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Huang K, Gaml-Sørensen A, Brix N, Ernst A, Arendt LH, Bonde JPE, Hougaard KS, Toft G, Tøttenborg SS, Ramlau-Hansen CH. Birth by caesarean section and semen quality in adulthood: a Danish population-based cohort study. Reprod Health 2024; 21:33. [PMID: 38459587 PMCID: PMC10921573 DOI: 10.1186/s12978-024-01761-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2022] [Accepted: 02/23/2024] [Indexed: 03/10/2024] Open
Abstract
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. We hypothesize that CS is associated with lower semen quality. METHODS This study was based on the Fetal Programming of Semen Quality cohort (FEPOS, enrolled from 2017 to 2019) nested within the Danish National Birth Cohort (DNBC, enrolled from 1996 to 2002). A total of 5697 adult sons of mothers from the DNBC were invited to the FEPOS cohort, and 1044 young men participated in this study. Information on mode of delivery was extracted from the Danish Medical Birth Registry, and included vaginal delivery, elective CS before labor, emergency CS during labor and unspecified CS. The young men provided a semen sample for analysis of semen volume, sperm concentration, motility and morphology. Negative binomial regression models were applied to examine the association between CS and semen characteristics with estimation of relative differences in percentages with 95% confidence intervals (CIs). RESULTS Among included sons, 132 (13%) were born by CS. We found a slightly lower non-progressive sperm motility (reflecting higher progressive sperm motility) among sons born by CS compared to sons born by vaginal delivery [relative difference (95% CI): - 7.5% (- 14.1% to - 0.4%)]. No differences were observed for other sperm characteristics. When CS was further classified into elective CS, emergency CS and unspecified CS in a sensitivity analysis, no significant differences in non-progressive motility were observed among sons born by any of the three types of CS compared to sons born vaginally. CONCLUSIONS This large population-based cohort study found no significant evidence for an adverse effect on semen quality in adult sons born by CS.
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Affiliation(s)
- Kun Huang
- Department of Maternal, Child and Adolescent Health, School of Public Health, Anhui Medical University, No 81 Meishan Road, Hefei, 230032, China.
- MOE Key Laboratory of Population Health Across Life Cycle, Hefei, 230032, China.
- NHC Key Laboratory of Study On Abnormal Gametes and Reproductive Tract, Hefei, 230032, China.
- Anhui Provincial Key Laboratory of Environment and Population Health Across the Life Course, Hefei, 230032, China.
- Department of Public Health, Research Unit for Epidemiology, Aarhus University, 8000, Aarhus C, Denmark.
| | - Anne Gaml-Sørensen
- Department of Public Health, Research Unit for Epidemiology, Aarhus University, 8000, Aarhus C, Denmark
| | - Nis Brix
- Department of Public Health, Research Unit for Epidemiology, Aarhus University, 8000, Aarhus C, Denmark
- Department of Clinical Genetics, Aarhus University Hospital, 8200, Aarhus N, Denmark
| | - Andreas Ernst
- Department of Public Health, Research Unit for Epidemiology, Aarhus University, 8000, Aarhus C, Denmark
- Department of Urology, Aarhus University Hospital, 8200, Aarhus N, Denmark
| | - Linn Håkonsen Arendt
- Department of Public Health, Research Unit for Epidemiology, Aarhus University, 8000, Aarhus C, Denmark
- Department of Obstetrics and Gynecology, Aarhus University Hospital, 8200, Aarhus N, Denmark
| | - Jens Peter Ellekilde Bonde
- Department of Occupational and Environmental Medicine, Bispebjerg and Frederiksberg Hospital, University of Copenhagen, 2400, Copenhagen, NV, Denmark
- Department of Public Health, University of Copenhagen, 1353, Copenhagen K, Denmark
| | - Karin Sørig Hougaard
- Department of Public Health, University of Copenhagen, 1353, Copenhagen K, Denmark
- National Research Centre for the Working Environment, 2100, Copenhagen, OE, Denmark
| | - Gunnar Toft
- Steno Diabetes Center Aarhus, Aarhus University Hospital, 8200, Arhus N, Denmark
| | - Sandra Søgaard Tøttenborg
- Department of Occupational and Environmental Medicine, Bispebjerg and Frederiksberg Hospital, University of Copenhagen, 2400, Copenhagen, NV, Denmark
- Department of Public Health, University of Copenhagen, 1353, Copenhagen K, Denmark
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Gaml-Sørensen A, Thomsen AH, Tøttenborg SS, Brix N, Hougaard KS, Toft G, Håberg SE, Myrskylä M, Bonde JP, Ramlau-Hansen CH. Maternal pre-pregnancy BMI and reproductive health in adult sons: a study in the Danish National Birth Cohort. Hum Reprod 2024; 39:219-231. [PMID: 37935951 PMCID: PMC10767916 DOI: 10.1093/humrep/dead230] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2023] [Revised: 10/12/2023] [Indexed: 11/09/2023] Open
Abstract
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. STUDY DESIGN, SIZE, DURATION A population-based follow-up study of 1058 young men from the Fetal Programming of Semen Quality (FEPOS) cohort nested within the Danish National Birth Cohort (DNBC), 1998-2019, was carried out. PARTICIPANTS/MATERIALS, SETTING, METHODS In total, 1058 adult sons (median age 19 years, 2 months), born 1998-2000 by mothers included in the DNBC, participated in FEPOS. At a clinical examination, they provided a semen and blood sample, measured their testes volume, and had height and weight measured. Maternal pre-pregnancy BMI was obtained by self-report in early pregnancy. Semen characteristics, testes volume, and reproductive hormone levels were analysed according to maternal pre-pregnancy BMI categories and as restricted cubic splines using negative binomial and ordinary least square regression models. Mediation analyses examined potential mediation by the sons' birthweight, pubertal timing, fat mass, and BMI. Additional analyses investigated the role of paternal BMI in the potential associations between maternal BMI and reproductive health outcomes. MAIN RESULTS AND THE ROLE OF CHANCE We found no consistent associations between maternal pre-pregnancy BMI and semen characteristics or testes volume. Sons of mothers with higher pre-pregnancy BMI had higher oestradiol and lower SHBG levels, both in a dose-dependent manner. Sons of mothers with pre-pregnancy obesity (≥30 kg/m2) had higher LH levels and a higher FAI than sons born by mothers with normal pre-pregnancy BMI (18.5-24.9 kg/m2). The mediation analyses suggested that the effect of maternal pre-pregnancy BMI on higher levels of oestrogen, LH, and FAI was partly mediated by the sons' birthweight, in addition to adult fat mass and BMI measured at the clinical examination, whereas most of the effect on lower levels of SHBG was primarily mediated by the sons' own fat mass and BMI. Paternal BMI was not a strong confounder of the associations in this study. LIMITATIONS, REASONS FOR CAUTION This study was based in a population-based cohort with a low prevalence of overweight and obesity in both mothers and adult sons. Some men (10%) had blood for reproductive hormone assessment drawn in the evening. While several potential confounding factors were accounted for, this study's inherent risk of residual and unmeasured confounding precludes provision of causal estimates. Therefore, caution should be given when interpreting the causal effect of maternal BMI on sons' reproductive health. WIDER IMPLICATIONS OF THE FINDINGS Given the widespread occurrence of overweight and obesity among pregnant women, it is imperative to thoroughly examine the potential consequences for reproductive hormone levels in adult sons. The potential effects of maternal pre-pregnancy obesity on sons' reproductive hormone profile may potentially be partly avoided by the prevention of overweight and obesity in the sons. STUDY FUNDING/COMPETING INTEREST(S) The project was funded by the Lundbeck Foundation (R170-2014-855), the Capital Region of Denmark, Medical doctor Sofus Carl Emil Friis and spouse Olga Doris Friis's Grant, Axel Muusfeldt's Foundation (2016-491), AP Møller Foundation (16-37), the Health Foundation, Dagmar Marshall's Fond, Aarhus University, Independent Research Fund Denmark (9039-00128B), and the European Union (ERC, BIOSFER, 101071773). Views and opinions expressed are, however, those of the authors only and do not necessarily reflect those of the European Union or the European Research Council. Neither the European Union nor the granting authority can be held responsible. The authors declare that they have no conflict of interest. TRIAL REGISTRATION NUMBER N/A.
