Effects of Paternal Obesity on Fetal Development and Pregnancy Complications: A Prospective Clinical Cohort Study

Paternal peri-conceptional physical activity and the risk of congenital heart disease in offspring: A case-control study

BACKGROUND

Genetic and environmental factors have been shown to contribute to the development of congenital heart disease (CHD). To date, the focus of scientific articles has primarily centered on genetics and maternal environmental factors, with comparatively less attention given to paternal risk factors.

OBJECTIVES

This study aims to investigate the potential association between paternal pre-conceptional physical activity levels (PA), along with paternal peri-conceptional smoking and alcohol consumption, and the risk of CHD in offspring.

MATERIALS AND METHODS

An observational case-control study was conducted in Lebanon, with 279 participants, aiming to investigate potential risk factors for CHD. We included children with confirmed CHD, born between 2012 and 2022. Controls born in the same timeframe were selected randomly from the general population using online questionnaire forms. Mean age of children included was 6 years old (0-10). The pre-conceptional PA was assessed using the Global Physical Activity Questionnaire validated in Arabic. In addition, paternal smoking, alcohol consumption, and maternal risk factors were collected.

RESULTS

The study included 128 CHD cases (45.9%) and their parents, as well as 151 healthy infants (54.1%) and their parents. There were no statistically significant variations in the alcohol consumption noted between the fathers in the case and control groups (p = 0.18). The paternal involvement in recreational-related PA during the peri-conception period was associated with a reduced risk of the CHD development in offspring by 46.9% (OR = 0.531, 95% CI: 0.301-0.936, p = 0.029). Additionally, increasing paternal total sitting time by 1 h above the average, which was approximately 260 min (4 h), increased the risk of CHD in offspring by 0.4% (p = 0.001). Moreover, paternal smoking exhibited an apparent association with a 56% increased risk of offspring developing CHD, notwithstanding that the confidence intervals included the null (OR = 1.56, 95% CI: 0.86-2.8, p = 0.136).

DISCUSSION AND CONCLUSION

This observational study is the first to report a potential association between paternal PA, and CHD in offspring. This study aligns with previous reports, advocating for the paternal engagement in PA and the adoption of healthy lifestyle habits, especially during the critical stages of conception. Such practices are strongly recommended to enhance fertility and promote optimal health for offspring. However, due to the subjectivity in reporting PA and lack of molecular proof, additional prospective and molecular studies are required to validate these findings.

Decrease in Sperm Parameters in the 21st Century: Obesity, Lifestyle, or Environmental Factors? An Updated Narrative Review

Semen quality represents a compelling factor for fertility, and delineating the normal values has proven difficult. In the last four decades, several authors have reported a noticeable decline in sperm parameters. Also, studies investigating 'time to pregnancy' have shown that fecundity begins to be reduced when sperm numbers decrease below 30 million, even though according to the 6th edition of the WHO manual, the normal value is currently 16 million/mL or 39 million per ejaculate. There exists sufficient data to suggest a decline in sperm counts over time, even though the clear reason for this adverse trend is not well established, but some associations have been hypothesised, such as maternal smoking during pregnancy. Additional potential factors have yet to be fully illustrated but involve poor diet, increased obesity, and exposure to environmental toxins. Moreover, the change in environmental conditions and more common exposure to endocrine-disrupting chemicals (EDCs), such as pesticides and herbicides, as well as bisphenol A, phthalates, polychlorinated biphenyls, and heavy metals, starting from prenatal life and continuing into adulthood, may exhibit probable features explaining the reduction in sperm parameters. Therefore, the main goal of this narrative review is to furnish an overview of the possible effects of exposure to EDCs on testicular function and spermatogenesis and, also, to summarise the evidence regarding a decrease in sperm quality and examine its potential consequences.

Gestational and Developmental Contributors of Pediatric MASLD

Pediatric metabolic dysfunction-associated steatotic liver disease (MASLD) is common and can be seen as early as in utero. A growing body of literature suggests that gestational and early life exposures modify the risk of MASLD development in children. These include maternal risk factors, such as poor cardiometabolic health (e.g., obesity, gestational diabetes, rapid weight gain during pregnancy, and MASLD), as well as periconceptional dietary exposures, degree of physical activity, intestinal microbiome, and smoking. Paternal factors, such as diet and obesity, also appear to play a role. Beyond gestation, early life dietary exposures, as well as the rate of infant weight gain, may further modify the risk of future MASLD development. The mechanisms linking parental health and environmental exposures to pediatric MASLD are complex and not entirely understood. In conclusion, investigating gestational and developmental contributors to MASLD is critical and may identify future interventional targets for disease prevention.

