Body Fat Distribution and Female Infertility: a Cross-Sectional Analysis Among US Women

Associations of nutritional status and dietary habits with the development of female infertility. A case-control study

Introduction

Female infertility is a multifactorial condition influenced by lifestyle and dietary factors. Understanding the relationship between nutritional status, dietary habits, and infertility could provide insights for targeted interventions.

Methods

A case-control study was conducted in health centers and hospitals in Alicante, Spain. The study included 60 infertile and 30 fertile women aged 18-40, selected through consecutive sampling. Data on body composition and dietary intake were collected and analyzed.

Results

Infertile women exhibited significantly lower muscle mass (p = 0.005) and larger hip circumference (p = 0.034) compared to fertile women. Additionally, a significant association was found between high red meat consumption and an increased risk of female infertility (p = 0.011).

Discussion

These results suggest that body composition and dietary habits, particularly muscle mass and red meat intake, play a key role in female fertility. Interventions aimed at improving muscle mass, reducing localized body fat, and limiting red meat consumption may enhance fertility outcomes. Further longitudinal research is needed to confirm these findings across diverse populations.

Association between visceral adipose tissue area and infertility: a cross-sectional analysis

RESEARCH QUESTION

Is intra-abdominal fat obesity associated with infertility?

DESIGN

This study analysed data from the 2013-2018 National Health and Nutrition Examination Survey, with a total of 3013 women enrolled. The participants were divided into two groups: infertility and non-infertility. Differences between the two groups were analysed using a weighted Student's t-test or Mann-Whitney U-test for continuous variables, or a weighted chi-squared test for categorical data. Visceral adipose tissue area (VATA) was assessed by dual-energy X-ray absorptiometry. The independent association between infertility and log VATA was assessed by weighted multivariate logistic regression models. Subgroup analyses were performed to assess the strength of the results. Interaction tests were used to examine whether covariates interacted with log VATA to influence infertility.

RESULTS

Log VATA was significantly higher in the infertility group compared with the non-infertility group (P < 0.001). After adjustment for potential confounders, the results of multivariate logistic regression analysis revealed that an increase in log VATA was associated with increased prevalence of female infertility (OR = 2.453, 95% CI 1.278-4.792). Subgroup analyses showed this association in individuals aged <35 years (P = 0.002), Mexican-Americans (P = 0.033), non-hypertensive individuals (P = 0.013) and non-diabetic individuals (P = 0.003).

CONCLUSIONS

An enlarged VATA is associated with increased risk of infertility. The direct effect of VATA on female infertility needs to be clarified further to provide a basis for future prevention and treatment of female infertility.

The association between fat distribution and α1-acid glycoprotein levels among adult females in the United States

BACKGROUND

Visceral fat accumulation and obesity-induced chronic inflammation have been proposed as early markers for multiple disease states, especially in women. Nevertheless, the potential impact of fat distribution on α1-acid glycoprotein(AGP), a marker of inflammation, remains unclear. This research was conducted to investigate the relationships among obesity, fat distribution, and AGP levels.

METHODS

A cross-sectional observational study was performed using blood samples from adult females recruited through the National Health and Nutrition Examination Survey from 2015 to 2018. Serum levels of AGP were measured using the Tina-quant α-1-Acid Glycoprotein Gen.2 assay. Based on the fat distribution data obtained from dual-energy X-ray absorptiometry assessments, body mass index (BMI), total percent fat (TPF), android percent fat (APF), gynoid percent fat (GPF), android fat/gynoid fat ratio (AGR), visceral percent fat (VPF), subcutaneous percent fat (SPF), visceral fat/subcutaneous fat ratio (VSR) were used as dependent variables. To investigate the link between fat distribution and AGP, multivariate linear regression analysis was utilized. Furthermore, a sensitivity analysis was also performed.

RESULTS

The present study included 2,295 participants. After adjusting for covariates, BMI, TPF, APF, GPF, VPF, and SPF were found to be positively correlated with AGP levels (BMI: β = 23.65 95%CI:20.90-26.40; TPF: β = 25.91 95%CI:23.02-28.80; APF: β = 25.21 95%CI:22.49-27.93; GPF: β = 19.65 95%CI:16.96-22.34; VPF: β = 12.49 95%CI:9.08-15.90; SPF: β = 5.69, 95%CI:2.89-8.49; AGR: β = 21.14 95%CI:18.16-24.12; VSR: β = 9.35 95%CI:6.11-12.59, all P < 0.0001). All the above indicators exhibited a positive dose-response relationship with AGP. In terms of fat distribution, both AGR and VSR showed positive associations with AGP (P for trend < 0.0001). In particular, when compared to individuals in tertile 1 of AGR, participants in tertiles 2 and 3 had 13.42 mg/dL (95% CI 10.66-16.18) and 21.14 mg/dL (95% CI 18.16-24.12) higher AGP levels, respectively. Participants in the highest tertile of VSR were more likely to exhibit a 9.35 mg/dL increase in AGP compared to those in the lowest tertile (95% CI 6.11-12.59).