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Affiliation(s)
- Anne Gaml-Sørensen
- Department of Public Health, Research Unit for Epidemiology, Aarhus University, Aarhus, Denmark
| | - Anne Hjorth Thomsen
- Department of Public Health, Research Unit for Epidemiology, Aarhus University, Aarhus, Denmark
| | - Sandra Søgaard Tøttenborg
- Department of Occupational and Environmental Medicine, Copenhagen University Hospital—Bispebjerg and Frederiksberg, Copenhagen, Denmark
- Department of Public Health, Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Nis Brix
- Department of Public Health, Research Unit for Epidemiology, Aarhus University, Aarhus, Denmark
- Department of Clinical Genetics, Aarhus University Hospital, Aarhus, Denmark
| | - Karin Sørig Hougaard
- Department of Public Health, Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark
- National Research Centre for Working Environment, Copenhagen, Denmark
| | - Gunnar Toft
- Steno Diabetes Center Aarhus, Aarhus University Hospital, Aarhus, Denmark
| | - Siri Eldevik Håberg
- Centre for Fertility and Health, Norwegian Institute of Public Health, Oslo, Norway
| | - Mikko Myrskylä
- Max Planck Institute for Demographic Research, Rostock, Germany
- Center for Social Data Science and Population Research Unit, University of Helsinki, Helsinki, Finland
- Max Planck—University of Helsinki Center for Social Inequalities in Population Health, Rostock, Germany
| | - Jens Peter Bonde
- Department of Occupational and Environmental Medicine, Copenhagen University Hospital—Bispebjerg and Frederiksberg, Copenhagen, Denmark
- Department of Public Health, Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark
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Gaml-Sørensen A, Frølich MK, Brix N, Ernst A, Bonde JPE, Hougaard KS, Tøttenborg SS, Clemmensen PJ, Toft G, Ramlau-Hansen CH. Sleep duration and biomarkers of fecundity in young men: a cross-sectional study from a population-based cohort. Andrology 2023. [PMID: 37985426 DOI: 10.1111/andr.13560] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2023] [Revised: 10/05/2023] [Accepted: 11/09/2023] [Indexed: 11/22/2023]
Abstract
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. MATERIALS AND METHODS We conducted a cross-sectional study of 1,055 young men from the Fetal Programming of Semen Quality (FEPOS) cohort, Denmark, 2017-2019. Sleep duration was obtained from an online survey answered by the participants prior to the clinical visit, where semen and blood samples were obtained, and testis volume was self-assessed using an Orchidometer. Percentage differences in semen characteristics, testes volume, and reproductive hormone levels were analysed according to sleep duration using multivariable negative binomial regression models. Sleep duration was dichotomised (recommended (6-9 h/night) versus deviant sleep) and visualised continuously as restricted cubic spline plots. RESULTS Deviation from recommended sleep duration was associated with higher high DNA stainability (HDS) of 5% (95% CI: -1%; 13%), higher testosterone of 3% (95% CI: 0%; 7%) and higher free androgen index (FAI) of 6% (95% CI: 0%; 13%). The spline plots overall supported these results, suggesting u-shaped associations between sleep duration and HDS, testosterone and FAI, a linear association between sleep duration and semen volume and sex hormone binding globulin (SHBG) and an inverse u-shaped association with normal morphology. DISCUSSION Information on sleep duration was obtained by self-report in broad categories with at least 3 h intervals. We were not able to investigate short or long sleep duration separately, since only few participants reported this. CONCLUSION Sleep duration was associated with some biomarkers of fecundity in young men. Maintaining a recommended sleep duration may thus be beneficial for young men with regard to reproductive health.
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Affiliation(s)
| | | | - Nis Brix
- Department of Public Health, Aarhus University, Aarhus C, Denmark
- Department of Clinical Genetics, Aarhus University Hospital, Aarhus N, Denmark
| | - Andreas Ernst
- Department of Public Health, Aarhus University, Aarhus C, Denmark
- Department of Urology, Aarhus University Hospital, Aarhus, Denmark
| | - Jens Peter Ellekilde Bonde
- Department of Occupational and Environmental Medicine, Bispebjerg and Frederiksberg Hospital, University of Copenhagen, Copenhagen NV, Denmark
- Department of Public Health, University of Copenhagen, Copenhagen K, Denmark
| | - Karin Sørig Hougaard
- Department of Public Health, University of Copenhagen, Copenhagen K, Denmark
- National Research Centre for the Working Environment, Copenhagen Oest, Denmark
| | - Sandra Søgaard Tøttenborg
- Department of Occupational and Environmental Medicine, Bispebjerg and Frederiksberg Hospital, University of Copenhagen, Copenhagen NV, Denmark
- Department of Public Health, University of Copenhagen, Copenhagen K, Denmark
| | | | - Gunnar Toft
- Steno Diabetes Center Aarhus, Aarhus University Hospital, Aarhus N, Denmark
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Gaml-Sørensen A, Brix N, Ernst A, Lunddorf LLH, Lindh C, Toft G, Henriksen TB, Arah OA, Ramlau-Hansen CH. The estimated effect of season and vitamin D in the first trimester on pubertal timing in girls and boys: a cohort study and an instrumental variable analysis. Int J Epidemiol 2023; 52:1328-1340. [PMID: 37178177 PMCID: PMC11046010 DOI: 10.1093/ije/dyad060] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2022] [Accepted: 04/25/2023] [Indexed: 05/15/2023] Open
Abstract
BACKGROUND Season of birth has been associated with age at menarche. Maternal vitamin D levels in pregnancy may explain this effect. We investigated whether the season of first trimester or maternal 25-hydroxyvitamin D3 [25(OH)D3] levels were associated with pubertal timing in children. METHODS We conducted a follow-up study of 15 819 children born in 2000-03 from the Puberty Cohort, nested in the Danish National Birth Cohort (DNBC). Mean differences in attaining numerous pubertal markers, including a combined estimate for the average age at attaining all pubertal markers, were estimated for low (November-April) relative to high (May-October) sunshine exposure season in the first trimester using multivariable interval-censored regression models. Moreover, we conducted a two-sample instrumental variable analysis using season as an instrument for maternal first-trimester 25(OH)D3 plasma levels obtained from a non-overlapping subset (n = 827) in the DNBC. RESULTS For the combined estimate, girls and boys of mothers who had their first trimester during November-April had earlier pubertal timing than girls and boys of mothers whose first trimester occurred during May-October: -1.0 months (95% CI: -1.7 to -0.3) and -0.7 months (95% CI: -1.4 to -0.1), respectively. In the instrumental variable analysis, girls and boys also had earlier pubertal timing: respectively, -1.3 months (95% CI: -2.1 to -0.4) and -1.0 months (95% CI: -1.8 to -0.2) per SD (22 nmol/L) decrease in 25(OH)D3. CONCLUSIONS Both first pregnancy trimester during November-April and lower 25(OH)D3 were associated with earlier pubertal timing in girls and boys.
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Affiliation(s)
- Anne Gaml-Sørensen
- Department of Public Health, Research Unit for Epidemiology, Bartholins Allé 2, Aarhus University, 8000, Aarhus C, Denmark
- Department of Epidemiology, Fielding School of Public Health, University of California, Los Angeles (UCLA), 650 Charles E Young Dr. South, Los Angeles, CA, 90095, USA
| | - Nis Brix
- Department of Public Health, Research Unit for Epidemiology, Bartholins Allé 2, Aarhus University, 8000, Aarhus C, Denmark
- Department of Clinical Genetics, Aarhus University Hospital, Brendstrupgårdsvej 21 C, 8200, Aarhus N, Denmark
| | - Andreas Ernst
- Department of Public Health, Research Unit for Epidemiology, Bartholins Allé 2, Aarhus University, 8000, Aarhus C, Denmark
- Department of Urology, Aarhus University Hospital, Palle Juul-Jensens, Boulevard 35, 8200, Aarhus N, Denmark
| | - Lea Lykke Harrits Lunddorf
- Department of Public Health, Research Unit for Epidemiology, Bartholins Allé 2, Aarhus University, 8000, Aarhus C, Denmark
| | - Christian Lindh
- Division of Occupational and Environmental Medicine, Lund University, Medicon Village, Byggnad 402 A, 22363, Lund, Sweden
| | - Gunnar Toft
- Steno Diabetes Center Aarhus, Aarhus University Hospital, Hedeager 3, 8200, Aarhus N, Denmark
| | - Tine Brink Henriksen
- Perinatal Epidemiology Research Unit, Aarhus University and Department of Paediatrics and Adolescent Medicine, Aarhus University Hospital, Palle Juul-Jensens Boulevard 103, 8200, Aarhus N, Denmark
| | - Onyebuchi A Arah
- Department of Public Health, Research Unit for Epidemiology, Bartholins Allé 2, Aarhus University, 8000, Aarhus C, Denmark
- Department of Epidemiology, Fielding School of Public Health, University of California, Los Angeles (UCLA), 650 Charles E Young Dr. South, Los Angeles, CA, 90095, USA
- Department of Statistics, Division of Physical Sciences, UCLA College, Boelter Hall 9434, Los Angeles, CA, 90095, USA
| | - Cecilia Høst Ramlau-Hansen
- Department of Public Health, Research Unit for Epidemiology, Bartholins Allé 2, Aarhus University, 8000, Aarhus C, Denmark
- Department of Epidemiology, Fielding School of Public Health, University of California, Los Angeles (UCLA), 650 Charles E Young Dr. South, Los Angeles, CA, 90095, USA
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Brix N, Gaml-Sørensen A, Ernst A, Arendt LH, Lunddorf LLH, Toft G, Tøttenborg SS, Hærvig KK, Høyer BB, Hougaard KS, Bonde JPE, Ramlau-Hansen CH. Timing of puberty in relation to semen characteristics, testicular volume, and reproductive hormones: a cohort study. Fertil Steril 2023; 120:823-833. [PMID: 37257718 DOI: 10.1016/j.fertnstert.2023.05.164] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2023] [Revised: 05/04/2023] [Accepted: 05/23/2023] [Indexed: 06/02/2023]
Abstract
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. PATIENTS The Danish National Birth Cohort and its subcohort, the Fetal Programming of Semen Quality cohort of 1,058 young men. INTERVENTION(S) Self-reported information on the timing (younger, same age, older than peers) of the pubertal markers: voice break (primary exposure), pubic hair growth, regular shaving, and axillary hair growth. MAIN OUTCOME MEASURES(S) We estimated the relative differences with 95% confidence intervals for semen characteristics (semen volume, sperm concentration, total sperm count, sperm motility, percentage of morphologically normal spermatozoa), testicular volume, and reproductive hormones (follicle stimulating hormone [FSH], luteinizing hormone, sex hormone-binding globulin [SHBG], testosterone, estradiol, and free androgen index [FAI]) obtained at a median age of 19.2 years according to timing of pubertal development. RESULT(S) Compared with men reporting voice break "same age as peers," men reporting voice break "older than peers" tended to have lower total sperm count (-12% [-25%, 4%]) and lower percent morphologically normal spermatozoa (-10% [-20%, 2%]), whereas men reporting voice break "younger than peers" tended to have a lower proportion of nonprogressive and immotile spermatozoa (-6% [-13%, 1%]) and larger testicular volume (7% [1%, 13%]). The pattern was less consistent for the other pubertal markers. For reproductive hormones, voice break "older than peers" tended to have higher FSH levels (24% [-1%, 55%]), higher SHBG levels (7% [0, 15%]), lower estradiol levels (-14% [-23%, -5%]), and lower FAI (-8% [-14%, -1%]), whereas voice break "younger than peers" tended to have higher luteinizing hormone levels (4% [-2%, 11%]), higher testosterone levels (5% [0%, 11%]), higher estradiol levels (17% [6%, 29%]), and higher FAI (4% [-2%, 11%]). When the categorical pubertal markers were analyzed as a linear term to assess dose dependence, older age at pubertal development was associated with higher FSH levels, higher SHBG levels, lower testosterone levels, lower estradiol levels, and lower FAI for most pubertal markers. CONCLUSION(S) These results lend weak support to the hypothesis that older age at pubertal development is associated with markers of reduced male fecundity, especially reproductive hormone levels, although associations with semen characteristics and testicular volume were statistically insignificant.
