Relation of luteinizing hormone levels to body mass index in premenopausal women

Comparative efficacy of exercise, diet and/or pharmacological interventions on BMI, ovulation, and hormonal profile in reproductive-aged women with overweight or obesity: a systematic review and network meta-analysis

BACKGROUND

The increasing prevalence of obesity worldwide poses a significant threat to reproductive function owing, in part, to hormonal disturbances caused by negative feedback between excess adiposity and the hypothalamic-pituitary-ovarian axis. Consequently, finding the most appropriate strategies to lose weight and improve ovulation in women with overweight or obesity is a clinically relevant matter that needs to be investigated. A comprehensive comparison of the independent and combined efficacy of lifestyle and/or pharmacological interventions on BMI, ovulation, and hormonal profile in women with overweight or obesity at risk of anovulatory infertility would facilitate improving fertility strategies in this population.

OBJECTIVE AND RATIONALE

This study aimed to evaluate the comparative efficacy of exercise, diet, and pharmacological interventions on BMI, ovulation, and hormonal profile in reproductive-aged women with overweight or obesity.

SEARCH METHODS

A systematic review was performed by searching PubMed, Scopus, Web of Science, PsycINFO, and Cochrane Library up to 14 December 2023, for randomized controlled trials assessing the effects of exercise, diet and/or pharmacological interventions (i.e. weight-lowering drugs or ovulation inducers) on BMI, ovulation, and/or hormonal profile in reproductive-aged women with overweight or obesity. We performed frequentist random-effect network meta-analyses and rated the certainty of the evidence. The primary outcomes were BMI and ovulation rate, and the secondary outcomes were serum reproductive hormone levels (gonadotrophins, androgens, or oestrogens). We performed sensitivity analyses, including the studies that only involved women with PCOS.

OUTCOMES

Among 1190 records screened, 148 full texts were assessed for eligibility resulting in 95 trials (9910 women), of which 53% presented a high or unclear risk of bias. The network meta-analyses revealed that, compared to control: diet combined with weight-lowering drugs (mean difference (MD) -2.61 kg/m2; 95% CI -3.04 to -2.19; τ2 = 0.22) and adding exercise (MD -2.35 kg/m2; 95% CI -2.81 to -1.89; τ2 = 0.22) led to the greatest decrease in BMI; exercise combined with diet and ovulation inducers (risk ratio (RR) 7.15; 95% CI 1.94-26.40; τ2 = 0.07) and exercise combined with diet and weight-lowering drugs (RR 4.80; 95% CI 1.67-13.84; τ2 = 0.07) produced the highest increase in ovulation rate; and exercise combined with diet and weight-lowering drugs was the most effective strategy in reducing testosterone levels (standardized mean difference (SMD) -2.91; 95% CI -4.07 to -1.74; τ2 = 2.25), the third most effective strategy in increasing sex hormone-binding globulin levels (SMD 2.37; 95% CI 0.99-3.76; τ2 = 2.48), and it was coupled with being ranked first in terms of free androgen index reduction (SMD -1.59; 95% CI -3.18 to 0.01; τ2 = 1.91). The surface under the cumulative ranking curve scores suggested that: diet combined with weight-lowering drugs is the strategy most likely (94%) to produce the highest BMI reduction; and exercise combined with diet and ovulation inducers is the strategy most likely (89%) to produce the highest ovulation rate improvement. The sensitivity analyses, which exclusively included studies involving women diagnosed with PCOS, were consistent with the results presented above.

WIDER IMPLICATIONS

Overall, the findings of this network meta-analysis indicate that the combination of exercise, diet, and pharmacological interventions is effective for weight loss, improving ovulation, and normalizing the androgen levels of women with overweight or obesity. Although higher quality studies are needed, these results support that the optimal treatment strategy for women with overweight or obesity wishing to conceive must consider exercise, diet, and pharmacological interventions during the shared decision-making process.

Endometrium development patterns and BMI groups among in vitro fertilization patients; prognostic aspects

Introduction

The impact of the obesity pandemic on female reproductive capability is a factor that needs to be investigated. In addition, the link between endometrial thickness and in vitro fertilization (IVF) outcomes is contentious.

Goal

Our goal was to analyze the association among endometrium development, hormone levels, embryo quality, clinical pregnancy, anamnestic parameters, and body mass index (BMI) in women receiving IVF treatment.

Patients and methods

537 participants undergoing IVF/ICSI cycles with successful oocyte retrieval were enrolled. Subjects were divided into four BMI based groups: underweight (UW; n=32), normal weight (NW; n=324), overweight (OW; n= 115), obesity (OB; n=66). Anthropometric and anamnestic parameters, characteristics of stimulation, endometrial thickness on the day of hCG injection, at puncture, at embryo transfer, FSH, LH, AMH, partner's age and the semen analysis indicators, embryo quality, clinical pregnancy, were recorded and analyzed. Support Vector Machine (SVM) was built to predict potential pregnancies based on medical data using 22 dimensions.

