Impact of obesity on male and female reproductive outcomes

Association between indicators of visceral lipid accumulation and infertility: a cross-sectional study based on U.S. women

BACKGROUND

Evidence on the association between visceral lipid accumulation and infertility remains limited and controversial. Therefore, the current investigation is the first investigation to unveil this correlation by utilizing novel indicators of visceral lipid accumulation.

METHODS

The present study utilized the NHANES 2013-2020 dataset. Researchers utilized multiple logistic regression, smoothed curve fitting, and subgroup analysis to investigate the associations of waist circumference (WC), metabolic score for visceral fat (METS-VF), lipid accumulation product (LAP), visceral adiposity index (VAI) with infertility. Additionally, the eXtreme Gradient Boosting (XGBoost) algorithm model was utilized to evaluate the relative importance of the factors.

RESULTS

After adjusting for potential factors that could influence the results, researchers discovered that all these four indicators of visceral lipid accumulation exhibited strong positive correlations with the probability of infertility. The subgroup analysis demonstrated that the correlations remained consistent in the majority of subgroups (P for interaction > 0.05). The results of XGBoost algorithm model indicate that METS-VF is the most meaningful factor in infertility. The ROC curve research revealed that while METS-VF had the greatest AUC values, there was no variation in the AUC value of different markers of visceral fat accumulation (P > 0.05).

CONCLUSIONS

The present investigation discovered that increased WC, METS-VF, LAP, and VAI were associated with a heightened prevalence of infertility.

Prevalence of overweight and its associated factors among Malaysian adults: Findings from a nationally representative survey

The World Health Organization has reported that the prevalence of overweight is a growing problem in many countries, including middle- and lower-income countries like Malaysia. This study aimed to determine the prevalence of overweight and its associated factors among Malaysian adults. A total of 9782 Malaysian adults aged 18 and above were included in this study, representing states and federal territories from the National Health and Morbidity Survey 2019. Sociodemographic data (sex, locality, age, marital status, ethnicity, educational level, income level, and health literacy), non-communicable disease status (hypertension, diabetes, and hypercholesterolemia), and lifestyle behaviours (physical activity level, smoking status, and also fruit and vegetable consumption) were collected and analysed to identify factors associated with overweight. The study found that the prevalence of overweight among Malaysian adults was 50.1%. Multivariate analyses showed that several factors, including female gender [aOR (95% CI) = 1.33 (1.11, 1.58); p = .002], ages 30-59 years [aOR (95% CI) = 1.61 (1.31, 1.97); p < .001], being Malay [aOR (95% CI) = 1.68 (1.36, 2.07); p < .001], Indian [aOR (95% CI) = 2.59 (1.80, 3.74); p < .001] or other Bumiputera [aOR (95% CI) = 1.82 (1.38, 2.39); p < .001], being married [aOR (95% CI) = 1.23 (1.00, 1.50); p = .046], and having adequate health literacy [aOR (95% CI) = 1.19 (1.01, 1.39); p = .033], were significantly associated with an increased risk of overweight. Additionally, overweight individuals had a significantly higher risk of non-communicable diseases such as diabetes [aOR (95% CI) = 1.47 (1.23, 1.75); p < .001] and hypertension [aOR (95% CI) = 2.60 (2.20, 3.07); p < .001]. The study suggests that intervention programs should be implemented in an equitable and cost-effective manner to target these high-risk populations and address the burden of overweight in Malaysia.

Patient perceptions of body mass index restrictions limiting fertility care for women with high body mass index

RESEARCH QUESTION

What is the patient experience of women with high body mass index (BMI) with BMI restrictions that limit fertility care?

DESIGN

Qualitative study using in-depth, semi-structured interview methodology. Interview transcripts were analysed for iterative themes in accordance with principles of grounded theory.

RESULTS

Forty women with a BMI of 35 kg/m2 or higher with scheduled or completed appointment at the Reproductive Endocrinology and Infertility (REI) clinic completed an interview. Most participants experienced BMI restrictions as unjust. Many perceived that BMI restrictions on fertility care may be medically justified and were in support of weight loss discussions to improve chances of pregnancy; however, several argued that they should have autonomy to commence treatment following an individualized risk assessment. Participants offered recommendations to improve discussion of BMI restrictions and weight loss, including framing the conversation as supportive of their reproductive goals and offering proactive referral to weight loss support to prevent the perception that BMI is a categorical exclusion to future fertility care.