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Affiliation(s)
- Nis Brix
- Department of Public Health, Research Unit for Epidemiology, Aarhus University, Aarhus, Denmark; Department of Clinical Genetics, Aarhus University Hospital, Aarhus, Denmark.
| | - Anne Gaml-Sørensen
- Department of Public Health, Research Unit for Epidemiology, Aarhus University, Aarhus, Denmark
| | - Andreas Ernst
- Department of Public Health, Research Unit for Epidemiology, Aarhus University, Aarhus, Denmark; Department of Urology, Aarhus University Hospital, Aarhus, Denmark
| | - Linn Håkonsen Arendt
- Department of Public Health, Research Unit for Epidemiology, Aarhus University, Aarhus, Denmark; Department of Obstetrics and Gynecology, Aarhus University Hospital, Aarhus, Denmark
| | | | - Gunnar Toft
- Steno Diabetes Center Aarhus, Aarhus University Hospital, Aarhus, Denmark
| | - Sandra S Tøttenborg
- Department of Occupational and Environmental Medicine, Bispebjerg and Frederiksberg Hospital, Copenhagen, Denmark; Department of Public Health, University of Copenhagen, Copenhagen, Denmark
| | - Katia Keglberg Hærvig
- Department of Occupational and Environmental Medicine, Bispebjerg and Frederiksberg Hospital, Copenhagen, Denmark
| | - Birgit Bjerre Høyer
- Department of Public Health, Research Unit for Epidemiology, Aarhus University, Aarhus, Denmark; Open Patient data Explorative Network, Odense University Hospital, Odense, Denmark
| | - Karin S Hougaard
- Department of Public Health, University of Copenhagen, Copenhagen, Denmark; National Research Centre for the Working Environment, Copenhagen, Denmark
| | - Jens Peter E Bonde
- Department of Occupational and Environmental Medicine, Bispebjerg and Frederiksberg Hospital, Copenhagen, Denmark; Department of Public Health, University of Copenhagen, Copenhagen, Denmark
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Ernst A, Brix N, Gaml-Sørensen A, Arendt LH, Toft G, Tøttenborg SS, Hougaard KS, Bonde JPE, Ramlau-Hansen CH. Parental age at birth and biomarkers of fecundity in young Danish men. Andrology 2023. [PMID: 37750236 DOI: 10.1111/andr.13536] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2023] [Revised: 08/16/2023] [Accepted: 09/12/2023] [Indexed: 09/27/2023]
Abstract
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. Semen characteristics and reproductive hormone concentrations were measured in samples provided by the men 2017-2019. Testis volume was determined by self-measurement. Data on the parental age was drawn from registers. Adjusted relative difference in percentage with 95% confidence intervals were estimated for each outcome according to pre-specified maternal and paternal age groups (< 30 (reference), 30-34 and ≥ 35) as well as for combinations of parental age groups, using multivariable negative binomial regression models. RESULTS We did not observe consistent associations between parental age and biomarkers of fecundity, although sons of mothers ≥ 35 years had lower sperm concentration (-15% (95% CI: -30, 3)) and total sperm count (-10% (95% CI: -25, 9)). The analysis with parental age combinations showed lower sperm concentration with high age of the parents (both ≥ 35 years: -27%, 95% CI: -40, -19) when compared to the reference where both parents were below 30 years. DISCUSSION AND CONCLUSION We found no strong association between higher parental age and biomarkers of fecundity in young men. However, we cannot exclude poorer semen characteristics in sons born by older mothers or with high age of both parents.
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Affiliation(s)
- Andreas Ernst
- Research Unit for Epidemiology, Department of Public Health, Aarhus University, Aarhus, Denmark
- Department of Urology, Aarhus University Hospital, Aarhus, Denmark
| | - Nis Brix
- Research Unit for Epidemiology, Department of Public Health, Aarhus University, Aarhus, Denmark
- Department of Clinical Genetics, Aarhus University Hospital, Aarhus, Denmark
| | - Anne Gaml-Sørensen
- Research Unit for Epidemiology, Department of Public Health, Aarhus University, Aarhus, Denmark
| | - Linn Håkonsen Arendt
- Research Unit for Epidemiology, Department of Public Health, Aarhus University, Aarhus, Denmark
| | - Gunnar Toft
- Steno Diabetes Center Aarhus, Aarhus University Hospital, Aarhus, Denmark
| | - Sandra Søgaard Tøttenborg
- Department of Occupational and Environmental Medicine, Copenhagen University Hospital-Bispebjerg and Frederiksberg, Copenhagen, Denmark
- Department of Public Health, University of Copenhagen, Copenhagen, Denmark
| | - Karin Søring Hougaard
- Department of Public Health, University of Copenhagen, Copenhagen, Denmark
- National Research Centre for the Working Environment, Copenhagen, Denmark
| | - Jens Peter Ellekilde Bonde
- Department of Occupational and Environmental Medicine, Copenhagen University Hospital-Bispebjerg and Frederiksberg, Copenhagen, Denmark
- Department of Public Health, University of Copenhagen, Copenhagen, Denmark
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Gaml-Sørensen A, Brix N, Lunddorf LLH, Ernst A, Høyer BB, Toft G, Henriksen TB, Ramlau-Hansen CH. Maternal Intake of Vitamin D Supplements during Pregnancy and Pubertal Timing in Children: A Population-Based Follow-Up Study. Nutrients 2023; 15:4039. [PMID: 37764822 PMCID: PMC10536415 DOI: 10.3390/nu15184039] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2023] [Revised: 09/14/2023] [Accepted: 09/15/2023] [Indexed: 09/29/2023] Open
Abstract
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. Self-reported information on the current status of various pubertal milestones was obtained every six months throughout puberty. Mean differences in months at attaining each pubertal milestone and an average estimate for the mean difference in attaining all pubertal milestones were estimated according to maternal intake of vitamin D supplements using multivariable interval-censored regression models. Lower maternal intake of vitamin D supplements was associated with later pubertal timing in boys. For the average estimate, boys had 0.5 months (95% CI 0.1; 0.9) later pubertal timing per 5 µg/day lower maternal vitamin D supplement intake. Maternal intake of vitamin D supplements was not associated with pubertal timing in girls. Spline plots and sensitivity analyses supported the findings. Whether the observed association with boys' pubertal timing translates into an increased risk of disease in adulthood is unknown.
