Total Estrogen Research Articles

Transdermal delivery of combined hormonal contraception: a review of the current literature.

The transdermal patch provides an effective and convenient option for hormonal contraception. The patch currently on the US market contains 150 µg norelgestromin and 35 µg ethinylestradiol (EE). The 20 cm2 patch is applied once weekly for 3 weeks, followed by a patch-free week, for a 21–7 cycle. Typical failure rates are similar to that of combined oral contraceptives (COCs). Transdermal delivery results in less peaks and troughs of estrogen, but a higher total estrogen exposure compared with COCs. Though studies show mixed results, the risk of developing venous thromboembolism (VTE) is about twice as high with the patch as with COCs; however, the absolute risk of VTE remains low. The side effect profile is similar to that of COCs, with slightly higher rates of breast tenderness plus a unique adverse effect of application site reactions. Two new patches have been developed, one containing gestodene and EE in Europe and another containing levonorgestrel and EE. Overall, the patch provides an alternative to COCs for women who want autonomy and the benefit of not needing to take a pill daily, with similar efficacy and tolerability.

Association of Estrogen Metabolism with Breast Cancer Risk in Different Cohorts of Postmenopausal Women.

Endogenous estradiol and estrone are linked causally to increased risks of breast cancer. In this study, we evaluated multiple competing hypotheses for how metabolism of these parent estrogens may influence risk. Prediagnostic concentrations of estradiol, estrone, and 13 metabolites were measured in 1,298 postmenopausal cases of breast cancer and 1,524 matched controls in four separate patient cohorts. The median time between sample collection and diagnosis was 4.4 to 12.7 years across the cohorts. Estrogen analytes were measured in serum or urine by liquid chromatography-tandem mass spectrometry. Total estrogen levels (summing all 15 estrogens/estrogen metabolites) were associated strongly and positively with breast cancer risk. Normalizing total estrogen levels, we also found that a relative increase in levels of 2-hydroxylation pathway metabolites, or in the ratio of 2-hydroxylation:16-hydroxylation pathway metabolites, were associated inversely with breast cancer risk. These associations varied by total estrogen levels, with the largest risk reductions occurring in women in the highest tertile. With appropriate validation, these findings suggest opportunities for breast cancer prevention by modifying individual estrogen metabolism profiles through either lifestyle alterations or chemopreventive strategies. Cancer Res; 77(4); 918-25. ©2017 AACR.

Phytoestrogens and sterols in waters with cyanobacterial blooms - Analytical methods and estrogenic potencies

Compounds with estrogenic potencies and their adverse effects in surface waters have received much attention. Both anthropogenic and natural compounds contribute to overall estrogenic activity in freshwaters. Recently, estrogenic potencies were also found to be associated with cyanobacteria and their blooms in surface waters. The present study developed and compared the solid phase extraction and LC-MS/MS analytical approaches for determination of phytoestrogens (8 flavonoids - biochanin A, coumestrol, daidzein, equol, formononetin, genistein, naringenin, apigenin – and 5 sterols - ergosterol, β-sitosterol, stigmasterol, campesterol, brassicasterol) and cholesterol in water. The method was used for analyses of samples collected in stagnant water bodies dominated by different cyanobacterial species. Concentrations of individual flavonoids ranged from below the limit of detection to 3.58 ng/L. Sterols were present in higher amounts up to 2.25 μg/L. Biological potencies of these phytoestrogens in vitro were characterized using the hERα-HeLa-9903 cell line. The relative estrogenic potencies (compared to model estrogen - 17β-estradiol) of flavonoids ranged from 2.25E-05 to 1.26E-03 with coumestrol being the most potent. None of the sterols elicited estrogenic response in the used bioassay. Estrogenic activity was detected in collected field water samples (maximum effect corresponding to 2.07 ng/L of 17β-estradiol equivalents, transcriptional assay). At maximum phytoestrogens accounted for only 1.56 pg/L of 17β-estradiol equivalents, contributing maximally 8.5% of the total estrogenicity of the water samples. Other compounds therefore, most likely of anthropogenic origin such as steroid estrogens, are probably the major drivers of total estrogenic effects in these surface waters.