CONCLUSIONS

Participant experiences highlight a need for enhanced strategies for communicating BMI restrictions and weight loss recommendations in ways that are perceived to be supportive of patients' fertility goals without further contributing to weight bias and stigma experienced in medical settings. Opportunities for training to mitigate experiences of weight stigma may be beneficial for clinical and non-clinical staff. Evaluation of BMI policies should be undertaken within the context of clinic policies that permit or prohibit fertility care for other high-risk groups.

Effect of ovulation before or after intrauterine insemination on pregnancy outcome in patients with unexplained infertility or polycystic ovarian syndrome

OBJECTIVE

To investigate the relationship between ovulation and pregnancy outcomes in patients undergoing intrauterine insemination (IUI).

METHODS

The clinical data from 784 patients, diagnosed with polycystic ovarian syndrome (PCOS) or unexplained infertility, underwent 1624 IUI cycles were analyzed retrospectively. Ovulation was observed by transvaginal ultrasonography on the day of IUI. The clinical pregnancy rate (CPR), abortion rate (AR), and live birth rate (LBR) were analyzed.

RESULTS

The study included 1031 pre-ovulation IUI cycles (63.49%) and 593 post-ovulation IUI cycles (36.51%). The CPR was 13.05%, the AR was 15.57%, and the LBR was 11.02%. Ovulation before or after IUI affected the CPR (11.06% VS 16.53%, p = .002) and LBR (9.41% VS 13.83%, p = .006) per cycle, but did not affect the AR (14.91% VS 16.33%, p = .149). The sex ratio of children was not related to ovulation (p = .948). After adjusting for baseline characteristics and logistic regression, the CPR (OR = 1.931, 95% CI 1.062-1.931, p = .019) and LBR (OR = 1.389, 95% CI 1.007-1.916, p = .045) of post-ovulation insemination were higher than those of pre-ovulation insemination significantly.

CONCLUSION

Pregnancy outcomes were affected by ovulation on the day of IUI in patients with unexplained infertility or PCOS. Post-ovulation insemination may improve the CPR of IUI.

Obesity: A Doorway to a Molecular Path Leading to Infertility

The dramatic rise in obesity has recently made it a global health issue. About 1.9 billion were overweight, and 650 million global populations were obese in 2016. Obese women suffer longer conception time, lowered fertility rates, and greater rates of miscarriage. Obesity alters hormones such as adiponectin and leptin, affecting all levels within the hypothalamic-pituitary-gonadal axis. Advanced glycation end products (AGEs) and monocyte chemotactic protein-1 (MCP-1) are inflammatory cytokines that may play an important role in the pathophysiology of ovarian dysfunction in obesity. In obese males, there are altered sperm parameters, reduced testosterone, increased estradiol, hypogonadism, and epigenetic modifications transmitted to offspring. The focus of this article is on the possible adverse effects on reproductive health resulting from obesity and sheds light on different molecular pathways linking obesity with infertility in both female and male subjects. Electronic databases such as Google Scholar, Embase, Science Direct, PubMed, and Google Search Engine were utilized to find obesity and infertility-related papers. The search strategy is detailed in the method section. Even though multiple research work has shown that obesity impacts fertility in both male and female negatively, it is significant to perform extensive research on the molecular mechanisms that link obesity to infertility. This is to find therapeutics that may be developed aiming at these mechanisms to manage and prevent the negative effects of obesity on the reproductive system.

Maternal Exposure to Per- and Polyfluoroalkyl Substances (PFAS) and Male Reproductive Function in Young Adulthood: Combined Exposure to Seven PFAS

BACKGROUND

Concerns remain about the human reproductive toxicity of the widespread per- and polyfluoroalkyl substances (PFAS) during early stages of development.

OBJECTIVES

We examined associations between maternal plasma PFAS levels during early pregnancy and male offspring reproductive function in adulthood.