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Affiliation(s)
- Anne Gaml-Sørensen
- Department of Public Health, Research Unit for Epidemiology, Aarhus University, Bartholins Alle 2, 8000 Aarhus C, Denmark
| | - Nis Brix
- Department of Public Health, Research Unit for Epidemiology, Aarhus University, Bartholins Alle 2, 8000 Aarhus C, Denmark
- Department of Clinical Genetics, Aarhus University Hospital, 8200 Aarhus N, Denmark
| | - Lea Lykke Harrits Lunddorf
- Department of Public Health, Research Unit for Epidemiology, Aarhus University, Bartholins Alle 2, 8000 Aarhus C, Denmark
| | - Andreas Ernst
- Department of Public Health, Research Unit for Epidemiology, Aarhus University, Bartholins Alle 2, 8000 Aarhus C, Denmark
- Department of Urology, Aarhus University Hospital, 8200 Aarhus N, Denmark
| | - Birgit Bjerre Høyer
- Open Patient Data Explorative Network, Odense University Hospital, 5000 Odense, Denmark
| | - Gunnar Toft
- Steno Diabetes Center Aarhus, Aarhus University Hospital, 8200 Aarhus N, Denmark
| | - Tine Brink Henriksen
- Department of Clinical Medicine, Aarhus University, 8200 Aarhus N, Denmark
- Department of Paediatrics and Adolescent Medicine, Aarhus University Hospital, 8200 Aarhus N, Denmark
| | - Cecilia Høst Ramlau-Hansen
- Department of Public Health, Research Unit for Epidemiology, Aarhus University, Bartholins Alle 2, 8000 Aarhus C, Denmark
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8
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Gaml-Sørensen A, Brix N, Lunddorf LLH, Ernst A, Høyer BB, Olsen SF, Granström C, Toft G, Henriksen TB, Ramlau-Hansen CH. Maternal intake of folate and folic acid during pregnancy and pubertal timing in girls and boys: A population-based cohort study. Paediatr Perinat Epidemiol 2023; 37:618-629. [PMID: 37132131 DOI: 10.1111/ppe.12981] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/03/2022] [Revised: 04/11/2023] [Accepted: 04/14/2023] [Indexed: 05/04/2023]
Abstract
BACKGROUND Folate is essential for normal foetal development as it plays an important role for gene expression during different periods of foetal development. Thus, prenatal exposure to folate may have a programming effect on pubertal timing. OBJECTIVES To study the association between maternal intake of folate during pregnancy and pubertal timing in girls and boys. METHODS We studied 6585 girls and 6326 boys from a Danish population-based Puberty Cohort, 2000-2021. Information on maternal intake of folate from diet and folic acid from supplements was obtained from a food-frequency questionnaire in mid-pregnancy, and total folate was calculated as dietary folate equivalents. Information on age at menarche in girls, age at first ejaculation and voice break in boys, and Tanner stages, acne and axillary hair in both girls and boys was obtained every 6 months throughout puberty. We estimated mean monthly differences according to exposure groups for each pubertal milestone in addition to a combined estimate for the average age at attaining all pubertal milestones using multivariable interval-censored regression models. Total folate was analysed in quintiles, continuous and as restricted cubic splines. RESULTS Maternal intake of total folate in mid-pregnancy was not associated with pubertal timing in girls (combined estimate for overall pubertal timing per standard deviation (SD 325 μg/day) decrease in maternal intake of total folate: -0.14 months (95% confidence interval [CI] -0.51, 0.22)). Boys had slightly later overall pubertal timing per standard deviation (SD 325 μg/day) decrease in maternal intake of total folate (combined estimate: 0.40 months, 95% CI 0.01, 0.72). Spline plots supported these findings. CONCLUSIONS Prenatal exposure to low maternal intake of total folate in mid-pregnancy was not associated with pubertal timing in girls but associated with slightly later pubertal timing in boys. This minor delay is likely not of clinical importance.
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Affiliation(s)
| | - Nis Brix
- Department of Public Health, Aarhus University, Aarhus C, Denmark
- Department of Clinical Genetics, Aarhus University Hospital, Aarhus N, Denmark
| | | | - Andreas Ernst
- Department of Public Health, Aarhus University, Aarhus C, Denmark
- Department of Urology, Aarhus University Hospital, Aarhus N, Denmark
| | - Birgit Bjerre Høyer
- Open Patient Data Explorative Network, Odense University Hospital, Odense, Denmark
| | - Sjurdur Frodi Olsen
- Department of Epidemiology Research, Statens Serum Institut, Copenhagen S, Denmark
- Department of Public Health, University of Copenhagen, Copenhagen K, Denmark
| | - Charlotta Granström
- Department of Epidemiology Research, Statens Serum Institut, Copenhagen S, Denmark
| | - Gunnar Toft
- Steno Diabetes Center Aarhus, Aarhus University Hospital, Aarhus N, Denmark
| | - Tine Brink Henriksen
- Perinatal Epidemiology Research Unit, Department of Paediatrics and Adolescent Medicine, Aarhus University Hospital, Aarhus N, Denmark
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9
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Thomsen AH, Gaml-Sørensen A, Brix N, Tøttenborg SS, Hougaard KS, Ernst A, Arendt LH, Toft G, Bonde JP, Ramlau-Hansen CH. Maternal alcohol intake in early pregnancy and biomarkers of fecundity in adult sons: A cohort study. Reprod Toxicol 2023; 119:108396. [PMID: 37217037 DOI: 10.1016/j.reprotox.2023.108396] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Revised: 04/27/2023] [Accepted: 05/10/2023] [Indexed: 05/24/2023]
Abstract
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. Information on maternal weekly average alcohol intake (0 drinks [ref], >0-1 drinks, >1-3 drinks, >3 drinks) and binge drinking episodes (intake of ≥5 drinks on one occasion: (0 [ref], 1-2, ≥3 episodes)) was self-reported at around gestational week 17. Outcomes included semen characteristics, testes volume and reproductive hormones. We found some small tendencies towards lower semen characteristics and an altered hormone level profile in sons of mother who had an intake of > 3 drinks/week in early pregnancy and sons of mother who had ≥ 3 episodes of binge drinking in pregnancy. However, the effect estimates were overall small and inconsistent and with no indication of a dose dependent association. Due to the limited number of mothers with a high weekly alcohol intake, we cannot exclude whether prenatal exposure to higher doses than 4.5 drinks/week of alcohol in early pregnancy might have a detrimental effect on the biomarkers of fecundity in adult sons..
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Affiliation(s)
- Anne Hjorth Thomsen
- Department of Public Health, Research Unit for Epidemiology, Aarhus University, Aarhus, Denmark.
| | - Anne Gaml-Sørensen
- Department of Public Health, Research Unit for Epidemiology, Aarhus University, Aarhus, Denmark
| | - Nis Brix
- Department of Public Health, Research Unit for Epidemiology, Aarhus University, Aarhus, Denmark; Department of Clinical Genetics, Aarhus University Hospital, Aarhus, Denmark
| | - Sandra Søgaard Tøttenborg
- Department of Occupational and Environmental Medicine, Bispebjerg and Frederiksberg Hospital, Copenhagen University Hospital, Copenhagen, Denmark; Department of Public Health, University of Copenhagen, Copenhagen, Denmark
| | - Karin Sørig Hougaard
- Department of Public Health, University of Copenhagen, Copenhagen, Denmark; National Research Centre for Working Environment, Copenhagen, Denmark
| | - Andreas Ernst
- Department of Public Health, Research Unit for Epidemiology, Aarhus University, Aarhus, Denmark; Department of Urology, Aarhus University Hospital, Aarhus, Denmark
| | - Linn Håkonsen Arendt
- Department of Public Health, Research Unit for Epidemiology, Aarhus University, Aarhus, Denmark; Department of Obstetrics and Gynecology, Aarhus University Hospital, Aarhus, Denmark
| | - Gunnar Toft
- Steno Diabetes Center Aarhus, Aarhus University Hospital, Aarhus, Denmark
| | - Jens Peter Bonde
- Department of Occupational and Environmental Medicine, Bispebjerg and Frederiksberg Hospital, Copenhagen University Hospital, Copenhagen, Denmark; Department of Public Health, University of Copenhagen, Copenhagen, Denmark
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10
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Gaml-Sørensen A, Brix N, Hærvig KK, Lindh C, Tøttenborg SS, Hougaard KS, Høyer BB, Ernst A, Arendt LH, Clemmensen PJ, Bonde JPE, Henriksen TB, Toft G, Arah OA, Ramlau-Hansen CH. Maternal vitamin D levels and male reproductive health: a population-based follow-up study. Eur J Epidemiol 2023; 38:469-484. [PMID: 36952117 PMCID: PMC10976978 DOI: 10.1007/s10654-023-00987-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2022] [Accepted: 03/05/2023] [Indexed: 03/24/2023]
Abstract
Maternal vitamin D levels during pregnancy may be important for reproductive health in male offspring by regulating cell proliferation and differentiation during development. We conducted a follow-up study of 827 young men from the Fetal Programming of Semen Quality (FEPOS) cohort, nested in the Danish National Birth Cohort to investigate if maternal vitamin D levels were associated with measures of reproductive health in adult sons. These included semen characteristics, testes volume, and reproductive hormone levels and were analysed according to maternal vitamin D (25(OH)D3) levels during pregnancy. In addition, an instrumental variable analysis using seasonality in sun exposure as an instrument for maternal vitamin D levels was conducted. We found that sons of mothers with vitamin D levels < 25 nmol/L had 11% (95% CI - 19 to - 2) lower testes volume and a 1.4 (95% CI 1.0 to 1.9) times higher risk of having low testes volume (< 15 mL), in addition to 20% (95% CI - 40 to 9) lower total sperm count and a 1.6 (95% CI 0.9 to 2.9) times higher risk of having a low total sperm count (< 39 million) compared with sons of mothers with vitamin D levels > 75 nmol/L. Continuous models, spline plots and an instrumental variable analysis supported these findings. Low maternal vitamin D levels were associated with lower testes volume and lower total sperm count with indications of dose-dependency. Maternal vitamin D level above 75 nmol/L during pregnancy may be beneficial for testes function in adult sons.
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Affiliation(s)
- Anne Gaml-Sørensen
- Department of Public Health, Research Unit for Epidemiology, Aarhus University, Bartholins Allé 2, 8000, Aarhus C, Denmark.