Estrogen Transport in Surface Runoff from Agricultural Fields Treated with Two Application Methods of Dairy Manure.

This study compares two methods of dairy manure application-surface broadcast and shallow disk injection-on the fate and transport of natural estrogens in surface runoff from 12 field plots in central Pennsylvania. Ten natural surface runoff events were sampled over a 9-mo period after fall manure application. Results show that the range of estrogen concentrations observed in surface runoff from the broadcast plots was several orders of magnitude higher (>5000 ng L) than the concentrations in runoff from the shallow disk injection plots (<10 ng L). Additionally, the transport dynamics differed, with the majority of the estrogen loads from the surface broadcast plots occurring during the first rainfall event after application, whereas the majority of the loads from the shallow disk injection plots occurred more than 6 mo later during a hail storm event. Total estrogen loads were, on average, two orders of magnitude lower for shallow disk injection compared with surface broadcast. Independent of the method of manure application, 17α-estradiol and estrone were preserved in the field for as long as 9 mo after application. Overall, injection of manure shows promise in reducing the potential for off-site losses of hormones from manure-amended soils.

Sex hormone-binding globulin regulation of androgen bioactivity in vivo: validation of the free hormone hypothesis.

Sex hormone-binding globulin (SHBG) is the high-affinity binding protein for androgens and estrogens. According to the free hormone hypothesis, SHBG modulates the bioactivity of sex steroids by limiting their diffusion into target tissues. Still, the in vivo physiological role of circulating SHBG remains unclear, especially since mice and rats lack circulating SHBG post-natally. To test the free hormone hypothesis in vivo, we examined total and free sex steroid concentrations and bioactivity on target organs in mice expressing a human SHBG transgene. SHBG increased total androgen and estrogen concentrations via hypothalamic-pituitary feedback regulation and prolonged ligand half-life. Despite markedly raised total sex steroid concentrations, free testosterone was unaffected while sex steroid bioactivity on male and female reproductive organs was attenuated. This occurred via a ligand-dependent, genotype-independent mechanism according to in vitro seminal vesicle organ cultures. These results provide compelling support for the determination of free or bioavailable sex steroid concentrations in medicine, and clarify important comparative differences between translational mouse models and human endocrinology.

Prediction of Estrogenic Bioactivity of Environmental Chemical Metabolites.

The US Environmental Protection Agency's (EPA) Endocrine Disruptor Screening Program (EDSP) is using in vitro data generated from ToxCast/Tox21 high-throughput screening assays to assess the endocrine activity of environmental chemicals. Considering that in vitro assays may have limited metabolic capacity, inactive chemicals that are biotransformed into metabolites with endocrine bioactivity may be missed for further screening and testing. Therefore, there is a value in developing novel approaches to account for metabolism and endocrine activity of both parent chemicals and their associated metabolites. We used commercially available software to predict metabolites of 50 parent compounds, out of which 38 chemicals are known to have estrogenic metabolites, and 12 compounds and their metabolites are negative for estrogenic activity. Three ER QSAR models were used to determine potential estrogen bioactivity of the parent compounds and predicted metabolites, the outputs of the models were averaged, and the chemicals were then ranked based on the total estrogenicity of the parent chemical and metabolites. The metabolite prediction software correctly identified known estrogenic metabolites for 26 out of 27 parent chemicals with associated metabolite data, and 39 out of 46 estrogenic metabolites were predicted as potential biotransformation products derived from the parent chemical. The QSAR models estimated stronger estrogenic activity for the majority of the known estrogenic metabolites compared to their parent chemicals. Finally, the three models identified a similar set of parent compounds as top ranked chemicals based on the estrogenicity of putative metabolites. This proposed in silico approach is an inexpensive and rapid strategy for the detection of chemicals with estrogenic metabolites and may reduce potential false negative results from in vitro assays.