Results

In accordance with BMI categories, when examining pregnant/non-pregnant division, the average age of pregnant women was significantly lower in the UW (30.9 ± 4.48 vs. 35.3 ± 5.49 years, p=0.022), NW (34.2 ± 4.25 vs. 36.3 ± 4.84 years, p<0.001), and OW (33.8 ± 4.89 vs. 36.3 ± 5.31 years, p=0.009) groups. Considering FSH, LH, and AMH levels in each BMI category, a statistically significant difference was observed only in the NW category FSH was significantly lower (7.8 ± 2.99 vs. 8.6 ± 3.50 IU/L, p=0.032) and AMH (2.87 ± 2.40 vs. 2.28 ± 2.01 pmol/L, p=0.021) was higher in pregnant women. There were no further statistically significant differences observed between the pregnant and non-pregnant groups across any BMI categories, especially concerning endometrial development. Surprisingly, BMI and weight correlated negatively with FSH (r=-0.252, p<0.001; r=-0.206, p<0.001, respectively) and LH (r= -0.213, p<0.001; r= -0.195, p<0.001) in the whole population. SVM model average accuracy on predictions was 61.71%.

Discussion

A convincing correlation between endometrial thickness development and patients' BMI could not be substantiated. However, FSH and LH levels exhibited a surprising decreasing trend with increasing BMI, supporting the evolutionary selective role of nutritional status. Our SVM model outperforms previous models; however, to confidently predict the outcome of embryo transfer, further optimization is necessary.

Longitudinal changes in reproductive hormones through the menopause transition in the Avon Longitudinal Study of Parents and Children (ALSPAC)

We characterised changes in reproductive hormones-LH, FSH, SHBG and AMH-by chronological age and time around the menopause (reproductive age) in mid-life women and explored their associations with lifestyle and reproductive factors. We used data from 1608 women from a UK cohort who had repeat hormone measures and experienced a natural menopause. Multilevel models were used to assess: (i) changes in hormones (outcomes) by reproductive age and chronological age (these age variables being the key exposures) and (ii) associations of body mass index (BMI), smoking, alcohol intake, parity and age at menarche with changes in hormones by reproductive age. Both LH and FSH increased until ~ 5 and 7 years postmenopause, respectively, after which they declined, but not to premenopausal levels. SHBG decreased slightly until ~ 4 years postmenopause and increased thereafter. AMH decreased markedly before menopause and remained low subsequently. For all hormones, the best fitting models included both reproductive and chronological age. BMI, smoking and parity were associated with hormone changes; e.g., higher BMI was associated with slower increase in LH and FSH and decrease in AMH. Reproductive and chronological age contribute to changes in LH, FSH, SHBG and AMH across mid-life in women, and BMI, smoking and parity are associated with these hormone changes.

Adiposity and sex hormones across the menstrual cycle: the BioCycle Study

Objective

To investigate the influence of adiposity on patterns of sex hormones across the menstrual cycle among regularly menstruating women.

Subjects

The BioCycle Study followed 239 healthy women for 1–2 menstrual cycles, with up to 8 visits per cycle timed using fertility monitors.

Methods

Serum estradiol (E2), progesterone, luteinizing hormone (LH), follicle-stimulating hormone (FSH), and sex hormone binding globulin (SHBG) were measured at each visit. Adiposity was measured by anthropometry and by dual energy x-ray absorptiometry. Differences in hormonal patterns by adiposity measures were estimated using nonlinear mixed models, which allow for comparisons in overall mean levels, amplitude (i.e. lowest to highest level within each cycle), and shifts in timing of peaks while adjusting for age, race, energy intake, and physical activity.

Results

Compared to normal weight women (n=154), obese women (BMI≥30 kg/m², n=25) averaged lower levels of progesterone (−15%, P=0.003), LH (−17%, P=0.01), FSH (−23%, P=0.001) and higher free E2 (+22%, p=0.001) across the cycle. To lesser magnitudes, overweight women (BMI: 25–30, n=60) also exhibited differences in the same directions for mean levels of free E2, FSH, and LH. Obese women experienced greater changes in amplitude of LH (9%, p=0.002), and FSH (8%, p=0.004), but no differences were observed among overweight women. Higher central adiposity by top compared to bottom tertile of trunk-to-leg fat ratio by DXA was associated with lower total E2 (−14%, p=0.005) and FSH (−15%, p=0.001). Peaks in FSH and LH occurred later (~0.5 day) in the cycle among women with greater central adiposity.

Conclusion

Greater total and central adiposity were associated with changes in mean hormone levels. The greater amplitudes observed among obese women suggest compensatory mechanisms at work to maintain hormonal homeostasis. Central adiposity may be more important in influencing timing of hormonal peaks than total adiposity.