METHODS

The study included 864 young men (age range:18.9-21.2 y) from the Fetal Programming of Semen Quality (FEPOS) cohort established between 2017 and 2019. Plasma samples from their mothers, primarily from the first trimester, were retrieved from the Danish National Biobank and levels of 15 PFAS were measured. Seven PFAS had detectable levels above the limit of detection in >80% of the samples and were included in analyses. Semen quality, testicular volume, and levels of reproductive hormones and PFAS were assessed in the young men. We used weighted quantile sum (WQS) regression to estimate the associations between combined exposure to maternal PFAS and reproductive function, and negative binomial regression to estimate the associations of single substances, while adjusting for a range of a priori-defined fetal and postnatal risk factors.

RESULTS

By a 1-unit increase in the WQS index, combined maternal PFAS exposure was associated with lower sperm concentration (-8%; 95% CI: -16%, -1%), total sperm count (-10%; 95% CI: -17%, -2%), and a higher proportion of nonprogressive and immotile sperm (5%; 95% CI: 1%, 8%) in the young men. Different PFAS contributed to the associations with varying strengths; however, perfluoroheptanoic acid was identified as the main contributor in the analyses of all three outcomes despite the low concentration. We saw no clear association between exposure to maternal PFAS and testicular volume or reproductive hormones.

DISCUSSION

In a sample of young men from the general Danish population, we observed consistent inverse associations between exposure to maternal PFAS and semen quality. The study needs to be replicated in other populations, taking combined exposure, as well as emerging short-chain PFAS, into consideration. https://doi.org/10.1289/EHP10285.

Inflammatory and metabolic markers in relation to outcome of in vitro fertilization in a cohort of predominantly overweight and obese women

For overweight and obese women undergoing in vitro fertilization (IVF) the pregnancy and live birth rates are compromised while the underlying mechanisms and predictors are unclear. The aim was to explore the association between adipose tissue-related inflammatory and metabolic markers and the pregnancy and live birth outcome of IVF in a cohort of predominantly overweight and obese women. Serum samples, fulfilling standardizing criteria, were identified from 195 women having participated in either the control (n = 131) or intervention (n = 64) group of a randomized controlled trial (RCT), seeking to evaluate the effect of a weight reduction intervention on IVF outcome in obese women. Serum high-sensitivity C-reactive protein (hsCRP) and the adipokines leptin and adipocyte fatty acid-binding protein (AFABP) were analyzed for the whole cohort (n = 195) in samples collected shortly before IVF [at randomization (control group), after intervention (intervention group)]. Information on age, anthropometry [BMI, waist circumference, waist-to-height ratio (WHtR)], pregnancy and live birth rates after IVF, as well as the spontaneous pregnancy rate, was extracted or calculated from collected data. The women of the original intervention group were also characterized at randomization regarding all variables. Eight women [n = 3 original control group (2.3%), n = 5 original intervention group (7.8%)] conceived spontaneously before starting IVF. BMI category proportions in the cohort undergoing IVF (n = 187) were 1.6/20.1/78.3% (normal weight/overweight/obese). The pregnancy and live birth rates after IVF for the cohort were 35.8% (n = 67) and 24.6% (n = 46), respectively. Multivariable logistic regression revealed that none of the variables (age, hsCRP, leptin, AFABP, BMI, waist circumference, WHtR) were predictive factors of pregnancy or live birth after IVF. Women of the original intervention group displayed reductions in hsCRP, leptin, and anthropometric variables after intervention while AFABP was unchanged. In this cohort of predominantly overweight and obese women undergoing IVF, neither low-grade inflammation, in terms of hsCRP, other circulating inflammatory and metabolic markers released from adipose tissue (leptin, AFABP), nor anthropometric measures of adiposity or adipose tissue distribution (BMI, waist, WHtR) were identified as predictive factors of pregnancy or live birth rate.Trial registration: ClinicalTrials.gov number, NCT01566929. Trial registration date 30-03-2012, retrospectively registered.

Impairment of endometrial decidual reaction in early pregnant mice fed with high fat diet

OBJECTIVE

To investigate the effect of obesity induced by high fat diet on decidual reaction of endometrium in mice, and the effect of high fat treatment on decidual reaction of endometrial stromal cells.

