Menstrual bleeding patterns in pre- and perimenopausal women: a population-based prospective diary study

The significance of "atrophic endometrium" in women with postmenopausal bleeding

We evaluated the interpretation of atrophic endometrium (AE) histology as the most common cause for postmenopausal bleeding (PMB). This theory has been accepted for several generations by gynecologists and gynecologic oncologists and has been published in past and current major gynecology textbooks. In our review of the literature, we did not find sufficient histological or clinical proof for this concept. In our view, AE is not a cause of PMB and we back this up with a review of old and current medical literature. The old studies are based on information which was obtained prior to the existence of transvaginal sonogram, sonohysterogram and hysteroscopy. Focal lesions are notorious for being missed by endometrial sampling and curettage. Recent studies show that focal endometrial lesions are a crucial cause for PMB and some of those lesions can harbor cancer. In our opinion, AE is the most common histology found because it is physiologic and a ubiquitous finding in postmenopausal women, but it is not a cause of PMB. Referring to AE as a cause of PMB may result in misdiagnosis of cancer, management delay and unnecessary intervention. To avoid misdiagnosis of cancer, transvaginal sonogram should be considered in all women with PMB and AE on pathology. If endometrial thickness is found, AE is unlikely to be the cause of the PMB and further workup is warranted to reveal the true etiology for the bleeding.

Comparison between Different Diagnostic Strategies in Low-Risk Reproductive Age and Pre-Menopausal Women Presenting Abnormal Uterine Bleeding

Abnormal uterine bleeding (AUB) is a common symptom in the female population, with an estimated prevalence of 10 to 30% in fertile age and up to 90% in perimenopausal women. In most cases, AUB is due to a benign cause. However, it can also be a symptom of atypical endometrial hyperplasia or endometrial cancer, a more common disease during menopause which can also affect women in their reproductive age. Considering the high prevalence of this symptom an appropriate diagnostic algorithm is needed. Concerns about the risks, pain, and stress associated with an endometrial biopsy and its impact on the healthcare system make the choice of AUB diagnostic strategy extremely relevant. Even if the scientific community agrees on the definition of AUB, International Guidelines show some differences in the management of women of reproductive age with AUB, especially regarding the age cut-off as an independent indication for endometrial biopsy. This study compared different diagnostic strategies to identify a diagnostic pathway with high sensitivity and specificity but low impact on the health system's resources. The analysis was based on three diagnostic algorithms defined as part of the guidelines of leading scientific societies. Women of reproductive age with AUB (n = 625) and without risk of endometrial cancer were included in the study. Results showed that the best criterion to investigate AUB in women at low risk of endometrial cancer is not age cut-off but the presence or absence of focal endometrial pathology at the ultrasound and the response to the progestin therapy. This approach makes it possible to perform fewer outpatient hysteroscopic biopsies without excluding positive cases from the examination.

Endometrial thickness cut-off value by transvaginal ultrasonography for screening of endometrial pathology in premenopausal and postmenopausal women

Objective

To assess the clinical usefulness and diagnostic accuracy of ultrasonographic measurement of endometrial thickness (ET) in women with endometrial hyperplasia or cancer (EH+).

Methods

This retrospective cohort study included 29,995 consecutive women who underwent transvaginal ultrasonography (TVS) for an incidental finding of a thickened endometrium at the health screening and promotion center at Asan Medical Center between 2006 and 2010. Among 959 patients with endometrial abnormalities, 92 patients were included in this study. A total of 867 patients were excluded: 416 were lost to follow-up; 263 did not undergo endometrial biopsy; 155 had endometrial polyps; 17 had submucosal myomas; and 16 had insufficient tissue samples. Endometrial histology was the reference standard for calculating accuracy.

Results

Of the 92 patients, 78 (84.8%) had normal pathology, while 14 (15.2%) had endometrial pathology (EH+), including 5 patients (35.7%) with simple hyperplasia without atypia, 3 (21.4%) with complex hyperplasia, and 6 (42.9%) with endometrial carcinoma, all stage Ia. The area under the receiver-operating characteristic curve was 0.75 (95% confidence interval [CI], 0.593-0.906). The cut-off value for ET was 8 mm, indicating that TVS ET had a fair accuracy in diagnosing carcinoma, had a sensitivity of 100% (95% CI, 62.9-100.0%) and a specificity of 24.3% (95% CI, 15.2-36.3%).

