Parental epigenetic age acceleration and risk of adverse birth outcomes: the Norwegian mother, father and child cohort study.

Background: Few studies have examined associations between maternal epigenetic age acceleration and adverse birth outcomes, and none have investigated paternal epigenetic age acceleration. Our objective was to assess the associations of parental (both maternal and paternal) epigenetic age acceleration in relation to birth outcomes.

Methods: Parental epigenetic age was estimated using seven established epigenetic clocks in 2198 mothers and 2193 fathers from the Norwegian Mother, Father, and Child Cohort Study (MoBa).

Environmental exposures and fecundability: The Norwegian Mother, Father, and Child Cohort study.

Previous studies have linked certain environmental exposures to reduced fecundability, influencing exposure recommendations. We continue to encounter numerous environmental exposures in our everyday lives, and further evidence is needed regarding their effects on fecundability. We evaluated associations between various self-reported environmental exposures and fecundability, measured as time to pregnancy, in 64,942 women and 53,219 men participating in the Norwegian Mother, Father, and Child Cohort study (MoBa).

Female Infertility and Neurodevelopmental Disorders in Children: associations and evidence for familial confounding in Denmark.

Importance: Existing research suggests the impact of infertility on the risk of neurodevelopmental disorders in children, however, studies to date have failed to separate the impact of male and female infertility, often blurring the lines with proxies that encompass all forms of infertility. Moreover, while both health conditions co-occurring with infertility and genetic factors operating upstream have been suggested to influence the association between infertility and child outcomes, their roles and potential impact on observed associations remain unclear.

Objective: The objectives of this study are to investigate the relationship between female infertility and autism in the child, differentiating it from the effects of male and the couple infertility; consider the role of various maternal and birth factors in the association; and examine the effects of shared familial confounders on the association.

Sibling relatedness and pubertal development in girls and boys: A population-based cohort study.

Purpose: To investigate the association between sibling relatedness and pubertal development in girls and boys.

Methods: This cohort study consisted of 10,657 children from the Puberty Cohort, Denmark. Information on sibling relatedness was obtained by self-report.

Maternal coffee consumption and biomarkers of reproductive health in young, adult sons: a cohort study.

It has been proposed that poor semen quality may have its origins from fetal programming due to environmental factors. We investigated whether maternal coffee consumption during early pregnancy was associated with biomarkers of reproductive health in adult sons in the Fetal Programming of Semen Quality (FEPOS) cohort. In 2017-2019, 1058 young men provided a semen and blood sample and self-measured their testis volume.

Maternal stress in pregnancy and pubertal timing in girls and boys: a cohort study.

Objective: To investigate whether maternal stress in pregnancy is associated with pubertal timing in girls and boys and to explore potential mediation by childhood body mass index (BMI) and childhood psychosocial stress.

Design: Cohort study.

Setting: Not applicable.

Maternal intake of paracetamol during pregnancy and biomarkers of male fecundity in young adult sons.

Paracetamol is suggested to have endocrine disrupting properties possibly affecting fetal programming of reproductive health that might lead to impaired semen quality and changes in reproductive hormones. In this longitudinal study, we included 1058 young adult men born 1998-2000 into the Danish National Birth Cohort with follow-up at 18-21 years of age. The exposure, maternal intake of paracetamol, was modelled in three ways: dichotomized, trimester-specific, and as duration of exposure categorized into: short (1-2 weeks), medium (3-9 weeks) or long duration (>9 weeks) vs.

Congenital Tooth Agenesis and Risk of Early-Onset Cancer.

Importance: There is some evidence that tooth agenesis (congenital absence of 1 or more teeth) is associated with cancer risk, especially carcinomas of the colon and ovaries, but results of previous studies are conflicting, and associations have not yet been evaluated in a population-based setting.

Objective: To examine the association between tooth agenesis and specific cancer types before 40 years of age.

Design, Setting, And Participants: This population-based cohort study used linking data from nationwide registries in Denmark to assess all Danish live-born singletons born from January 1, 1977, to December 31, 2018, and followed up for up to 40 years.

Maternal use of nitrosatable drugs during pregnancy and adult male reproductive health: A population-based cohort study.

Background: Prenatal exposures to xenobiotics during the masculinization programming window are suggested to impact male fecundity later in life. Frequently used nitrosatable drugs, such as penicillins and beta2-agonists, contain amines or amides that may form teratogenic compounds in reaction with nitrite.

Objectives: We explored whether maternal nitrosatable drug use during gestation was associated with biomarkers of male fecundity in adulthood; moreover, the potential modifiable effect of nitrate and vitamin intake was investigated.

Birth by caesarean section and semen quality in adulthood: a Danish population-based cohort study.

Background: The caesarean section (CS) rate has increased worldwide and there is an increasing public and scientific interest in the potential long-term health consequences for the offspring. CS is related to persistent aberrant microbiota colonization in the offspring, which may negatively interfere with sex hormone homeostasis and thus potentially affect the reproductive health. It remains unknown whether adult sons' semen quality is affected by CS.

Characteristics of Puberty in a Population-Based Sample of Danish Adolescents.

Purpose: To describe the duration, timing, tempo, and synchronicity of puberty, as well as the correlation between timing and tempo of puberty.