Parturition induction in ewes by a progesterone receptor blocker, aglepristone, and subsequent neonatal survival: Preliminary results

The clinical effects of aglepristone treatment to induce parturition in ewes and their newborns were reported. Three experimental groups were defined: group AG5 (n = 5), group AG10 (n = 5), and group CG (n = 5) in which ewes were injected twice with 5, 10 mg/kg of aglepristone, and saline solution of ewes, respectively. Different parameters associated with parturition in ewes and their newborns were investigated. Serum progesterone, oxytocin, and free and conjugated total estrogens were measured after treatments until parturition. No statistical difference was found from first aglepristone administration to onset of lambing between AG5 and AG10 (23.90 ± 6.20, 40.00 ± 6.71 hours). Parturition induction in two groups shortened the gestational length significantly compared with the control group (P = 0.003). Dystocia was observed in two ewes in group AG10. The placental weight showed statistically significant difference only between the AG10 and CG (P = 0.039), but no difference was observed in the placental expulsion period between the groups. Decrease in food consumption 24 to 36 hours after parturition in all ewes and skin necrosis in an ewe in group AG5 were observed. Progesterone concentration was significantly lower in AG5 than that in ewes in group AG10 and CG (P < 0.05). No difference was observed in concentrations of free total estrogens and oxytocin between groups. The body temperature of lambs was significantly different between AG10 and CG groups both right after (P = 0.011) and 12 hours after parturition (P = 0.014). The lambs in CG had the highest mean birth weight (4.29 ± 0.28 kg), which was significantly different from the induced groups. No significant difference of blood pH and blood gases values between groups was identified both at birth and 12 hours after parturition for lambs. Significant differences could clearly be observed in total protein and blood urea nitrogen and total protein findings 12 hours after parturition (P < 0.05), whereas no difference was found in blood glucose, albumin, inorganic phosphor, triglyceride, or total cholesterol parameters. The results of this study show that the administration of aglepristone to induce parturition can precisely control lambing time without any side effects in either mothers or lambs.

Parent and conjugated estrogens and progestagens in surface water of the Santa Ana River: Determination, occurrence, and risk assessment.

The present study investigated the occurrence of 13 parent and conjugated estrogens and progestagens in surface water of the Santa Ana River. With the exception of the synthetic hormones 17α-ethynylestradiol and mestranol, other compounds were detected at least twice at 10 representative sites, with the ubiquitous estrone (E1) and 17β-estradiol-3-sulfate as the dominant compounds quantified (0.24-6.37 ng/L and 0.49-9.25 ng/L, respectively). Sites near dairy farms exhibited high levels of conjugates, whereas those close to a sewage treatment plant (STP) effluent outlet displayed relatively high concentrations of E1. Principle component analysis coupled with multiple linear regression revealed dairy farms and the STP as the 2 significant contamination sources, accounting for 69.9% and 31.1% of the total hormone burden, respectively. Risk assessment results suggested E1 and 17β-estradiol (E2) as the 2 hormones with the largest risks to aquatic organisms, and which combined, contributed >90% of the total estrogenicity. Most of the sites investigated showed that E1 and E2 posed a medium risk (0.1 < risk quotient < 1), whereas each induced a high risk (risk quotient >1) at sites severely impacted by the STP and dairy farms. These results suggest that river health would benefit from effective treatment of waste at the STP and dairy farms prior to discharge. Environ Toxicol Chem 2016;35:2657-2664. © 2016 SETAC.

Sexual dimorphism in the glucose homeostasis phenotype of the Aromatase Knockout (ArKO) mice

We investigated the effects of estrogens on glucose homeostasis using the Aromatase Knockout (ArKO) mouse, which is unable to convert androgens into estrogens. The ArKO mouse is a model of total estrogen ablation which develops symptoms of metabolic syndrome.To determine the development and progression of whole body state of insulin resistance of ArKO mice, comprehensive whole body tolerance tests were performed on WT, ArKO and estrogen administrated mice at 3 and 12 months of age. The absence of estrogens in the male ArKO mice leads to hepatic insulin resistance, glucose and pyruvate intolerance from 3 to 12 months with consistent improvement upon estrogen treatment. Estrogen absence in the female ArKO mice leads to glucose intolerance without pyruvate intolerance or insulin resistance. The replacement of estrogens in the female WT and ArKO mice exhibited both insulin sensitizing and resistance effects depending on age and dosage.In conclusion, this study presents information on the sexually dimorphic roles of estrogens on glucose homeostasis regulation.

