Association Between Body Mass Index and Female Infertility in the United States: Data from National Health and Nutrition Examination Survey 2013–2018

Abstract

Purpose This study aimed to investigate the effects of body mass index (BMI) on infertility in women of childbearing age. Patients and Methods We performed a cross-sectional study using data from 3624 participants from the National Health and Nutrition Examination Survey (NHANES). We used BMI and fertility status in the survey as independent and dependent variables, respectively. We evaluated their relationship and used smoothed curve fitting and multivariate logistic regression analysis as well as a generalized additive model (GAM) to determine the effect of BMI. Results Logistic regression model analysis linked BMI and infertility after adjusting for potential confounders OR 1.03, 95%Cl: 1.02–1.05). There was a non-linear relationship between BMI and infertility, with each unit increase in BMI reducing the risk of infertility by 33% when BMI was <19.5 kg/m 2 . In contrast, when BMI ≥19.5 kg/m 2 , each unit increase in BMI predicted a 3% increase in the risk of infertility. Conclusion The relationship between infertility and BMI presented a U-shaped curve. Therefore, a BMI that lay at the extremes of the spectrum tended to predict infertility. We believe that this study will support the maintenance of suitable BMI levels in women preparing for pregnancy.

Gynecological co-morbidity, chronic illnesses and infectious diseases among black African women with primary or secondary infertility: should we be worried about hepatitis?

“…For example Zhu et al predicted that the relationship between infertility and BMI presented a U-shaped curve and that underweight and obese BMI tended to predict infertility. 32 In this study, the proportion of women that were obese (52.2%) or overweight (33.9%) was higher than the respective 46.4% or 39.4% reported from a study in Algeria. 33 However, there was no significant difference of the effect of BMI on primary and secondary infertility, though further studies on factors not considered in this study, such as insulin-sensitizing adipokines and abundance of adipose tissues 34 may demonstrate potential effects of BMI on the two types of infertility.…”

Obesity inflicted reproductive complications and infertility in men

“…Infertility may result from an obesity-induced imbalance in the male and female reproductive system 9,10 . Obese females suffer from irregular and excessive menstruation 11 , polycystic ovary syndrome (PCOS) 12 , increase in endometrial thickness 13 , uterine fibroids and endometriosis 14,15 , pre-eclampsia and eclampsia (complications of pregnancy) 16 infertility 17 and miscarriage 18 .…”

Omega-3 fatty acids dietary intake for oocyte quality in women undergoing assisted reproductive techniques: A systematic review

“…To maximise the success rate of the ART cycle, the general health and lifestyle of the couple are evaluated prior to treatment together with physical and BMI measures. Despite the close relation observed between obesity and poor reproductive outcome in the last 25 years, the mechanisms are still ambiguous [47]. Moreover, multiple studies highlighted the association between ovulation abnormalities and higher intakes of food categories such as dairy [1], animal proteins, carbohydrates, alcoholic beverages and caffeine [38].…”