- Department of Epidemiology, Fielding School of Public Health, University of California, Los Angeles (UCLA), Los Angeles, CA, 90095, USA.
| | - Nis Brix
- Department of Public Health, Research Unit for Epidemiology, Aarhus University, Bartholins Allé 2, 8000, Aarhus C, Denmark
- Department of Clinical Genetics, Aarhus University Hospital, 8200, Aarhus N, Denmark
| | - Katia Keglberg Hærvig
- Department of Occupational and Environmental Medicine, Bispebjerg and Frederiksberg Hospital, Copenhagen University Hospital, 2400, Copenhagen NV, Denmark
| | - Christian Lindh
- Division of Occupational and Environmental Medicine, Lund University, 22363, Lund, Sweden
| | - Sandra Søgaard Tøttenborg
- Department of Occupational and Environmental Medicine, Bispebjerg and Frederiksberg Hospital, Copenhagen University Hospital, 2400, Copenhagen NV, Denmark
- Department of Public Health, University of Copenhagen, 1014, Copenhagen K, Denmark
| | - Karin Sørig Hougaard
- Department of Public Health, University of Copenhagen, 1014, Copenhagen K, Denmark
- National Research Centre for the Working Environment, 2100, Copenhagen Ø, Denmark
| | - Birgit Bjerre Høyer
- Department of Public Health, Research Unit for Epidemiology, Aarhus University, Bartholins Allé 2, 8000, Aarhus C, Denmark
- Department of Regional Development, Region of Southern Denmark, 7100, Vejle, Denmark
| | - Andreas Ernst
- Department of Public Health, Research Unit for Epidemiology, Aarhus University, Bartholins Allé 2, 8000, Aarhus C, Denmark
- Department of Urology, Aarhus University Hospital, 8200, Aarhus N, Denmark
| | - Linn Håkonsen Arendt
- Department of Public Health, Research Unit for Epidemiology, Aarhus University, Bartholins Allé 2, 8000, Aarhus C, Denmark
- Department of Obstetrics and Gynaecology, Aarhus University Hospital, 8200, Aarhus N, Denmark
| | - Pernille Jul Clemmensen
- Department of Public Health, Research Unit for Epidemiology, Aarhus University, Bartholins Allé 2, 8000, Aarhus C, Denmark
| | - Jens Peter Ellekilde Bonde
- Department of Occupational and Environmental Medicine, Bispebjerg and Frederiksberg Hospital, Copenhagen University Hospital, 2400, Copenhagen NV, Denmark
- Department of Public Health, University of Copenhagen, 1014, Copenhagen K, Denmark
| | - Tine Brink Henriksen
- Perinatal Epidemiology Research Unit, Aarhus University, Aarhus C, Denmark
- Department of Paediatrics and Adolescent Medicine, Aarhus University Hospital, 8200, Aarhus N, Denmark
| | - Gunnar Toft
- Steno Diabetes Center Aarhus, Aarhus University Hospital, 8200, Aarhus N, Denmark
| | - Onyebuchi A Arah
- Department of Public Health, Research Unit for Epidemiology, Aarhus University, Bartholins Allé 2, 8000, Aarhus C, Denmark
- Department of Epidemiology, Fielding School of Public Health, University of California, Los Angeles (UCLA), Los Angeles, CA, 90095, USA
- Department of Statistics, Division of Physical Sciences, UCLA College, Los Angeles, CA, 90024, USA
| | - Cecilia Høst Ramlau-Hansen
- Department of Public Health, Research Unit for Epidemiology, Aarhus University, Bartholins Allé 2, 8000, Aarhus C, Denmark
- Department of Epidemiology, Fielding School of Public Health, University of California, Los Angeles (UCLA), Los Angeles, CA, 90095, USA
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11
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Gaml-Sørensen A, Brix N, Tøttenborg SS, Hougaard KS, Hærvig KK, Bonde JPE, Henriksen TB, Toft G, Ramlau-Hansen CH. Selection bias in a male-offspring cohort investigating fecundity: is there reason for concern? Hum Reprod 2023; 38:293-305. [PMID: 36370427 DOI: 10.1093/humrep/deac241] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2022] [Revised: 10/05/2022] [Indexed: 11/13/2022] Open
Abstract
STUDY QUESTION Is there risk of selection bias in etiological studies investigating prenatal risk factors of poor male fecundity in a cohort of young men? SUMMARY ANSWER The risk of selection bias is considered limited despite a low participation rate. WHAT IS KNOWN ALREADY Participation rates in studies relying on volunteers to provide a semen sample are often very low. Many risk factors for poor male fecundity are associated with participation status, and as men with low fecundity may be more inclined to participate in studies of semen quality, a risk of selection bias exists. STUDY DESIGN, SIZE, DURATION A population-based follow-up study of 5697 young men invited to the Fetal Programming of Semen Quality (FEPOS) cohort nested within the Danish National Birth Cohort (DNBC), 1998-2019. PARTICIPANTS/MATERIALS, SETTING, METHODS Young men (age range: 18 years, 9 months to 21 years, 4 months) born 1998-2000 by mothers included in the DNBC were invited to participate in FEPOS. In total, 1173 men answered a survey in FEPOS (n = 115 participated partly); of those, 1058 men participated fully by also providing a semen and a blood sample at a clinical visit. Differential selection according to parental baseline characteristics in the first trimester, the sons' own characteristics from the FEPOS survey, and urogenital malformations and diseases in reproductive organs from the Danish registers were investigated using logistic regression. The influence of inverse probability of selection weights (IPSWs) to investigate potential selection bias was examined using a predefined exposure-outcome association of maternal smoking in the first trimester (yes, no) and total sperm count analysed using adjusted negative binomial regression. A multidimensional bias analysis on the same association was performed using a variety of bias parameters to assess different scenarios of differential selection. MAIN RESULTS AND THE ROLE OF CHANCE Participation differed according to most parental characteristics in first trimester but did not differ according to the prevalence of a urogenital malformation or disease in the reproductive organs. Associations between maternal smoking in the first trimester and male fecundity were similar when the regression models were fitted without and with IPSWs. Adjusting for other potential risk factors for poor male fecundity, maternal smoking was associated with 21% (95% CI: -32% to -9%) lower total sperm count. In the bias analysis, this estimate changed only slightly under realistic scenarios. This may be extrapolated to other exposure-outcome associations. LIMITATIONS, REASONS FOR CAUTION We were unable to directly assess markers of male fecundity for non-participants from, for example an external source and therefore relied on potential proxies of fecundity. We did not have sufficient power to analyse associations between prenatal exposures and urogenital malformations. WIDER IMPLICATIONS OF THE FINDINGS The results are reassuring when using this cohort to identify causes of poor male fecundity. The results may be generalized to other similar cohorts. As the young men grow older, they can be followed in the Danish registers, as an external source, to examine, whether participation is associated with the risk of having an infertility diagnosis. STUDY FUNDING/COMPETING INTEREST(S) The project was funded by the Lundbeck Foundation (R170-2014-855), the Capital Region of Denmark, Medical doctor Sofus Carl Emil Friis and spouse Olga Doris Friis's Grant, Axel Muusfeldt's Foundation (2016-491), AP Møller Foundation (16-37), the Health Foundation, Dagmar Marshall's Fond, Aarhus University and Independent Research Fund Denmark (9039-00128B). The authors declare that they have no conflict of interest. TRIAL REGISTRATION NUMBER N/A.
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Affiliation(s)
- Anne Gaml-Sørensen
- Department of Public Health, Research Unit for Epidemiology, Aarhus University, Aarhus C, Denmark
| | - Nis Brix
- Department of Public Health, Research Unit for Epidemiology, Aarhus University, Aarhus C, Denmark
- Department of Clinical Genetics, Aarhus University Hospital, Aarhus N, Denmark
| | - Sandra Søgaard Tøttenborg
- Department of Occupational and Environmental Medicine, Bispebjerg and Frederiksberg Hospital, University of Copenhagen, Copenhagen NV, Denmark
- Department of Public Health, University of Copenhagen, København K, Denmark
| | - Karin Sørig Hougaard
- Department of Public Health, University of Copenhagen, København K, Denmark
- National Research Centre for the Working Environment, Copenhagen Ø, Denmark
| | - Katia Keglberg Hærvig
- Department of Occupational and Environmental Medicine, Bispebjerg and Frederiksberg Hospital, University of Copenhagen, Copenhagen NV, Denmark
| | - Jens Peter Ellekilde Bonde
- Department of Occupational and Environmental Medicine, Bispebjerg and Frederiksberg Hospital, University of Copenhagen, Copenhagen NV, Denmark
- Department of Public Health, University of Copenhagen, København K, Denmark
| | - Tine Brink Henriksen
- Perinatal Epidemiology Research Unit, Aarhus University, Aarhus N, Denmark
- Department of Paediatrics and Adolescent Medicine, Aarhus University Hospital, Aarhus N, Denmark
| | - Gunnar Toft
- Steno Diabetes Center Aarhus, Aarhus University Hospital, Aarhus N, Denmark
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12
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Langergaard MJ, Ernst A, Brix N, Gaml-Sørensen A, Tøttenborg SS, Bonde JPE, Toft G, Hougaard KS, Ramlau-Hansen CH. Maternal age at menarche and reproductive health in young adult men: a cohort study. Hum Reprod 2023; 38:125-138. [PMID: 36303450 DOI: 10.1093/humrep/deac231] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2022] [Revised: 09/27/2022] [Indexed: 01/11/2023] Open
Abstract
STUDY QUESTION Is maternal age at menarche associated with reproductive health in sons measured by semen quality, testes volume and reproductive hormone levels? SUMMARY ANSWER Later maternal age at menarche was associated with impaired semen characteristics, lower testes volume and altered levels of reproductive hormones, while earlier maternal age at menarche was not strongly associated with reproductive outcomes in sons. WHAT IS KNOWN ALREADY Both earlier and later maternal age at menarche may be associated with altered male reproductive health outcomes. This is the first study to investigate the potential association between maternal age at menarche and semen quality, testes volume and reproductive hormone levels in sons. STUDY DESIGN, SIZE, DURATION In this population-based cohort study, we used data from the Fetal Programming of Semen Quality Cohort nested within the Danish National Birth Cohort. In total, 5697 sons born in 1998-2000 were invited to participate in the cohort in 2017-2019. PARTICIPANTS/MATERIALS, SETTING, METHODS In total, 1043 (18% of the invited) young men with information on maternal age at menarche provided a semen and blood sample, measured their testes volume, and filled in a questionnaire on health behavior and pubertal development. Maternal age at menarche was reported by the mothers during pregnancy and examined categorically (as earlier, at the same time or later than their peers), continuously and modeled as splines. We estimated relative percentage differences in the reproductive outcomes using negative binomial regression models. Further, we did a mediation analysis to investigate the potential mediating role of timing of the sons' pubertal development. MAIN RESULTS AND THE ROLE OF CHANCE Sons whose mothers had age at menarche later than peers had 15% lower (95% CI: -27%; 0%) sperm concentration, 14% lower (95% CI: -28%; 1%) total sperm count, 7% higher (95% CI: 0%; 14%) proportion of nonprogressive or immotile spermatozoa, 6% lower (95% CI: -11%; 0%) testes volume, 6% lower (95% CI: -12%; 1%) luteinizing hormone, 6% lower (95% CI: -12%; 1%) sex hormone-binding globulin and 5% lower (95% CI: -9%; 0%) testosterone levels compared with sons whose mothers had age at menarche at the same time as peers. Our study did not suggest that earlier maternal age at menarche was strongly associated with semen quality, testes volume or reproductive hormones in sons. However, the spline analyses indicated a potential inverted U-shaped association for sperm concentration and testes volume, and levels of sex hormone-binding globulin and testosterone. We found no strong evidence of mediation by timing of the sons' own pubertal development. LIMITATIONS, REASONS FOR CAUTION There was a rather low participation rate in the Fetal Programming of Semen Quality Cohort and we tried to counter it by applying selection weights. Maternal age at menarche was recalled during pregnancy, which may introduce misclassification, most likely nondifferential. Inaccuracy of the sons' recalled pubertal development years after the event may result in underestimation of the possible mediating role of pubertal timing. WIDER IMPLICATIONS OF THE FINDINGS Our findings may represent a degree of shared heritability of reproductive health or be a result of an underlying epigenetic profile or unknown shared environmental, cultural or dietary exposure, causing both altered age at menarche and impaired reproductive health outcomes in sons. However, the exact mechanism for the investigated association remains unknown. STUDY FUNDING/COMPETING INTEREST(S) This article is part of the ReproUnion collaborative study, cofinanced by the European Union, Intereg V ÖKS (20200407). The FEPOS project was further funded by the Lundbeck Foundation (R170-2014-855), the Capital Region of Denmark, Medical doctor Sofus Carl Emil Friis and spouse Olga Doris Friis's Grant, Axel Muusfeldt's Foundation (2016-491), A.P. Møller Foundation (16-37), the Health Foundation and Dagmar Marshall's Fond. Additionally, this study received funding from Aarhus University. There are no competing interests. TRIAL REGISTRATION NUMBER N/A.