Estrogenicity of captive southern white rhinoceros diets and their association with fertility

The captive southern white rhinoceros (SWR) population is not currently self-sustaining, primarily due to poor or absent reproduction of captive-born (F1+) females. In this study, we investigate the role of dietary phytoestrogens in this reproductive phenomenon by characterizing activation of SWR estrogen receptors (ESRs) 1 and 2 by diet items from nine North American institutions and comparing female SWR fertility to total diet estrogenicity. Of the diet items tested, alfalfa hay and soy and alfalfa-based commercial pellets were found to be the most potent activators of SWR ESRs. In contrast, most grass hays tested were not estrogenic. The estrogenicity of total diets varied across the institutions surveyed and the degree of diet estrogenicity was positively associated with the percentage of the total diet comprised by pellets. Comparisons of fertility records of the institutions surveyed showed no significant relationship between diet estrogenicity and fertility for female SWR conceived or born in the wild (F0). However, for F1+ females, there was a significant negative relationship between institutional diet estrogenicity and fertility. Taken together, these data suggest that developmental exposure to phytoestrogens may be the cause of poor fertility in captive-born female SWR. Whether the low fertility of the current population of captive-born female SWR is permanent or can be reversed by removing phytoestrogens from the diet remains unclear. However, our findings suggest that in order for the SWR population to become self-sustaining, the development and feeding of low phytoestrogen diets should be strongly considered.

The Effects of a Multi-Ingredient Performance Supplement on Hormonal Profiles and Body Composition in Male College Athletes.

Periods of intense training can elicit an acute decline in performance and body composition associated with weakened hormone profiles. This study investigated the effects of a multi-ingredient performance supplement (MIPS) on body composition and hormone levels in college athletes following a six-week training protocol. Twenty male college athletes were equally assigned to MIPS and placebo (PLA) groups for supplementation (three pills, twice daily) in conjunction with resistance training and specialized sports training (e.g., nine total sessions/week) for six weeks. Dual Energy X-ray Absorptiometry determined body composition at weeks 0 and 6. Serum samples collected at weeks 0 and 6 determined free testosterone (FT), total testosterone (TT), IGF-1 and total estrogen (TE) levels. PLA experienced a significant decline in lean body mass (LBM) (−1.5 kg; p < 0.05) whereas the MIPS sustained LBM. The MIPS increased TT 21.9% (541.5 ± 48.7 to 639.1 ± 31.7) and increased FT 15.2% (13.28 ± 1.1 to 15.45 ± 1.3 ng/dL) (p < 0.05). Conversely, PLA decreased TT 7.9% (554.5 ± 43.3 to 497.2 ± 39.1 ng/dL), decreased FT 17.4% (13.41 ± 1.8 to 11.23 ± 2.55 ng/dL), and decreased FT:E 12.06% (p < 0.05). These findings suggest the MIPS can prevent decrements in LBM and anabolic hormone profiles during intense training periods.

Fate of Conjugated and Free Estrogens in Swine Manure Collected from areas Housing Piglets, Pregnant Sows and Finisher Pigs

Occurrence and fate of estrogens and their metabolites were studied in pig manure collected during winter and summer seasons from sites housing piglets (Nursery (Nur)-manure), pregnant and nursing sows (PS manure) and finisher pigs (FPig manure). The liquid and solid fractions of manure were analyzed for (1) total solids (TS), volatile solids (VS) and total organic carbon (TOC), (2) E coli and M fujisawaense enumeration, (3) total and individual estrogens and (4) estrogenic activity. This study showed that VS and OC values, E coli and M fujisawaense enumerations, estrogen concentrations and estrogenic activity exhibited the following pattern: Nur-manure &lt;&lt; FPig-manure &lt; PS-manure. The values for summer and winter Nur-manure did not differ significantly, while the values in summer PS-manure or FPig manure samples were significantly higher than values in corresponding winter samples. Although, estrogens distributed between liquid and solid fractions of manure, concentrations of free, but not conjugated, estrogens depended on manures’ TOC values: an increase in TOC associated with an increase in free estrogen concentrations in liquid manure. However, an increase in TOC decreased the bacterial population in manure liquid by increasing their translocation from liquid into the in solids and ensuing bacterial stabilization. This may increase estrogens’ deconjugation and/or degradation. Estrone (E1) sulfate (sE1), free E1 (fE1), E1 glucuronide (gE1) and E1 metabolites were major steroids present in Nur- and PS-manure, while fE2 and gE2 were predominant estrogens in FPig-manure. In total, the winter estrogen load in liquid was 5.1 mg/L and the load in solid was 4.93 mg/kg. Assuming that 2.3 x 108 kg of manure is produced in the USA per day, approximate hormone load will be 2.3 tons/day. However, manure contains microorganisms that hydrolyze estrogens, thus actual hormone load will be considerably lower.