Effect of Paternal Body Mass Index on In Vitro Fertilization and Neonatal Outcomes among Oligozoospermia and Asthenospermia Patients

PURPOSE

Male overweight and obesity could affect sperm quality and reproductive health. However, the impact of body mass index (BMI) on assisted reproductive technology (ART) outcomes in oligospermia and/or asthenospermia patients is yet lacking. This study aims to assess the impact of paternal BMI on ART and neonatal outcomes among oligozoospermia and/or asthenospermia patients undergoing in vitro fertilization (IVF)/intracytoplasmic sperm injection (ICSI).

MATERIALS AND METHODS

In this study, 2,075 couples undergoing their first fresh embryo transfer between January 2015 and June 2022 were recruited. Following the World Health Organization's (WHO's) categories, couples were stratified into three cohorts based on paternal BMI: normal weight (18.5-24.9 kg/m²), overweight (25.0-29.9 kg/m²), and obese (≥30.0 kg/m²). Modified Poisson regression models were used to assess the associations of paternal BMI with fertilization, in vitro embryonic development, and pregnancy outcomes. Logistic regression models were performed to investigate the associations of paternal BMI with pregnancy loss and neonatal outcomes. Furthermore, stratified analyses were performed based on fertilization methods, male infertility cause, and maternal BMI.

RESULTS

Higher paternal BMI is associated with a lower likelihood of achieving normal fertilized (p-trend=0.002), Day 3 transferable (p-trend=0.007), and high-quality embryos (p-trend=0.046) in IVF cycles, rather than in ICSI cycles. Paternal BMI of oligospermia or asthenospermia was negatively correlated with day 3 transferable (p-trend=0.013 and 0.030) and high-quality embryos (p-trend=0.024 and 0.027). Moreover, for neonatal outcomes, paternal BMI was positively associated with macrosomia (p-trend=0.019), large for gestational age (LGA) (p-trend=0.031), and very LGA (p-trend=0.045).

CONCLUSIONS

Our data suggested that higher paternal BMI was associated with fetal overgrowth, reduced fertilization, and embryonic development potential. Among males with oligospermia and/or asthenospermia, the impact of overweight and obesity on the choice of fertilization method and the long-term effects on their offspring need to be further investigated.

Male obesity: Associated effects on fertility and the outcomes of offspring

Obesity rates are increasing globally, making it imperative to comprehend the effects of parental obesity on human reproduction. This review aims to highlight the impact of male obesity on reproductive and offspring outcomes. Male obesity has been shown to affect fertility through various mechanisms, including changes in semen quality, difficulty with natural conception, and worsened assisted reproductive technology outcomes. The evidence regarding the impact of male obesity on success of sperm retrieval is conflicting, but all aforementioned adverse effects may be modifiable with weight loss. Moreover, paternal obesity may influence atypical offspring outcomes, such as placental abnormalities and disruptions in fetal development, which may be moderated by epigenetic pathways. Further research is needed to fully understand the complex relationships and underlying mechanisms involved. Gaining more insight into the impact of male obesity on fertility and offspring outcomes can aid in the development of targeted interventions to improve family planning and the health of future generations.

Prenatal Androgen Excess Induces Multigenerational Effects on Female and Male Descendants

Background

It is still unelucidated how hormonal alterations affect developing organisms and their descendants. Particularly, the effects of androgen levels are of clinical relevance as they are usually high in women with Polycystic Ovary Syndrome (PCOS). Moreover, it is still unknown how androgens may affect males' health and their descendants.

Objectives

We aimed to evaluate the multigenerational effect of prenatal androgen excess until a second generation at early developmental stages considering both maternal and paternal effects.

Design And Methods

This is an animal model study. Female rats (F0) were exposed to androgens during pregnancy by injections of 1 mg of testosterone to obtain prenatally hyperandrogenized (PH) animals (F1), leading to a well-known animal model that resembles PCOS features. A control (C) group was obtained by vehicle injections. The PH-F1 animals were crossed with C males (m) or females (f) and C animals were also mated, thus obtaining 3 different mating groups: Cf × Cm, PHf × Cm, Cf × PHm and their offspring (F2).

Results

F1-PHf presented altered glucose metabolism and lipid profile compared to F1-C females. In addition, F1-PHf showed an increased time to mating with control males compared to the C group. At gestational day 14, we found alterations in glucose and total cholesterol serum levels and in the placental size of the pregnant F1-PHf and Cf mated to F1-PHm. The F2 offspring resulting from F1-PH mothers or fathers showed alterations in their growth, size, and glucose metabolism up to early post-natal development in a sex-dependent manner, being the females born to F1-PHf the most affected ones.