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Affiliation(s)
| | - Andreas Ernst
- Department of Public Health, Research Unit for Epidemiology, Aarhus University, Aarhus C, Denmark
- Department of Urology, Aarhus University Hospital, Aarhus N, Denmark
| | - Nis Brix
- Department of Public Health, Research Unit for Epidemiology, Aarhus University, Aarhus C, Denmark
- Department of Clinical Genetics, Aarhus University Hospital, Aarhus N, Denmark
| | - Anne Gaml-Sørensen
- Department of Public Health, Research Unit for Epidemiology, Aarhus University, Aarhus C, Denmark
| | - Sandra S Tøttenborg
- Department of Occupational and Environmental Medicine, Copenhagen University Hospital - Bispebjerg and Frederiksberg Hospital, Copenhagen NV, Denmark
- Department of Public Health, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen K, Denmark
| | - Jens Peter E Bonde
- Department of Occupational and Environmental Medicine, Copenhagen University Hospital - Bispebjerg and Frederiksberg Hospital, Copenhagen NV, Denmark
- Department of Public Health, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen K, Denmark
| | - Gunnar Toft
- Steno Diabetes Center Aarhus, Aarhus University Hospital, Aarhus N, Denmark
| | - Karin S Hougaard
- Department of Public Health, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen K, Denmark
- National Research Centre for the Working Environment, Copenhagen East, Denmark
| | - Cecilia H Ramlau-Hansen
- Department of Public Health, Research Unit for Epidemiology, Aarhus University, Aarhus C, Denmark
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Clemmensen PJ, Brix N, Schullehner J, Gaml-Sørensen A, Toft G, Tøttenborg SS, Ebdrup NH, Hougaard KS, Hansen B, Sigsgaard T, Kolstad HA, Bonde JPE, Ramlau-Hansen CH. Nitrate in Maternal Drinking Water during Pregnancy and Measures of Male Fecundity in Adult Sons. Int J Environ Res Public Health 2022; 19:14428. [PMID: 36361307 PMCID: PMC9656746 DOI: 10.3390/ijerph192114428] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/29/2022] [Revised: 10/26/2022] [Accepted: 10/28/2022] [Indexed: 06/16/2023]
Abstract
Animal studies indicate deleterious effects of nitrate exposure on fecundity, but effects in humans are unknown, both for the prenatal and postnatal periods. We aimed to investigate if exposure to nitrate in maternal drinking water during the sensitive period of fetal life is associated with measures of fecundity in the adult sons. In a sub-analysis, the potential effects of nitrate exposure in adulthood were investigated. This cohort included 985 young adult men enrolled in The Fetal Programming of Semen Quality Cohort (FEPOS). Semen characteristics, testes volume and reproductive hormones were analyzed in relation to nitrate concentration in maternal drinking water, using a negative binomial regression model. The nitrate concentration in drinking water was obtained from monitoring data from Danish waterworks that were linked with the mothers' residential address during pregnancy. The median nitrate concentration in maternal drinking water was 2 mg/L. At these low exposure levels, which are far below the World Health Organization's (WHO) guideline value of 50 mg/L, we did not find indications of harmful effects of nitrate on the investigated measures of male fecundity.
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Affiliation(s)
| | - Nis Brix
- Department of Public Health, Aarhus University, 8000 Aarhus, Denmark
- Department of Clinical Genetics, Aarhus University Hospital, 8200 Aarhus, Denmark
| | - Jörg Schullehner
- Department of Public Health, Aarhus University, 8000 Aarhus, Denmark
- Geological Survey of Denmark and Greenland, 8000 Aarhus, Denmark
- Danish Big Data Centre for Environment and Health (BERTHA), Aarhus University, 8000 Aarhus, Denmark
| | | | - Gunnar Toft
- Steno Diabetes Center Aarhus, Aarhus University Hospital, 8200 Aarhus, Denmark
| | - Sandra Søgaard Tøttenborg
- Department of Occupational and Environmental Medicine, Copenhagen University Hospital—Bispebjerg and Frederiksberg Hospital, 2400 Copenhagen, Denmark
- Department of Public Health, University of Copenhagen, 1014 Copenhagen, Denmark
| | | | - Karin Sørig Hougaard
- Department of Public Health, University of Copenhagen, 1014 Copenhagen, Denmark
- National Research Centre for the Working Environment, 2100 Copenhagen, Denmark
| | - Birgitte Hansen
- Geological Survey of Denmark and Greenland, 8000 Aarhus, Denmark
| | - Torben Sigsgaard
- Department of Public Health, Aarhus University, 8000 Aarhus, Denmark
- Danish Big Data Centre for Environment and Health (BERTHA), Aarhus University, 8000 Aarhus, Denmark
- Centre for Integrated Register-Based Research, Aarhus University (CIRRAU), 8000 Aarhus, Denmark
| | - Henrik Albert Kolstad
- Department of Occupational Medicine, Aarhus University Hospital, 8200 Aarhus, Denmark
- Department of Clinical Medicine, Aarhus University, 8200 Aarhus, Denmark
| | - Jens Peter Ellekilde Bonde
- Department of Occupational and Environmental Medicine, Copenhagen University Hospital—Bispebjerg and Frederiksberg Hospital, 2400 Copenhagen, Denmark
- Department of Public Health, University of Copenhagen, 1014 Copenhagen, Denmark
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14
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Thomsen AH, Gaml-Sørensen A, Brix N, Ernst A, Lunddorf LLH, Strandberg-Larsen K, Højgaard A, Ramlau-Hansen CH. Gender incongruence and timing of puberty: a population-based cohort study. Fertil Steril 2022; 118:938-945. [PMID: 36163086 DOI: 10.1016/j.fertnstert.2022.07.018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2022] [Revised: 07/16/2022] [Accepted: 07/19/2022] [Indexed: 01/13/2023]
Abstract
OBJECTIVE To study whether the timing of puberty in adolescents who reported gender incongruence (incongruence between birth-assigned sex and self-identified gender) was different from those adolescents who reported gender congruence. DESIGN Population-based cohort study using data from the Danish National Birth Cohort. SETTING Not applicable. PATIENT(S) Birth-assigned boys and girls born between 2000 and 2003, who self-reported gender incongruence at 11 years (N = 10,046) and their pubertal developmental stages from age 11 years to every 6 months throughout puberty were included. INTERVENTION(S) Not applicable. MAIN OUTCOME MEASURE Mean age differences in months at reaching Tanner stages 2-5 for breast or genital development and pubic hair, voice break, first ejaculation, menarche, axillary hair, acne, and the average difference at attaining all pubertal milestones (primary outcome). RESULT(S) In total, 549 (5.5% ) adolescents reported part or full gender incongruence at 11 years. Tendencies toward earlier timing of puberty were observed in adolescents who reported part gender incongruence (average difference, birth-assigned boys: -3.2 months [95% confidence interval {CI}: -6.7; 0.3]; birth-assigned girls: -2.0 months [95% CI: -3.9; -0.1]). Tendencies toward earlier timing of puberty were observed in adolescents who reported full gender incongruence (average difference, birth-assigned boys: -2.4 months [95% CI: -5.0; 0.4]; birth-assigned girls: -1.9 months [95% CI: -5.1; 1.2]). CONCLUSIONS The results from this study indicated that birth-assigned boys and girls who reported either part or full gender incongruence tended to reach puberty slightly earlier than those adolescents who reported gender congruence at 11 years of age. Knowledge on the timing of puberty among adolescents who experience gender incongruence is essential to inform mutual decision-making in clinical settings.