Responsiveness of prepubertal crossbred bull calves to exogenous GnRH and its impact on reproductive hormones under tropical conditions.

This study investigated the age related variations in luteinizing hormone (LH), androstenedione, testosterone, and total estrogens response to exogenous gonadotropin-releasing hormone (GnRH) in Holstein–Friesian (HF) × Tharparkar bull calves. Fifteen bull calves were selected and, based on their age, were divided into Group I (14–16 months, n = 5), Group II (9–12 months, n = 5), and Group III (6–8 months, n = 5). All bull calves were administered with 10 µg of GnRH intramuscularly. Blood samples were collected at an interval of 30 min commencing 1 h prior to GnRH treatment until 4 h post-GnRH treatment and thereafter, at an interval of 1 h for the next 3 h. Endocrine response in terms of pretreatment values, peak values, area under curve, and time taken to attain peak values for LH, androstenedione, testosterone, and total estrogens was evaluated in all the bull calves. Significant differences were observed in pretreatment values, peak concentrations, and area under curve for androstenedione and testosterone between the groups; with response being higher in Group I bull calves. The results indicated that the HF × Tharparkar bull calves of 14 months age and above respond to exogenous GnRH by secreting significant amounts of testosterone.

Follicle Diameter and Systemic Hormone Interrelationships during Induction of Follicle Collapse with Intrafollicular Prostaglandin E2 and F2α in Mares.

The objectives were to determine: (i) whether intrafollicular administration of PGE2 and PGF2α to mares would hasten follicle collapse and (ii) the differences in reproductive hormone characteristics in mares with spontaneous and prostaglandin-induced follicle collapses. Six mares were followed for two oestrous cycles each: when the mares reached a follicle diameter of 30-35 mm and showed mild-to-moderate endometrial oedema, mares were administered a single 0.5 ml dose containing 500 μg PGE2 and 125 μg PGF2α (treatment cycle) or a placebo (0.5 ml of water for injection; control cycle) into the preovulatory follicle (Hour 0). Blood samples were collected, and serial ultrasound examinations were performed until follicle collapse. Treated mares showed follicle collapse significantly earlier (20.0 ± 5.9 h) than the control mares (72.0 ± 10.7 h). The LH, progesterone, total oestrogens and oestradiol concentrations did not differ between groups; however, the progesterone concentration increased more between 48 and 72 h after follicle injection in the treatment compared to the control cycles (P < 0.05). In conclusion, intrafollicular treatment with PGE2 and PGF2α hastened follicle collapse in mares without the simultaneous use of an inductor of ovulation; despite the early induction of follicle collapse, the profiles of LH and oestradiol were not altered. This study provides information on the role of prostaglandins (PGs) in the process of follicle wall rupture and collapse and suggests that this may happen even before the beginning of the sharp rise in circulating LH at the final stage of the ovulatory surge.

Significant alterations of serum hormone levels in the spermatic vein plexus of patients with varicoceles

The objective of this study was to evaluate the level of hormone variation between the peripheral blood and spermatic vein plexus in patients with varicoceles. A total of 23 patients diagnosed with varicoceles were enrolled in the study. All patients underwent a testicular artery-sparing microsurgical varicocelectomy. During the operation, a blood sample from the ipsilateral spermatic vein plexus and a peripheral blood sample were collected. A radioimmunoassay was performed to determine the total testosterone, free testosterone, dihydrotestosterone and oestradiol levels. An enzyme-linked immunosorbent assay was performed to determine the albumin level. The mean age of the patients was 32.3±9.3years. Compared with the hormone level in the peripheral blood, the total testosterone, free testosterone, dihydrotestosterone, and oestrogen levels were significantly increased in the left or right spermatic vein plexus (P<0.05). There were no differences in the albumin levels in the peripheral blood and spermatic vein plexus (P>0.05). The mean total testosterone, free testosterone, dihydrotestosterone, and oestradiol levels in the left spermatic vein plexus were 10.8-fold, 29.0-fold, 2.0-fold, and 26.6-fold those of the peripheral blood. The hormone concentration in the spermatic vein plexus was significantly higher than that in the peripheral blood in patients with varicoceles.

