menopausal women with irregular bleeding while receiving hormone replacement therapy.

DESIGN

Comparative evaluation of hysteroscopic and biopsy findings.

SETTING

A center for reproductive studies.

PATIENTS

Forty-one patients receiving different regimens of hormone replacement therapy.

INTERVENTIONS

Hysteroscopy, endometrial biopsy, and transvaginal sonography were performed in all 41 women. In 10 patients, endometrial polyps were removed with the resectoscope.

MEASUREMENTS AND MAIN RESULTS

Irregular bleeding during hormone replacement therapy was associated with atrophic endometrium whenever transvaginal sonography showed endometrial thickness to be less than 4 mm. In patients who developed increased endometrial thickness after hormone replacement therapy, hysteroscopy revealed the presence of endometrial polyps in the uterine cavity. Histopathologic examination of excised polyps revealed cystic or adenomatous hyperplasia confined to these lesions.

CONCLUSIONS

Endometrial polyps can appear in menopausal women receiving hormone replacement therapy despite the presence of progestins to oppose the action of estrogens.

Endometrial thickness assessed by transvaginal ultrasound insufficiently predicts occurrence of hyperplasia during unopposed oestrogen use

In the present study, unopposed oestrogens were given to 184 non-hysterectomized women, for a duration varying from four weeks to 24 months, while the endometrial responses were monitored by transvaginal sonography (TVS) and backed up by endometrial sampling (conducted when the endometrial thickness reached 8 mm (double layer) or more, vaginal bleeding occurred during oestrogen administration, or after one year of unopposed oestrogen use). In cases where the endometrial thickness reached 8 mm or more, progestogens were administered for 12 days. In 64% of the women, administration of progestogen could be postponed until at least the fourth month of treatment under the pre-defined decision criteria. Eleven percent of the patients used oestrogens continuously during the two year study period, without any need of additional progestogen. In total, 338 endometrial biopsies were performed; 16 cases of hyperplasia were detected. In three cases, the corresponding endometrial thickness was below 8 mm (in one case, 5 mm). Endometrial thickness could not consistently predict occurrence of hyperplasia. In eight cases, hyperplasia occurred within 4 months of treatment, and in four cases, within only 2 months (of which only one case could possibly be attributed to previous hormone use and none to endogenous oestrogen production). The rapid occurrence of hyperplasia should be taken into account in studies of quarterly progestogen administration with hormone replacement therapy. It is concluded that postponement of progestogen administration with hormone replacement therapy under guidance of TVS only (without biopsies) would not be adequately safe to be recommended for clinical practice.

Uterine findings by transvaginal sonography during percutaneous estrogen treatment in postmenopausal women

OBJECTIVES

To evaluate the effect of hormone replacement treatment (HRT) with percutaneous estradiol and cyclical peroral medroxyprogesterone acetate (MPA) every month or every third month on the uterus and endometrium of postmenopausal women.

METHODS

Uterine size and endometrial thickness were measured by transvaginal sonography in 159 postmenopausal women before HRT, and after 6 and 12 months on HRT during 9-12 days of the MPA administration periods.

RESULTS

During HRT, uterine size and endometrial thickness increased. The percentage increase in uterine diameter varied between 3.8% and 19.6%, and endometrial thickness varied between 28.7% and 76.4%, being greater in the group receiving MPA every third month than in the groups receiving MPA every month. Myomas grew during the first 6 months on HRT but increased no further during the next 6 months on HRT.

CONCLUSIONS

The increases in uterine size, myomas and endometrial thickness during HRT were moderate and not problematic and occurred mainly during the first 6 months on HRT.

Hormonal and non-hormonal interventions for menopausal symptoms

Recent cohort studies confirm that only flushes, night sweats and vaginal dryness are provenly associated with ovarian failure. Experiments nave demonstrated that these symptoms and insomnia associated with nocturnal vasomotor symptoms are more effectively controlled by oestrogen than placebo. Hormonal interventions include a variety of oestrogen or oestrogen/progestogen regimes. Non-hormonal treatments of flushes include exercise, paced respiration and psychotherapy. After the menopause vaginal atrophy and some urinary symptoms respond to local oestrogen and vaginal dryness in also prevented by lubricants. Libido is not increased by oestrogen therapy but may be improved by testosterone. Depression is common in middle-aged women but is not specifically associated with the hormonal changes occurring at the menopause. Oestrogen therapy may improve and stabilise mood during the peri-menopause but there is no firm evidence that it is effective for depression after the menopause. Arthralgia is not a symptom specific to menopause and experimental evidence concerning the role of oestrogen in the treatment of rheumatoid arthritis is inconclusive. Cognitive function is not related to menopause and measures such as stopping smoking, exercise and maintaining body weight may be partly effective in preventing menopausal symptoms.

Transdermal estrogen with a levonorgestrel-releasing intrauterine device for climacteric complaints: clinical and endometrial responses

OBJECTIVE

Our purpose was to study the effects of intrauterine release of a daily dose of 20 micrograms levonorgestrel by an intrauterine device on climacteric symptoms, bleeding pattern, and endometrial histologic features in postmenopausal women receiving transdermal estrogen replacement therapy.