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Affiliation(s)
- Anne H Thomsen
- Department of Public Health, Research Unit for Epidemiology, Aarhus University, Aarhus, Denmark.
| | - Anne Gaml-Sørensen
- Department of Public Health, Research Unit for Epidemiology, Aarhus University, Aarhus, Denmark
| | - Nis Brix
- Department of Public Health, Research Unit for Epidemiology, Aarhus University, Aarhus, Denmark; Department of Clinical Genetics, Aarhus University Hospital, Aarhus, Denmark
| | - Andreas Ernst
- Department of Public Health, Research Unit for Epidemiology, Aarhus University, Aarhus, Denmark; Department of Urology, Aarhus University Hospital, Aarhus, Denmark
| | - Lea L H Lunddorf
- Department of Public Health, Research Unit for Epidemiology, Aarhus University, Aarhus, Denmark
| | | | - Astrid Højgaard
- Sexological Centre, Aalborg University Hospital, Aalborg, Denmark
| | - Cecilia H Ramlau-Hansen
- Department of Public Health, Research Unit for Epidemiology, Aarhus University, Aarhus, Denmark
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Arendt LH, Gaml-Sørensen A, Ernst A, Brix N, Toft G, Tøttenborg SS, Hougaard KS, Bonde JPE, Ramlau-Hansen CH. Semen quality and reproductive hormones in sons of subfertile couples: a cohort study. Fertil Steril 2022; 118:671-678. [PMID: 35985861 DOI: 10.1016/j.fertnstert.2022.06.035] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2021] [Revised: 06/28/2022] [Accepted: 06/30/2022] [Indexed: 01/13/2023]
Abstract
OBJECTIVE To study the associations between parental subfecundity, assessed by time to pregnancy and use of medically-assisted reproduction, and reproductive health of young men. DESIGN Cohort study. SETTING Denmark. PATIENT(S) A total of 1,058 men in the Fetal Programming of Semen quality cohort, a subcohort of the Danish National Birth Cohort. INTERVENTION(S) From 2017-2019, men were recruited and provided semen and blood samples. Information on parental time to pregnancy and use of medically-assisted reproduction (including type of treatment) as well as demographic, health, and lifestyle factors were available. We estimated the crude and adjusted relative percentage differences with 95% confidence intervals (CIs) in the outcomes according to time to pregnancy and use of medically-assisted reproduction, using multiple adjusted negative binomial regression analysis. MAIN OUTCOME MEASURE(S) Semen characteristics (semen volume, sperm concentration, total sperm count, sperm motility, and morphology), testicular volume, and reproductive hormone levels (follicle stimulating hormone, luteinizing hormone, testosterone, estradiol, sex hormone-binding globulin, and free androgen index). RESULT(S) Overall, semen quality and levels of reproductive hormones were not lower among sons of subfecund parents reporting a time to pregnancy >6 months or use of intrauterine insemination. Sons conceived after in vitro fertilization or intracytoplasmic sperm injection, had a higher semen concentration (29%; 95% CI, -7%-79%) and a higher percentage of sperm with normal morphology (20%; 95% CI, -8%-56%), but with 95% CI overlapping the null. Moreover, these sons had slightly higher estradiol levels (30%; 95% CI, 7%-57%). The absolute differences seen were small, and the clinical significance of these differences are unknown. CONCLUSION(S) We found no major difference in semen quality or reproductive hormones in sons conceived by subfertile couples or with the use of medically-assisted reproduction.
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Affiliation(s)
- Linn H Arendt
- Department of Public Health, Research Unit for Epidemiology, Aarhus University, Aarhus, Denmark; Department of Obstetrics and Gynaecology, Horsens Regional Hospital, Horsens Denmark.
| | - Anne Gaml-Sørensen
- Department of Public Health, Research Unit for Epidemiology, Aarhus University, Aarhus, Denmark
| | - Andreas Ernst
- Department of Public Health, Research Unit for Epidemiology, Aarhus University, Aarhus, Denmark; Department of Urology, Aarhus University Hospital, Aarhus, Denmark
| | - Nis Brix
- Department of Public Health, Research Unit for Epidemiology, Aarhus University, Aarhus, Denmark; Department of Clinical Genetics, Aarhus University Hospital, Aarhus, Denmark
| | - Gunnar Toft
- Department of Clinical Epidemiology, Aarhus University, Aarhus, Denmark; Steno Diabetes Center Aarhus, Aarhus University Hospital, Aarhus N, Denmark
| | - Sandra S Tøttenborg
- Department of Occupational and Environmental Medicine, Bispebjerg and Frederiksberg Hospital, University of Copenhagen, Denmark; Department of Public Health, University of Copenhagen, Copenhagen, Denmark
| | - Karin S Hougaard
- Department of Public Health, University of Copenhagen, Copenhagen, Denmark; National Research Center for the Working Environment, Copenhagen, Denmark
| | - Jens Peter E Bonde
- Department of Occupational and Environmental Medicine, Bispebjerg and Frederiksberg Hospital, University of Copenhagen, Denmark; Department of Public Health, University of Copenhagen, Copenhagen, Denmark
| | - Cecilia H Ramlau-Hansen
- Department of Public Health, Research Unit for Epidemiology, Aarhus University, Aarhus, Denmark
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Udholm LF, Gaml-Sørensen A, Arendt LH, Brix N, Lunddorf LL, Ernst A, Knudsen UB, Hjortdal VE, Ramlau-Hansen CH. Timing of pubertal development in boys and girls with congenital heart defects: a nationwide cohort study. International Journal of Cardiology Congenital Heart Disease 2022. [DOI: 10.1016/j.ijcchd.2022.100351] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
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17
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Gaml-Sørensen A, Brix N, Toft G, Henriksen TB, Ernst A, Arendt LH, Tøttenborg SS, Hærvig KK, Hougaard KS, Bonde JPE, Ramlau-Hansen CH. Parental Separation and Semen Quality in Young Men: A Population-Based Cohort Study. Clin Epidemiol 2022; 14:127-140. [PMID: 35115841 PMCID: PMC8801330 DOI: 10.2147/clep.s348763] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2021] [Accepted: 12/27/2021] [Indexed: 01/15/2023] Open
Abstract
Purpose Parental separation may be a stressful life event with the potential to influence hormonal regulation of offspring reproductive health and thereby affect semen quality in young men. We aimed to study the association between parental separation in pregnancy or in childhood and semen quality in young men and to study whether the timing of parental separation in childhood was important. Patients and Methods We conducted a follow-up study of 1058 young men born 1998–2000 from the Fetal Programming of Semen Quality (FEPOS) cohort nested within the Danish National Birth Cohort. Data on parental separation were obtained longitudinal by self-report. Parental separation in pregnancy was dichotomized, and parental separation in childhood was both dichotomized and categorized according to the timing of parental separation (from birth, from early childhood (0–5 years), and from late childhood (6–10 years)). Semen volume, concentration, total sperm count, motility, morphology, and testes volume were analysed using multivariable negative binomial regression models. Results Parental separation in pregnancy was not associated with semen quality. The association between parental separation in childhood and semen quality differed with the timing of parental separation. Parental separation from birth was associated with higher semen volume of 25%, 95% CI (−5; 64); higher total sperm count of 62%, 95% CI (−6; 179); and higher proportion of morphologically normal spermatozoa of 59%, 95% CI (20; 111). Parental separation in early childhood was associated with lower semen volume of −14%, 95% CI (−24; −3); lower concentration of −15%, 95% CI (−28; 1); lower total sperm count of −17%, 95% CI (−32; 2) and lower testes volume of −11%, 95% CI (−18; −3). Conclusion The timing of parental separation was important, and parental separation from birth was associated with higher semen quality, and parental separation in early childhood was associated with lower semen quality.