Effects of black cohosh on estrogen biosynthesis in hippocampus of non-human primates ex vivo in vitro and in human neuroblastoma cells in vitro

BackgroundEstrogens have neuroprotective properties. The aim of the study was to assess the impact of an isopropanolic extract of Cimicifuga racemosa (iCR), 17ß-estradiol (E2), testosterone (T) and Tibolone’s 3α-OH metabolite (Org4094) on local estrogen formation in hippocampus tissue from non-human primates ex vivo in vitro and human neuroblastoma cells (SH-SY5Y) in vitro.MethodsSH-SY5Y cells were incubated in RPMI 1640 medium containing 5 % steroid-depleted fetal calf serum for 3 days, and subsequently incubated in absence or presence of iCR at 10 μg/ml (n = 5) and 1 μg/ml (n = 5), E2 at 10−8 M (n = 5), and 10−6 M (n = 5), or T at 10−8 M (n = 5), and 10−6 M (n = 5), respectively, at 37 °C for either 24 h or directly in cell extracts. Hippocampus tissue from healthy female cynomolgus macaques (n = 14) was homogenized and treated with iCR, E2 and Org4049 accordingly. STS activity was evaluated by incubating homogenized brain cells and tissue with [3H]-estrone sulfate and separating the products estrone (E1) and E2 by thin layer chromatography. STS activity was expressed as total estrogen formation (E1 + E2) fmol/mg of protein/min. Statistical comparisons were made using unpaired T-Test for comparing two sets of data and ANOVA to compare many groups at once. A p value < 0.05 was considered to be significant different.ResultsBasal total estrogen formation was significantly higher in proliferative SH-SY5Y cells (1350.06 ± 109 E1 + E2 fmol/mg of protein/min) compared to hippocampus tissue (37.83 ± 3.9 E1 + E2 fmol/mg of protein/min; p < 0.01). ICR exerted a bidirectional action with an immediate strong inhibitory effect being followed by a stimulation of STS activity (85 % increase). E2 had a bidirectional dose-dependent long-term effect on STS activity (−23 % reduction and 18 % increase). T and Org4094 had an immediate strong inhibitory effect on STS activity that further maintained with 24 h T treatment (30 % decrease).ConclusionsLocal estrogen formation within brain cells and tissue may be modulated by black cohosh, 17ß-estradiol, testosterone, and Tibolone’s 3α-OH metabolite, respectively. The clinical implication of this finding has to be elucidated.

Analysis of 17-β-estradiol and 17-α-ethinylestradiol in biological and environmental matrices — A review

The estrogens 17-β-estradiol (E2) and 17-α-ethinylestradiol (EE2) are reported as highly endocrine-disrupting agents, being recently included in an EU watch list regarding emerging aquatic pollutants. Therefore, the monitoring of these chemicals in the different environmental compartments assumes great importance. Moreover, due to the possible adverse effects on living beings, their occurrence on animal tissues and fluids must also be addressed. In recent years, a significant number of studies have described and proposed different analytical methodologies to detect and/or quantify E2 and EE2 mostly in environmental aqueous samples, including sludge and sediments and also in biological matrices such as plasma and tissues. Taking into account the complexity of real matrices and that both estrogens are generally present at trace levels, the development of accurate and reliable techniques for their determination can be quite a challenge. The present review aims at describing the main characteristics of the analytical methods recently used for E2 and EE2 determination in environmental and biological samples. The steps for sample preparation such as analytes extraction, preconcentration and clean-up are discussed and the instrumental based analytical techniques are compared. Furthermore, the application of biological tools to determine the total estrogenicity of environmental samples, as well as their potential combination with instrumental analyses, is highlighted.

Relationship Between Female Reproductive Factors and Choroidal Nevus in US Women: Analysis of Data From the 2005-2008 National Health and Nutrition Examination Survey.