Conclusion

TVS is useful for detecting EH+, with a cut-off value for ET of 8 mm having a high sensitivity for detecting endometrial pathologies and the ability to identify women highly unlikely to have EH+, thereby avoiding more invasive endometrial biopsy.

Menstrual Cycle Changes as Women Approach the Final Menses: What Matters?

Increased variability in menstrual cycle length marks the onset of the menopausal transition, with the likelihood of long cycles increasing as women approach menopause. This article describes the STRAW+10 bleeding criteria for recognizing onset of the early and late menopausal transition, as well as the specific bleeding changes a woman may experience during this life stage, including how women's bleeding experiences differ. The high probability of episodes of excessive and prolonged bleeding as women approach their final menstrual period is documented, as is the continuing probability of ovulation as women reach their final menstrual period.

Quantitative bias analysis for epidemiological associations of perfluoroalkyl substance serum concentrations and early onset of menopause

An association between increased serum concentrations of perfluoroalkyl substances (PFAS) such as perfluorooctane sulfonate (PFOS) and perfluorooctanoate (PFOA) and early menopause has been reported (Knox et al., 2011; Taylor et al., 2014). This association may be explained by the fact that women who underwent menopause no longer excrete PFAS through menstruation. Our objective was to assess how much of the epidemiologic association between PFAS and altered timing of menopause might be explained by reverse causality. We extended a published population life-stage physiologically-based pharmacokinetic (PBPK) model of PFOS and PFOA characterized by realistic distributions of physiological parameters including age at menopause. We then conducted Monte Carlo simulations to replicate the Taylor population (Taylor et al., 2014) and the Knox population (Knox et al., 2011). The analysis of the simulated data overall showed a pattern of results that was comparable to those reported in epidemiological studies. For example, in the simulated Knox population (ages 42-51) the odds ratio (OR) for menopause in the fifth quintile of PFOA compared to those in the first quintile was 1.33 (95% CI 1.26-1.40), whereas the reported OR was 1.4 (95% CI 1.1-1.8). Using our model structure, a substantial portion of the associations reported can be explained by pharmacokinetics.

Endometrial evaluation with transvaginal ultrasonography for the screening of endometrial hyperplasia or cancer in premenopausal and perimenopausal women

Objective

The aim of our study is to determine clinical factors and sonographic findings associated with endometrial hyperplasia or cancer (EH+) in premenopausal and perimenopausal women.

Methods

A total of 14,340 transvaginal ultrasonography examinations of 9,888 healthy premenopausal and perimenopausal women were included in this retrospective study. One hundred sixty-two subjects underwent endometrial biopsy based on abnormal uterine bleeding (AUB), sonographic endometrial abnormalities (thickened endometrium, endometrial mass, or endometrial stripe abnormality), or both. The clinical factors and sonographic endometrial abnormalities were evaluated with regard to EH+.

Results

Histologically verified EH+ was found in fourteen subjects (8.6%); ten cases of endometrial hyperplasia (EH) without atypia, three cases of EH with atypia (AEH), and one case of endometrial cancer. Neither clinical factors nor AUB were associated with EH+ (P=0.32) or AEH+ (P=0.72). Of sonographic findings, endometrial stripe abnormality was significantly associated with EH+ (P=0.003) and marginally associated with AEH+ (P=0.05), but a thickened endometrium was not associated with EH+ (P=0.43).

Conclusion

Endometrial stripe abnormality is a significant factor to predict EH+ in healthy premenopausal and perimenopausal women with and without AUB. However, simple measurement of endometrial thickness has a limited role in this capacity.

Bleeding patterns during the menopausal transition in the multi-ethnic Study of Women's Health Across the Nation (SWAN): a prospective cohort study

OBJECTIVE

Previous studies describing menses duration and heaviness of flow during the menopausal transition (MT) have been short in duration and limited to white women. We estimated the frequency of and risk factors for prolonged bleeding, spotting and heavy bleeding during the MT in an ethnically diverse population.

DESIGN

Prospective community-based cohort study.

SETTING USA

southeastern Michigan, northern California and Los Angeles, California.

POPULATION

A total of 1320 midlife women who participated in the Study of Women's Health Across the Nation (SWAN) Menstrual Calendar Substudy. Participants included African-American, white, Chinese, and Japanese women.