Endogenous Hormones and Ovarian Cancer: Epidemiology and Current Hypotheses

The effect of major epidemiologic risk factors for ovarian cancer has been reviewed in the light of several hormonal hypotheses, including the gonadotropin, androgens, progesterone, estrogens, insulin-like growth factor-I, and insulin hypotheses. The role of inclusion cyst formation and Mullerian epithelium differentiation in the pathology of the disease are also briefly outlined. Although based on limited data, the observed tendency in current evidence suggests possible etiologic roles for elevated androgens and estrogens and decreased progesterone in the pathogenesis of ovarian cancer. A direct effect of gonadotropins cannot be entirely ruled out, but it is plausible that their effect on ovarian cancer risk is mediated by stimulation of ovarian steroidogenesis. Insulin-like growth factor-I also emerges as a hormone that may be directly involved in the pathogenesis of the disease, but thus far only one prospective study has examined this association. Hyperinsulinemia is an unlikely risk factor for ovarian cancer. The observed tendency for an increased risk with androgens from ovarian origin (in premenopausal women), the lack of association with adrenal androgens, and the relatively weak associations observed with obesity, hormonal replacement therapy use, and endogenous hormones after menopause suggest that ovarian synthesis of sex steroids rather than their circulating levels may be etiologically important. More data from prospective studies will be crucial to improve our understanding of the etiologic role of endogenous hormones in the pathogenesis of ovarian cancer. Such data will ultimately provide opportunities for research targeted; at early detection and preventive interventions.

Urinary reproductive hormone level differences between African American and Caucasian women of reproductive age

OBJECTIVE

To compare urinary levels of reproductive hormones in African American and Caucasian women.

DESIGN

Cross-sectional study.

SETTING

Ten United States Air Force (USAF) bases.

PATIENT(S)

African American (n = 33) and Caucasian (n = 65) women of reproductive age from a larger study of USAF women (n = 170).

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

Urinary endocrine end points: follicular luteinizing hormone (LH), preovulatory LH, level of LH surge peak, early follicular follicle stimulating hormone (FSH), follicular LH:FSH ratio, midluteal FSH, FSH rise before menses, early follicular estrone 3-glucuronide (E(1)3G), midfollicular E(1)3G, periovulatory E(1)3G peak, midluteal E(1)3G, early follicular pregnanediol 3-glucuronide (Pd3G), follicular Pd3G, rate of periovulatory Pd3G increase, E(1)3G:Pd3G on the day of luteal transition, slope of E(1)3G:Pd3G, and midluteal Pd3G.

RESULT(S)

Relative to Caucasians, African American women had significantly lower follicular phase LH:FSH ratios (mean +/- SD: 0.7 +/- 0.4 vs. 1.0 +/- 0.6), lower follicular phase Pd3G levels (1.0 +/- 0.5 vs. 1.2 +/- 0.8 microg/mg creatinine), and lower rates of periovulatory Pd3G increase (0.5 +/- 0.7 vs. 1.0 +/- 1.2 microg/mg creatinine).

CONCLUSION(S)

Findings of this analysis should be considered preliminary evidence of racial differences in hormone levels. Future studies are needed to determine whether these differences have clinical significance.

Body mass index in relation to ovarian cancer: a multi-centre nested case-control study

The incidence of ovarian cancer is up to 10 times higher in Western countries than in rural Asia and Africa. One common consequence of a Western lifestyle is the development of excessive body weight and obesity. A multi-centre prospective study was conducted to investigate the association between body mass index (BMI) and ovarian cancer risk. A case-control study was nested within 3 prospective cohorts in New York (USA), Umeå (Sweden) and Milan (Italy). Information on anthropometry, demographic characteristics, medical history and lifestyle was obtained at the time of subjects' recruitment in each cohort. Women diagnosed with primary, invasive epithelial ovarian cancer from the 3 cohorts (n = 122) diagnosed 12 months or later after recruitment into the respective cohort served as case subjects. For each case subject, 2 control subjects that matched the case subject on cohort, menopausal status, age and date of recruitment were randomly identified. Data were analyzed by conditional logistic regression. There was an inverse association between BMI and ovarian cancer risk. For increasing quartiles of BMI above the lowest, the ORs were 0.62 (0.32-1.21), 0.59 (0.30-1.17) and 0.46 (0.23-0.92), p = 0.03. Analyses limited to women diagnosed 3 or more years after recruitment into the cohorts did not alter these findings. When obese women (BMI > 30) were compared to lean women (BMI < or = 23), the inverse association became stronger, with an OR of 0.38 (0.17-0.85), p < 0.02. There was some evidence of direct association of ovarian cancer with height, which was limited to cancers diagnosed before age 55. Our data suggest that increasing body weight may confer a protection against ovarian cancer.

Polycystic ovary syndrome. A diagnostic challenge

Polycystic ovary syndrome remains a diagnostic challenge because there is no single defining test. The clinical presentation must dictate the extent of the work-up. The typical PCOS patient has a history of irregular menses and appears hirsute. Demonstration of ovulatory dysfunction and hyperandrogenism can also be made by appropriate hormonal measurements. An ultrasound showing multiple small ovarian follicles can support a diagnosis of PCOS in the patient for whom the clinical diagnosis has been made. Other causes of hyperandrogenism and ovulatory dysfunction should be excluded.