METHODS

Twelve 4-week-old healthy C57BL/6J female mice were randomly divided into high fat diet group and control group with 6 mice in each group. They were fed with high fat diet (22 kJ/g) or normal diet (16 kJ/g) for 12 weeks, respectively. The body weight of mice was measured every week. After feeding for 12 weeks, the body length and width of mice were measured, and the levels of fasting serum triglyceride and total cholesterol were determined. Then the mice were mated with healthy C57BL/6J male mice, and the uterine tissues were collected on the seventh day of pregnancy. The decidual cells and collagen fibers in mouse endometrium was observed by HE staining and Masson staining respectively. The expression of decidual reaction related proteins in mouse endometrium were detected by immunohistochemistry and Western blotting. Mouse endometrial stromal cells (mESCs) were isolated and treated with the oleic acid and palmitic acid in vitro, and the decidual reaction was induced with estradiol and progesterone. The accumulation of lipid droplets in mESCs was observed by oil red O and Bodipy staining. The cytoskeleton of mESCs was observed by phalloidin staining. The levels of decidual reaction related genes and proteins were detected by real-time fluorescence quantitative PCR and Western blotting.

RESULTS

After feeding for 12 weeks, the body weight of mice in the high fat group was significantly higher than that in the control group ( P<0.01), and there was no significant difference in body length between two groups ( P>0.05), but the body width of mice in the high fat group was significantly larger than that in the control group ( P<0.01), and the levels of serum triglyceride and total cholesterol were significantly higher than those in the control group (Both P<0.05). The number of embryo implantation in the high fat group was significantly less than that in the control group ( P<0.01). The differentiation of mESCs to decidual cells in high fat group was slow and abnormal. The expression levels of decidual reaction markers bone morphogenetic protein (BMP)2 and homeobox A10 (HOXA10) were lower than those in the control group, and there was significant difference in the expression level of HOXA10 ( P<0.01). The results of oil red O and Bodipy staining in mESCs showed that after high fat treatment, the accumulation of lipid droplets increased significantly, phalloidin staining showed abnormal cytoskeleton morphology. The expression levels of decidual reaction related genes dtprp, HOXA10 and proteins BMP2, HOXA10 and cyclooxygenase (COX)2 were significantly lower than those in the control group ( P<0.05).

CONCLUSION

Obesity induced by high fat diet and high fat treatment can impair the decidual reaction of endometrium and endometrial stromal cells in mice.

Clinical impact of estradiol/testosterone ratio in patients with acute ischemic stroke

BACKGROUND

Sex hormones may be associated with a higher incidence of ischemic stroke or stroke-related events. In observational studies, lower testosterone concentrations are associated with infirmity, vascular disease, and adverse cardiovascular risk factors. Currently, female sexual hormones are considered neuroprotective agents. The purpose of this study was to assess the role of sex hormones and the ratio of estradiol/testosterone (E/T) in patients with acute ischemic stroke (AIS).

METHODS

Between January 2011 and December 2016, 146 male patients with AIS and 152 age- and sex-matched control subjects were included in this study. Sex hormones, including estradiol, progesterone, and testosterone, were evaluated in the AIS patient and control groups. We analyzed the clinical and physiological levels of sex hormones and hormone ratios in these patients.

RESULTS

The E/T ratio was significantly elevated among patients in the stroke group compared to those in the control group (P = 0.001). Categorization of data into tertiles revealed that patients with the highest E/T ratio were more likely to have AIS [odds ratio (OR) 3.084; 95% Confidence interval (CI): 1.616-5.886; P < 0.001) compared with those in the first tertile. The E/T ratio was also an independent unfavorable outcome predictor with an adjusted OR of 1.167 (95% CI: 1.053-1.294; P = 0.003).

CONCLUSIONS

These findings support the hypothesis that increased estradiol and reduced testosterone levels are associated with AIS in men.

Female obesity increases the risk of miscarriage of euploid embryos

OBJECTIVE

To determine whether female body mass index (BMI) is associated with an increased risk of miscarriage after euploid embryo transfer.

DESIGN

A retrospective, observational, multicenter cohort study.

SETTING

University-affiliated in vitro fertilization center.

PATIENT(S)

In this study, 3,480 cycles of in vitro fertilization with preimplantation genetic testing for aneuploidy (PGT-A) in the blastocyst stage and euploid embryo transfer were divided into four groups according to patient BMI.