CONCLUSIONS

Overall, this study revealed a positive dose-dependent relationship between fat proportion/distribution and AGP levels in women. These findings suggest that physicians can associate abnormal serum AGP and obesity with allow timely interventions.

Association between Waist-Hip Ratio and Female Infertility in the United States: Data from National Health and Nutrition Examination Survey 2017-2020

INTRODUCTION

Obesity has previously been correlated with an elevated risk of reproductive system diseases in women. The waist-hip ratio (WHR) has been shown to be correlated with visceral fat, making it one of the most commonly used indicators of abdominal obesity. However, little is known about the relationship between WHR and infertility. Therefore, the aim of this study was to evaluate the effect of the WHR on infertility in women of childbearing age.

METHODS

The study used cross-sectional data from women aged 20-45 who participated in the National Health and Nutrition Examination Survey (NHANES), which was conducted between 2017 and 2020. We collected details of their waist circumference, hip circumference, fertility status, and several other essential variables. We used multivariate logistic regression analysis and subgroup analyses to assess the association between WHR and infertility.

RESULTS

There were 976 participants, with 12.0% (117/976) who experienced infertility. After adjusting for potential confounding factors, our multivariate logistic regression analysis revealed that every 0.1 unit increase in WHR resulted in a more than 35% higher risk of infertility (odds ratio [OR; 95% confidence interval [CI]: 1.35 [1.01∼1.81], p = 0.043). Compared to the group with WHR <0.85, the risk of infertility increased in the group with WHR ≥0.85, with an adjusted OR of 1.74 (95% CI: 1.06∼2.85). When WHR was treated as a continuous variable, it was observed that each 0.1 unit increase in WHR was associated with a relatively high risk in the secondary infertility population after adjusting all covariates, with an OR of 1.66 (95% CI: 1.14∼2.40, p = 0.01). When WHR was analyzed as a categorical variable, the group with WHR ≥0.85 exhibited a significantly higher risk of secondary infertility than the group with WHR <0.85, with the OR of 2.75 (95% CI: 1.35-5.59, p = 0.01) after adjusting for all covariates. Furthermore, the interaction analysis indicated that there was a significant interaction between age status on WHR and the risk of infertility.

CONCLUSION

WHR showed a positive correlation with the risk of infertility. This study highlights the importance of effectively managing abdominal fat and promoting the maintenance of optimal WHR levels to mitigate the progression of infertility, particularly for younger women.

The association of Life's Simple 7 and infertility among U.S. women

Background

The Life's Simple 7 (LS7) metric is a comprehensive measure of cardiovascular health (CVH) that encompasses seven distinct risk factors and behaviors associated with cardiovascular disease (CVD). Some studies have shown an association between infertility and CVD. The present study aimed to explore the potential association between the LS7 factors and infertility.

Methods

A cross-sectional study was conducted on a sample of 3537 women aged 18-44 years from the National Health and Nutrition Examination Survey (NHANES) spanning the years 2013-2018. The LS7 metrics encompassed various factors including physical activity, smoking habits, body mass index, blood pressure levels, dietary patterns, blood glucose levels, and total cholesterol levels. We computed a 14-point LS7 score based on participants' baseline data, classifying them as "inadequate" (3-6), "average" (7-10), or "ideal" (11-14). Infertility is defined as an affirmative answer to either of two questions on the NHANES questionnaire: "Have you tried to conceive for at least one year without success?" and "Have you sought medical help for your inability to conceive?" Logistic regression was utilized to estimate odds ratios (O.R.s) and 95% confidence intervals (C.I.s).

Results

In total, 17.66% of participants were classified as individuals who reported experiencing infertility. In the continuous analysis, each one-unit increase in LS7 score was associated with a significantly decreased odds of infertility (OR=0.88 [0.77-0.89]). Analyzing the categorical representation of LS7 score, compared to individuals with poor scores, those with ideal scores exhibited a substantial 58% reduction in the odds of infertility (OR=0.42 [0.26-0.69]). Additionally, the observed interaction suggested that the influence of age on the relationship between LS7 and infertility is not consistent across different age groups (P for interaction < 0.001). Among individuals aged 35 or younger, each unit increase in LS7 score was associated with a substantial 18% (OR=0.82 [0.76-0.89]) decrease in the odds of infertility. However, in the older age group (>35), the association was attenuated and non-significant.

Conclusions

Our research suggests a significant inverse association between LS7 scores and infertility. Age demonstrated a varying impact on this relationship, with a more pronounced impact observed among individuals aged 35 or younger.