Conclusion

androgen exposure during intrauterine life leads to programing effects in females and males that affect offspring health in a sex-dependent manner, at least up-to a second generation. In addition, this study suggests paternally mediated effects on the F2 offspring development.

Excessive Gestational Weight Gain Alters DNA Methylation and Influences Foetal and Neonatal Body Composition

BACKGROUND

Changes in body weight are associated with the regulation of DNA methylation (DNAm). In this study, we investigated the associations between maternal gestational weight gain-related DNAm and foetal and neonatal body composition.

METHODS

Brazilian pregnant women from the Araraquara Cohort Study were followed up during pregnancy, delivery, and after hospital discharge. Women with normal pre-pregnancy BMI were allocated into two groups: adequate gestational weight gain (AGWG, n = 45) and excessive gestational weight gain (EGWG, n = 30). Foetal and neonatal body composition was evaluated via ultrasound and plethysmography, respectively. DNAm was assessed in maternal blood using Illumina Infinium MethylationEPIC BeadChip arrays. Linear regression models were used to explore the associations between DNAm and foetal and neonatal body composition.

RESULTS

Maternal weight, GWG, neonatal weight, and fat mass were higher in the EGWG group. Analysis of DNAm identified 46 differentially methylated positions and 11 differentially methylated regions (DMRs) between the EGWG and AGWG groups. Nine human phenotypes were enriched for these 11 DMRs located in 13 genes (EMILIN1, HOXA5, CPT1B, CLDN9, ZFP57, BRCA1, POU5F1, ANKRD33, HLA-B, RANBP17, ZMYND11, DIP2C, TMEM232), highlighting the terms insulin resistance, and hyperglycaemia. Maternal DNAm was associated with foetal total thigh and arm tissues and subcutaneous thigh and arm fat, as well as with neonatal fat mass percentage and fat mass.

CONCLUSION

The methylation pattern in the EGWG group indicated a risk for developing chronic diseases and involvement of maternal DNAm in foetal lean and fat mass and in neonatal fat mass.

Effects of body mass index on IVF outcomes in different age groups

BACKGROUND

Herein, we aimed to analyse the effects of body mass index (BMI) on the treatment outcomes of in vitro fertilisation (IVF) in a cohort of women undergoing their first IVF cycle.

METHODS

A total of 2311 cycles from 986 women undergoing their first IVF/intracytoplasmic sperm injection cycle with fresh/frozen embryo transfer between January 2018 and December 2021 at the Center of Reproductive Medicine, Shuguang Hospital affiliated to Shanghai University of Traditional Chinese Medicine, were considered in this retrospective cohort study. First, the included patients were classified into four groups based on their BMI: underweight (BMI < 18.5 kg/m2, 78 patients), normal weight (18.5 ≤ BMI < 24 kg/m2, 721patients), overweight (24 ≤ BMI < 28 kg/m2, 147 patients), and obese (BMI ≥ 28 kg/m2, 40 patients). The IVF outcomes included the Gn medication days; Gn dosage; number of retrieved oocytes, mature oocytes, fertilized oocytes, cleavages, and available embryos and high-quality embryos; implantation rate; clinical pregnancy rate and live birth rate. Next, all the obtained data were segregated into three different subgroups according to the patient age: < 30 years, 30-38 years and > 38 years; the IVF pregnancy outcomes were compared among the groups.

RESULTS

Compared with the other three groups, the underweight group had a higher number of fertilized oocytes, cleavage and available embryos and a smaller Gn medication days and required a lower Gn dosage. There was no difference in the number of retrieved oocytes and mature oocytes among the groups. Moreover, compared with the women aged 30-38 years in the overweight group, those in the normal weight group had a significantly higher implantation rate, clinical pregnancy rate and live birth rate (p = 0.013 OR 1.75, p = 0.033 OR 1.735, p = 0.020 OR 1.252 respectively). The clinical pregnancy rate was also significantly higher in those aged 30-38 years in the normal weight group than in the obese group (p = 0.036 OR 4.236).

CONCLUSIONS

Although the BMI can greatly affect the pregnancy outcomes of women aged 30-38 years, it has almost no effects on the outcomes of younger or older women.

Obesity and Male Infertility: True, True, and Unrelated?