Methods: Overall, 15,819 of 22,439 invited children participated in the Puberty Cohort within the Danish National Birth Cohort. Participants completed a web-based questionnaire every 6 months through maturation with questions on current pubertal status.

Sleep duration and biomarkers of fecundity in young men: a cross-sectional study from a population-based cohort.

Background: Poor male fecundity is of concern and warrants the identification of potential modifiable risk factors. Short and long sleep duration might be risk factors for poor male fecundity although evidence in this research field is inconsistent.

Objectives: To investigate the association between sleep duration and biomarkers of male fecundity in young men.

Maternal pre-pregnancy BMI and reproductive health in adult sons: a study in the Danish National Birth Cohort.

Study Question: Is maternal pre-pregnancy BMI associated with semen quality, testes volume, and reproductive hormone levels in sons?

Summary Answer: Maternal pre-pregnancy BMI was associated with an altered reproductive hormone profile in young adult sons, characterized by higher levels of oestradiol, LH, and free androgen index (FAI) and lower levels of sex hormone-binding globulin (SHBG) in sons born of mothers with pre-pregnancy overweight and obesity.

What Is Known Already: Evidence suggests that maternal pre-pregnancy BMI may influence reproductive health later in life. Only one pilot study has investigated the association between maternal pre-pregnancy BMI and reproductive health outcomes in sons, suggesting that a high BMI was associated with impaired reproductive function in the adult sons.

Paternal pre-conceptional smoking and semen quality in the adult son.

Background: Growing evidence suggests intergenerational effects of paternal pre-conceptional smoking through the germ line, but its specific impact on offspring semen quality remains uncertain because of challenges in isolating paternal exposure from maternal passive smoking or underreporting.

Methods: We reran previous analyses estimating differences in semen parameters and testicular size according to paternal smoking in 867 young adult men, adding first-trimester maternal plasma cotinine to the original adjustment for maternal self-reported smoking. We also estimated differences in sperm DNA fragmentation.

Prenatal exposure to nitrosatable drugs and timing of puberty in sons and daughters: A nationwide cohort study.

Background: N-nitroso compounds (NOCs) can be formed by endogenous reactions between nitrosatable drugs and nitrite. Animal studies have found that several NOCs are teratogenic, and epidemiological studies report associations between prenatal exposure to nitrosatable drugs and adverse birth outcomes. It is unknown whether prenatal exposure to nitrosatable drugs is harmful to the child's reproductive health, including pubertal development.

Maternal Intake of Vitamin D Supplements during Pregnancy and Pubertal Timing in Children: A Population-Based Follow-Up Study.

Maternal vitamin D may be important for several organ systems in the offspring, including the reproductive system. In this population-based follow-up study of 12,991 Danish boys and girls born 2000-2003, we investigated if maternal intake of vitamin D supplements during pregnancy was associated with pubertal timing in boys and girls. Information on maternal intake of vitamin D supplements was obtained by self-report in mid-pregnancy.

Parental age at birth and biomarkers of fecundity in young Danish men.

Background: High parental age is associated with adverse birth and genetic outcomes, but little is known about fecundity in male offspring.

Objectives: We investigated if high parental age at birth was associated with biomarkers of male fecundity in a large population-based sample of young men.

Materials And Methods: We conducted a study of 1057 men from the Fetal Programming of Semen Quality (FEPOS) cohort, a sub-cohort of sons born 1998-2000 into the Danish National Birth Cohort.

Measures of fetal growth and preterm birth and risk of endometriosis and adenomyosis in adult life: a systematic review and meta-analysis.

Introduction: Exposures in utero are suggested to play a role in the etiology of endometriosis and adenomyosis, although the current evidence is inconclusive. Knowledge about potential prenatal programming and early life exposures that may affect this risk is of high importance, to focus potential preventive strategies for the diseases already during pregnancy. The aim of this study was to review systematically the literature of the association between measures of fetal growth and preterm birth and endometriosis and adenomyosis in adult life.

Prenatal Exposure to Nitrate in Drinking Water and Adverse Health Outcomes in the Offspring: a Review of Current Epidemiological Research.

Purpose Of Review: Recently, several epidemiological studies have investigated whether prenatal exposure to nitrate from drinking water may be harmful to the fetus, even at nitrate levels below the current World Health Organization drinking water standard. The purpose of this review was to give an overview of the newest knowledge on potential health effects of prenatal exposure to nitrate.

Recent Findings: We included 13 epidemiological studies conducted since 2017.

Timing of puberty in relation to semen characteristics, testicular volume, and reproductive hormones: a cohort study.

Objective: To investigate whether the timing of puberty is associated with semen characteristics, testicular volume, and reproductive hormone levels.

Design: Cohort study.

Setting: Not applicable.

Maternal alcohol intake in early pregnancy and biomarkers of fecundity in adult sons: A cohort study.

Male fecundity may be largely determined through fetal programming and therefore potentially be sensitive to exposure to maternal alcohol intake during pregnancy. We investigated whether maternal alcohol intake in early pregnancy was associated with biomarkers of fecundity in adult sons. In total, 1058 sons from the Fetal Programming of Semen Quality (FEPOS) cohort nested in the Danish National Birth Cohort (DNBC) provided blood and semen samples at around 19 years of age.