STUDY DESIGN

Forty parous postmenopausal women were randomly allocated into two groups for 1 year: 20 women receiving a continuous transdermal daily dose of 50 micrograms of estradiol had a levonorgestrel-releasing intrauterine contraceptive device inserted, and the control group of 20 women received a continuous oral dose of 2 mg of estradiol valerate and 1 mg of norethisterone acetate daily. The climacteric symptoms, bleeding patterns, endometrial thickness, and endometrial changes in biopsy samples were analyzed. Serum levels of estradiol in both groups and levonorgestrel levels in the intrauterine device group were also determined.

RESULTS

Both treatment regimens effectively relieved climacteric symptoms. Spotting was more common in the intrauterine contraceptive device group than in the oral therapy group for the first 3 months. After that, the proportion of women without any bleeding was similar in both groups. Two patients in each group dropped out because of bleeding.

CONCLUSION

These preliminary findings suggest that the levonorgestrel-releasing intrauterine contraceptive device is a useful alternative mode of progestin administration for certain selected women receiving estrogen replacement therapy.

Transvaginal ultrasonography for identifying endometrial pathology in postmenopausal women

The objective of this study was to evaluate the usefulness of transvaginal ultrasonography in postmenopausal women with a clinical indication for a dilatation and curettage (D&C). Of the 167 postmenopausal women included in the study, 88% were referred for a D&C because of vaginal bleeding and 12% of the women had other clinical indications such as myomas, gynecological pain or suspected gynecological tumors. Hormone replacement therapy (HRT) was used by 37% of the women. The women were examined with transvaginal ultrasonography before the D&C. The endometrial thickness and texture were used as indicators of endometrial abnormalities. The ultrasonographical findings were related to the histological diagnosis obtained from the D&C. Histologically, 31% of the women had an atrophic endometrium and the corresponding ultrasonographically mean endometrial thickness was 4.6 mm (range 0-14 mm). Endometrial cancer was histologically found in 10% of the women and the endometrial thickness of the malignant endometrium, measured by ultrasonography, was 13.9 mm (range 6-31 mm). All the malignancies were found in the group of women with vaginal bleeding, but only one was in the group of women on HRT. Histologically, endometrial hyperplasia was found in 6.5% of the women and endometrial polyps in 8.5% after the D&Cs. In these postmenopausal women it was demonstrated that if the endometrium was < 6 mm thick, no endometrial cancer was found at histopathological investigation. By using a cut-off point of 6 mm of ultrasonographically measured endometrial thickness for identification of endometrial pathology in our study, at least 50% of the D&Cs could be spared.

Transvaginal sonography of the endometrium in postmenopausal women: monitoring the effect of hormone replacement therapy

BACKGROUND

It is well known that progestins given in sufficient dosage reduce the risk of endometrial cancer and endometrial hyperplasia. It is also not uncommon that patients receiving hormone replacement therapy (HRT) require endometrial biopsy in order to evaluate the effects of oestrogens and progestogens on endometrium. However, endometrial biopsy is often associated with pain and discomfort, and transvaginal sonography has been suggested as a new and painless method of monitoring the effects of HRT on the endometrium.

METHODS

Transvaginal ultrasonography was performed in a series of women on several regimens of HRT immediately prior to endometrial biopsy (Cornier cannula). We correlated the morphology and thickness of the endometrium as assessed by transvaginal ultrasonography with the endometrial histology. Patients were assigned into four groups. The first (n = 15) received 0.6 mg/day of conjugated equine oestrogen (CEE) cyclically and the second (n = 6) received 50 micrograms/day of transdermal oestradiol cyclically. All these groups also received 5 mg of medroxy-progesterone acetate (MPA) sequentially for the last 12 days of HRT, while the third therapy group (n = 7) received 0.625 mg/day of CEE and 5 mg/day of MPA uninterruptedly. The fourth group (n = 8) constituted a treatment-free control group. In total 36 biopsies were taken. Our initial results suggest that endometrial thickness under 4 mm measured by ultrasonography is not associated with endometrial abnormalities and that transvaginal ultrasonographic scanning of the endometrium may be a useful tool in determining which patients require endometrial histologic evaluation and perhaps in detecting those who need adjustment in the progestin dosage.

Ultrasound determination of the effect of progestogens on the endometrium in postmenopausal women receiving hormone replacement therapy

Progestogen challenge tests were performed in 81 postmenopausal women receiving hormone replacement therapy (HRT) with progestogen addition as required. The number of tests carried out totalled 159. The effect of progestogen use on endometrial thickness was determined by vaginosonography. The endometrial shedding caused by progestogen was correlated with the withdrawal bleeding pattern. As expected, in the majority of cases (145 out of 159), progestogen brought about endometrial shedding. In most but not all cases, shedding was attended by withdrawal bleeding. The intensity and the duration of withdrawal bleeding were positively correlated with endometrial shedding. No correlation was found between endometrial shedding and the onset of withdrawal bleeding.