While the prevalence of obesity has rapidly increased worldwide, there has also been a notable decline in semen parameters over the last several decades. While obesity can negatively impact reproductive hormones, many studies have sought a link between rising obesity and decreased male fertility potential. Nonetheless, few data support a direct link between the two. The focus on obesity as a causative factor in male infertility can potentially result in patient harm through delayed fertility treatment and missed diagnoses. This review investigates the associations between obesity and male infertility and why a potential direct link has been elusive and may not exist. Additionally, indirect mechanisms that may link the two will be reviewed and treatment options for obese infertile men presenting for evaluation will briefly be discussed.

Developmental origins of health and disease: Impact of paternal nutrition and lifestyle

Most epidemiological and experimental studies have focused on maternal influences on offspring's health. The impact of maternal undernutrition, overnutrition, hypoxia, and stress is linked to adverse offspring outcomes across a range of systems including cardiometabolic, respiratory, endocrine, and reproduction among others. During the past decade, it has become evident that paternal environmental factors are also linked to the development of diseases in offspring. In this article, we aim to outline the current understanding of the impact of male health and environmental exposure on offspring development, health, and disease and explore the mechanisms underlying the paternal programming of offspring health. The available evidence suggests that poor paternal pre-conceptional nutrition and lifestyle, and advanced age can increase the risk of negative outcomes in offspring, via both direct (genetic/epigenetic) and indirect (maternal uterine environment) effects. Beginning at preconception, and during utero and the early life after birth, cells acquire an epigenetic memory of the early exposure which can be influential across the entire lifespan and program a child's health. Potentially not only mothers but also fathers should be advised that maintaining a healthy diet and lifestyle is important to improve offspring health as well as the parental health status. However, the evidence is mostly based on animal studies, and well-designed human studies are urgently needed to verify findings from animal data.

Effects of paternal obesity on maternal-neonatal outcomes and long-term prognosis in adolescents

Objective

This study evaluated whether paternal body mass index (BMI) before pregnancy was a risk factor for maternal-neonatal outcomes and long-term prognosis in offspring.

Methods

This study included 29,518 participants from eight cities in Fujian, China using a stratified cluster random sampling method from May to September 2019. They were divided into four groups based on paternal BMI. Univariate and multivariate logistic regression were used to explore the relationship between paternal BMI groups, maternal-neonatal outcomes, and long-term prognosis in offspring. Further subgroup analysis was conducted to examine the stability of the risk.

Results

The incidences of hypertensive disorder complicating pregnancy (HDCP), cesarean delivery, gestational weight gain (GWG) over guideline, and macrosomia were significantly higher in the paternal overweight and obesity group. Importantly, this study demonstrated that the incidence of asthma, hand-foot-and-mouth disease (HFMD), anemia, dental caries, and obesity of adolescents in paternal obesity increased. Furthermore, logistic regression and subgroup analysis confirm paternal obesity is a risk factor for HDCP, cesarean delivery, and macrosomia. It caused poor long-term prognosis in adolescents, including asthma, dental caries, and HFMD.

Conclusions

Paternal obesity is a risk factor for adverse maternal-neonatal outcomes and poor long-term prognosis in adolescents. In addition to focusing on maternal weight, expectant fathers should pay more attention to weight management since BMI is a modifiable risk factor. Preventing paternal obesity can lead to better maternal and child outcomes. It would provide new opportunities for chronic diseases.

Nutritional, pharmacological, and environmental programming of NAFLD in early life

Nonalcoholic fatty liver disease (NAFLD) is the main liver disease worldwide, and its prevalence in children and adolescents has been increasing in the past years. It has been demonstrated that parental exposure to different conditions, both preconceptionally and during pregnancy, can lead to fetal programming of several metabolic diseases, including NAFLD. In this article, we review some of the maternal and paternal conditions that may be involved in early-life programing of adult NAFLD. First, we describe the maternal nutritional factors that have been suggested to increase the risk of NAFLD in the offspring, such as an obesogenic diet, overweight/obesity, and altered lipogenesis. Second, we review the association of certain vitamin supplementation and the use of some drugs during pregnancy, for instance, glucocorticoids, with a higher risk of NAFLD. Furthermore, we discuss the evidence showing that maternal-fetal pathologies, including gestational diabetes mellitus (GDM), insulin resistance (IR), and intrauterine growth restriction (IUGR), as well as the exposure to environmental contaminants, and the impact of microbiome changes, are important factors in early-life programming of NAFLD. Finally, we review how paternal preconceptional conditions, such as exercise and diet (particularly obesogenic diets), may impact fetal growth and liver function. Altogether, the presented evidence supports the hypothesis that both in utero exposure and parental conditions may influence fetal outcomes, including the development of NAFLD in early life and adulthood. The study of these conditions is crucial to better understand the diverse mechanisms involved in NAFLD, as well as for defining new preventive strategies for this disease.