METHODS

Women completed daily menstrual calendars from 1996 to 2006, and provided information on hormone therapy, smoking and physical activity. Annual measures included height and weight. Kaplan-Meier survival analysis and multivariable regression were used to analyse the data.

MAIN OUTCOME MEASURES

Menses of 10+ days, spotting of 6+ days, heavy bleeding of 3+ days.

RESULTS

At least three occurrences of menses 10+ days was reported by 77.7% (95% confidence interval [95% CI] 56.7-93.2), of 6+ days of spotting by 66.8% (95% CI 55.2-78.0) and of 3+ days of heavy bleeding by 34.5% (95% CI 30.2-39.2) of women. Menses of 10+ days, 6+ days of spotting, and 3+ days of heavy bleeding were associated with MT stage, uterine fibroids, hormone use and ethnicity. Body mass index was associated with 3+ days of heavy bleeding.

CONCLUSIONS

These data provide clinicians and women with important information about the expected frequency of prolonged and heavy bleeding and spotting during the menopausal transition that may facilitate clinical decision making.

Menstruation and the menopausal transition

This paper characterizes changes in menstrual bleeding during perimenopause,including bleeding changes that represent markers of the menopausal transition. Recent results from the Study of Women's Health Across the Nation and other cohort studies are reviewed. Emerging data describing subpopulation differences in the transition experience are highlighted. When treating women in the midlife, clinicians should pay careful attention to medical factors, including both conditions and treatments, that may increase menstrual blood loss or alter menstrual cycle characteristics sufficiently to obscure the onset of the menopausal transition or the final menstrual period.

First assessment of menstrual cycle function and reproductive endocrine status in Samoan women

BACKGROUND

American Samoa and Samoa are now characterized by one of the world's highest levels of adult overweight and obesity. Our objective was to investigate patterns of menstrual cyclicity reported by Samoan women and examine the relationship to adiposity and select hormone levels.

METHODS

A cross-sectional analysis was performed among Samoan women, aged 18-39 years (n = 322), using anthropometric and biomarker measures of adiposity and reproductive health, including insulin, adiponectin, testosterone, sex hormone-binding globulin, free androgen index (FAI) and mullerian-inhibiting substance (MIS). Menstrual regularity was assessed from self-reported responses. Multivariable models were estimated to adjust for potential confounding of the associations between menstrual patterns and other measures.

RESULTS

A high proportion of the women (13.7%) reported oligomenorrhea or amenorrhea (OM/AM). More than three-quarters, 80.7%, of women were either overweight or obese, using Polynesian-specific criteria, and OM/AM was significantly associated with higher BMI. Abdominal circumference and insulin levels were significantly higher, and adiponectin levels were lower, in those who reported OM/AM versus regular menstruation. The FAI was higher in women with increased BMI. MIS levels declined with age, more slowly in those reporting OM/AM.

CONCLUSIONS

Self-reported OM/AM was associated with an elevated BMI, abdominal adiposity and serum insulin, and with reduced adiponectin levels. These findings support a high rate of metabolic syndrome, and perhaps PCOS and reproductive dysfunction, among Samoan women.

The length of perimenopausal menstrual cycles increases later and to a greater degree than previously reported

OBJECTIVE

To demonstrate that the perimenopausal increase in menstrual cycle length presented by Treloar et al. was biased by misidentified menopause dates, mean values classified by calendar year, and exclusion of menstrual cycles straddling two calendar years; and to use the revised data to investigate women's experiences of longer perimenopausal cycles.

DESIGN

Secondary analysis of prospectively collected menstrual cycle data.

SETTING

Center for Population and Health, Georgetown University.

PATIENT(S)

One hundred twenty white, college-educated, US women in the Tremin Research Program on Women's Health.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

Mean cycle length and time spent in >40-day cycles, by year before menopause.

RESULT(S)

Mean estimates for each of the 4 years before menopause were 30.48, 35.02, 45.15, and 80.22 days, respectively, compared with the original analysis: 33.60, 43.91, 55.87, and 54.58 days. In the year before menopause, the majority of women spent >or=75% of their time in cycles >40 days long.

CONCLUSION(S)

Treloar's estimates of mean cycle length were biased. Long cycles occurred throughout perimenopause, but the largest increase in mean cycle length did not occur until the final year before menopause. New estimates of the time spent in cycles >40 days may be useful clinically as well as epidemiologically for assessing menopausal onset and symptomatology.