Choroidal nevus is a precursor for uveal melanoma and there are no known risk factors besides white race. Female sex hormones have been hypothesized to play a role in the pathogenesis of uveal melanoma. To explore the association between female reproductive factors and choroidal nevus in the US adult female population. Cross-sectional, population-based study of 2505 US women aged 40 years or older from the 2005-2008 National Health and Nutrition Examination Survey. The women completed the reproductive health questionnaire and underwent retinal imaging. The analysis was conducted in April 2015. Age at menarche, oral contraceptive use, pregnancy, parity, age at first and last births, age at menopause, hysterectomy, oophorectomy, hormone therapy use, and body mass index (calculated as weight in kilograms divided by height in meters squared). Choroidal nevus on retinal imaging. The mean age of participants was 56.5 years, and the racial/ethnic distribution was 76.9% white, 10.1% African American, 8.4% Hispanic, and 4.8% other. The weighted prevalence of choroidal nevus was 4.5%. Premenopausal women who first gave birth before age 20 years had more than 4 times higher odds of choroidal nevus than those who first gave birth after age 35 years (odds ratio [OR], 4.16; 95% CI, 1.29-13.45; P = .02), and premenopausal women who gave birth to their last child before age 25 years had nearly 5 times higher odds of choroidal nevus than those who gave birth to their last child after age 35 years (OR, 4.89; 95% CI, 1.15-20.74; P = .03). These relationships were independent of total parity and years between the first and last births. The odds of choroidal nevus in postmenopausal women who were overweight and obese were 2 times higher than in postmenopausal women with normal body mass index (OR, 2.11; 95% CI, 1.19-3.76; P = .01 for overweight and OR, 1.92; 95% CI, 1.13-3.25; P = .02 for obese). The association between choroidal nevus and earlier start and end to childbearing in premenopausal women and obesity in postmenopausal women suggests that this relationship could be partially mediated via increased total lifetime unopposed estrogen. Clinicians should have an increased index of suspicion for choroidal nevus and choroidal melanoma in this population.

Investigation of the association between the fecal microbiota and breast cancer in postmenopausal women: a population-based case-control pilot study.

We investigated whether the gut microbiota differed in 48 postmenopausal breast cancer case patients, pretreatment, vs 48 control patients. Microbiota profiles in fecal DNA were determined by Illumina sequencing and taxonomy of 16S rRNA genes. Estrogens were quantified in urine. Case-control comparisons employed linear and unconditional logistic regression of microbiota α-diversity (PD_whole tree) and UniFrac analysis of β-diversity, with two-sided statistical tests. Total estrogens correlated with α-diversity in control patients (Spearman Rho = 0.37, P = .009) but not case patients (Spearman Rho = 0.04, P = .77). Compared with control patients, case patients had statistically significantly altered microbiota composition (β-diversity, P = .006) and lower α-diversity (P = .004). Adjusted for estrogens and other covariates, odds ratio of cancer was 0.50 (95% confidence interval = 0.30 to 0.85) per α-diversity tertile. Differences in specific taxa were not statistically significant when adjusted for multiple comparisons. This pilot study shows that postmenopausal women with breast cancer have altered composition and estrogen-independent low diversity of their gut microbiota. Whether these affect breast cancer risk and prognosis is unknown.

Association of estrogen measurements in serum and urine of premenopausal women.

We evaluated conjugated and unconjugated urinary estrogen metabolites as surrogate biomarkers for serum levels of unconjugated E1 and E2 in premenopausal women. Repeated blood and urine samples were analyzed for estrogens and their metabolites using radioimmunoassays and liquid chromatography/mass spectrometry. The strongest correlation (r = 0.39) was observed between serum E1 and urinary E1 and E2. The correlations of urinary E2 (r = 0.35), E1 (r = 0.29), all E2 metabolites (r = 0.30), all E1 metabolites (r = 0.23) and total estrogens (r = 0.26) with serum E2 were only moderate although statistically significant. All correlations were substantially stronger for Whites than Asians. Urinary E2 emerged as the best predictor for serum E1 and E2, but the large intra-subject variability in urinary estrogen levels limits its use as a biomarker.