INTERVENTION(S)

In vitro fertilization with PGT-A.

MAIN OUTCOME MEASURE(S)

The primary outcome was the miscarriage rate, which included both biochemical and clinical miscarriages. Secondary outcomes were implantation, pregnancy, clinical pregnancy, and live birth rates.

RESULT(S)

Cycles were divided into four groups according to BMI (kg/m²): underweight (<18.5; n = 155), normal weight (18.5-24.9; n = 2,549), overweight (25-29.9; n = 591), and obese (≥30; n = 185). The number of PGT-A cycles per patient was similar in the four groups. Fertilization rate, day of embryo biopsy, technique of chromosomal analysis, number of euploid embryos, number of transferred embryos, and method of endometrial preparation for embryo transfer were similar in the four BMI groups. Miscarriage rates were significantly higher in women with obesity compared to women with normal weight, mainly due to a significant increase in the clinical miscarriage rates. Live birth rates also were lower in women with obesity. Obesity in women and day 6 trophectoderm biopsy were found to influence the reduced live birth rate.

CONCLUSION(S)

Women with obesity experience a higher rate of miscarriage after euploid embryo transfer than women with a normal weight, suggesting that other mechanisms than aneuploidy are responsible for this outcome.

Effects of short-term exposure to high-fat diet on histology of male and female gonads in rats

Obesity, which reaches an epidemic, is characterized by alterations in metabolic and hormonal profiles. Moreover, uncontrolled obesity may lead to development of diabetes type 2, which accounts for about 90% of all diabetic cases. In obesity, besides changes in metabolism, numerous co-morbidities are reported, e.g. disruptions of reproductive functions. Additionally, sex differences in development of this disease occur. We hypothesized that short-term exposure to high-fat diet (HFD; containing 50% of total energy from fat) would alter histology of testes and ovaries, and thus contribute to reproductive disruptions in male and female rats. Adult rats were fed ad libitum with HFD for 6-7 weeks and its effects on histology of testes and ovaries (n = 4/sex and treatment group) were studied using hematoxylin-eosin staining followed by microscopic analysis and compared to control (laboratory chow fed) group. We have found that in male rats fed with HFD there were: 1) decrease in diameter of seminiferous tubules due to smaller luminar diameter, and no change in epithelium height; 2) decrease in number of Sertoli cells; 3) no changes in number of spermatogonia and in percentage of semen in seminiferous tubules. In female rats exposed to HFD we have seen: 1) decrease in diameters of corpora lutea; 2) decrease in diameter of ovarian follicles types 7 and 8, but no changes in their number; 3) no changes in number of early primary follicles, primary follicles, and secondary follicles. We concluded that relatively short-term exposure to HFD in rats leads to changes in histology of both testes and ovaries, thus affecting reproductive functions.

Effect of BMI on blood value of patients on HCG day with IUI treatment

BACKGROUND

This study aims to analyze the effect of the body mass index (BMI) on E₂, P and LH values in females who received intrauterine insemination (IUI) treatment on human chorionic gonadotropin (HCG) day.

METHODS

A total of 2319 cycles of IUI-assisted pregnancy treatment were selected in our hospital. Based on the BMI, female infertility patients are divided into three groups: normal weight group, overweight and obese group.

RESULTS

For patients with natural cycles and ≤ 35 years old, there were 440, 178 and 197 cases in the three groups, respectively. For patients with natural cycles and > 35 years old, there were 90, 83 and 81 cycles in the three groups, respectively. For patients with induced ovulation cycle and ≤ 35 years old, there were 425, 203 and 516 cases in the three groups, respectively. For patients with induced ovulation cycle and > 35 years old, there were 26, 26 and 54 cases in the three groups, respectively.

CONCLUSION

When a patient is ≤35 years old, the BMI affects the E₂, LH and P values on the day of artificial insemination. However, the BMI is negatively correlated with E₂, LH and P in IUI on HCG day. After controlling for age and assisted pregnancy, the correlation analysis revealed that the BMI is negatively correlated with hormone E₂ and LH. The higher the BMI was, the lower the levels of hormones E₂, LH and P became. However, in the present study, the BMI did not significantly improve the clinical pregnancy rate of patients who received IUI.