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Affiliation(s)
- Anne Gaml-Sørensen
- Department of Public Health, Research Unit for Epidemiology, Bartholins Allé 2, Aarhus University, Aarhus C, 8000, Denmark
- Correspondence: Anne Gaml-Sørensen, Department of Public Health, Research Unit for Epidemiology, Bartholins Allé 2, Aarhus University, Aarhus C, 8000, Denmark, Tel +45 40868183 Email
| | - Nis Brix
- Department of Public Health, Research Unit for Epidemiology, Bartholins Allé 2, Aarhus University, Aarhus C, 8000, Denmark
- Department of Clinical Genetics, Aarhus University Hospital, Aarhus N, 8200, Denmark
| | - Gunnar Toft
- Department of Clinical Epidemiology, Aarhus University, Aarhus N, 8200, Denmark
- Steno Diabetes Center Aarhus, Aarhus University Hospital, Aarhus N, 8200, Denmark
| | - Tine Brink Henriksen
- Perinatal Epidemiology Research Unit, Department of Paediatrics and Adolescent Medicine, Aarhus University Hospital, Aarhus N, 8200, Denmark
| | - Andreas Ernst
- Department of Public Health, Research Unit for Epidemiology, Bartholins Allé 2, Aarhus University, Aarhus C, 8000, Denmark
- Department of Urology, Aarhus University Hospital, Aarhus N, 8200, Denmark
| | - Linn Håkonsen Arendt
- Department of Public Health, Research Unit for Epidemiology, Bartholins Allé 2, Aarhus University, Aarhus C, 8000, Denmark
- Department of Obstetrics and Gynecology, Aarhus University Hospital, Aarhus N, 8200, Denmark
| | - Sandra Søgaard Tøttenborg
- Department of Occupational and Environmental Medicine, Bispebjerg and Frederiksberg Hospital, Copenhagen NV, 2400, Denmark
| | - Katia Keglberg Hærvig
- Department of Occupational and Environmental Medicine, Bispebjerg and Frederiksberg Hospital, Copenhagen NV, 2400, Denmark
- Department of Public Health, University of Copenhagen, København K, 1014, Denmark
| | - Karin Sørig Hougaard
- Department of Public Health, University of Copenhagen, København K, 1014, Denmark
- National Research Centre for the Working Environment, Copenhagen East, 2100, Denmark
| | - Jens Peter Ellekilde Bonde
- Department of Occupational and Environmental Medicine, Bispebjerg and Frederiksberg Hospital, Copenhagen NV, 2400, Denmark
- Department of Public Health, University of Copenhagen, København K, 1014, Denmark
| | - Cecilia Høst Ramlau-Hansen
- Department of Public Health, Research Unit for Epidemiology, Bartholins Allé 2, Aarhus University, Aarhus C, 8000, Denmark
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Huang K, Gaml-Sørensen A, Lunddorf LLH, Ernst A, Brix N, Olsen J, Ramlau-Hansen CH. Caesarean delivery and pubertal timing in boys and girls: A Danish population-based cohort study. Paediatr Perinat Epidemiol 2022; 36:104-112. [PMID: 34825716 DOI: 10.1111/ppe.12827] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/12/2021] [Revised: 09/17/2021] [Accepted: 09/23/2021] [Indexed: 12/21/2022]
Abstract
BACKGROUND There is considerable public and scientific interest in the declining age of pubertal timing. Prenatal and postnatal stress has been proposed to relate with earlier pubertal timing, but it remains unknown whether intrapartum stress may affect pubertal timing as well. OBJECTIVE This study aims to examine the potential effect of caesarean delivery on pubertal timing in boys and girls. METHODS This study was based upon the nationwide Puberty Cohort nested within the Danish National Birth Cohort (DNBC) from 2000 to 2003. A total of 15,731 mother-child pairs with complete information on delivery mode and puberty were included in the main analysis. The delivery mode was categorised into non-instrumental vaginal delivery (reference), instrumental vaginal delivery, elective caesarean delivery before labour, emergency caesarean delivery during labour and un-specified caesarean delivery. Children's pubertal development were self-reported in web-based questionnaires from 11 years of age and every 6 months throughout puberty (2012-2019), including Tanner stages 2-5, menarche, voice break, first ejaculation, axillary hair growth and the onset of acne. Regression models for censored, normally distributed time-to-event data were used to estimate mean monthly differences in age at attaining the different pubertal milestones and the average of all these estimates for each sex (a combined indicator of pubertal timing). RESULTS A total of 2810 participants were born by caesarean delivery (17.9%). Neither elective nor emergency caesarean delivery was associated with earlier age at achieving the pubertal milestones in boys or in girls. For the combined indicator, the mean age differences for elective caesarean delivery and emergency caesarean delivery were 0.1 (95% CI -1.1, 1.4) months and -0.7 (95% CI -2.0, 0.5) months in boys and 0.7 (95% CI -0.7, 2.0) and 0.2 (95% CI -1.3, 1.7) in girls. CONCLUSIONS This study does not suggest a clinically important effect of caesarean delivery on children's pubertal timing.
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Affiliation(s)
- Kun Huang
- Department of Maternal, Child and Adolescent Health, Scientific Research Center in Preventive Medicine, MOE Key Laboratory of Population Health Across Life Cycle, NHC Key Laboratory of Study on Abnormal Gametes and Reproductive Tract, Anhui Provincial Key Laboratory of Population Health and Aristogenics, School of Public Health, Anhui Medical University, Hefei, China.,Research Unit for Epidemiology, Department of Public Health, Aarhus University, Aarhus C, Denmark
| | - Anne Gaml-Sørensen
- Research Unit for Epidemiology, Department of Public Health, Aarhus University, Aarhus C, Denmark
| | | | - Andreas Ernst
- Research Unit for Epidemiology, Department of Public Health, Aarhus University, Aarhus C, Denmark.,Department of Urology, Aarhus University Hospital, Aarhus N, Denmark
| | - Nis Brix
- Research Unit for Epidemiology, Department of Public Health, Aarhus University, Aarhus C, Denmark.,Department of Clinical Genetics, Aarhus University Hospital, Aarhus N, Denmark
| | - Jørn Olsen
- Research Unit for Epidemiology, Department of Public Health, Aarhus University, Aarhus C, Denmark.,Department of Clinical Epidemiology, Aarhus University Hospital, Aarhus N, Denmark.,Department of Epidemiology, Fielding School of Public Health, University of California Los Angeles (UCLA), Los Angeles, California, USA
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Østergaard CS, Ernst A, Gaml-Sørensen A, Brix N, Toft G, Haervig KK, Hougaard KS, Bonde JP, Tøttenborg SS, Ramlau-Hansen CH. Use of paracetamol (acetaminophen) as a nonprescription analgesic and semen quality in young men: A cross-sectional study. Andrology 2021; 10:495-504. [PMID: 34779581 DOI: 10.1111/andr.13129] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Revised: 08/31/2021] [Accepted: 11/08/2021] [Indexed: 11/27/2022]
Abstract
BACKGROUND Paracetamol (acetaminophen) is a frequently used nonprescription analgesic with suggested endocrine-disrupting properties. Epidemiological evidence on the effect of paracetamol on male fecundity is sparse. OBJECTIVES To investigate if the use of paracetamol as an oral nonprescription mild analgesic was associated with semen quality in young men. MATERIALS AND METHODS This cross-sectional study was based on data from the Fetal Programming of Semen Quality (FEPOS; 2017-2019) cohort of 1058 young men (18-21 years) included in the Danish National Birth Cohort. Participants completed a comprehensive online questionnaire on health behavior including analgesic use and provided a semen sample. Negative binomial regression models were used to estimate the percentage differences (adjusted mean ratios [aMR]) in semen quality characteristics according to paracetamol use (no; yes) and frequency of use (almost never; <1/month; ≥1/month; ≥1/week). RESULTS In total, 28% of the 913 participants with available data reported the use of paracetamol within the last 6 months. We found a slightly higher total sperm count (aMR 1.13 95% CI [0.99-1.30]) in users compared to nonusers but other semen characteristics were unaffected. The frequency of use was suggestive of lower total sperm count and morphologically normal sperm cells primarily among users ≥1/week, however, CIs were wide. DISCUSSION We were unable to account for the underlying reason for paracetamol use, which may induce confounding by indication. Exposure misclassification due to recall is likely but probably nondifferential due to the participants' young age and unawareness of semen quality. Due to the rapid plasma half-life of paracetamol and few frequent users, it was not possible to conclude on potential high-dose effects. CONCLUSION Our findings do not suggest any strong detrimental effect of paracetamol use on semen quality within this sample of young Danish men. However, the effects of high dose and frequent use cannot be excluded.
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Affiliation(s)
| | - Andreas Ernst
- Department of Public Health, Research Unit for Epidemiology, Aarhus University, Aarhus, Denmark.,Department of Urology, Aarhus University Hospital, Aarhus, Denmark
| | - Anne Gaml-Sørensen
- Department of Public Health, Research Unit for Epidemiology, Aarhus University, Aarhus, Denmark
| | - Nis Brix
- Department of Public Health, Research Unit for Epidemiology, Aarhus University, Aarhus, Denmark.,Department of Clinical Genetics, Aarhus University Hospital, Aarhus, Denmark
| | - Gunnar Toft
- Steno Diabetes Center Aarhus, Aarhus University Hospital, Aarhus, Denmark
| | - Katia Keglberg Haervig
- Department of Occupational and Environmental Medicine, Bispebjerg and Frederiksberg Hospital, University of Copenhagen, Copenhagen, Denmark
| | - Karin Sørig Hougaard
- Department of Public Health, Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark.,National Research Centre for the Working Environment, Copenhagen, Denmark
| | - Jens Peter Bonde
- Department of Occupational and Environmental Medicine, Bispebjerg and Frederiksberg Hospital, University of Copenhagen, Copenhagen, Denmark.,Department of Public Health, Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Sandra Søgaard Tøttenborg
- Department of Occupational and Environmental Medicine, Bispebjerg and Frederiksberg Hospital, University of Copenhagen, Copenhagen, Denmark
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Gaml-Sørensen A, Brix N, Ernst A, Lunddorf LLH, Ramlau-Hansen CH. Father Absence in Pregnancy or During Childhood and Pubertal Development in Girls and Boys: A Population-Based Cohort Study. Child Dev 2021; 92:1494-1508. [PMID: 33400273 DOI: 10.1111/cdev.13488] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2020] [Revised: 07/11/2020] [Accepted: 09/06/2020] [Indexed: 12/17/2022]
Abstract
This cohort study, including 15,810 children born 2000-2003 in Denmark, aimed to investigate the association between father absence in pregnancy or during childhood and pubertal development in girls and boys. The children were followed from 11 years of age and throughout pubertal development. Mean age differences according to exposure groups were estimated for each pubertal marker separately and for a combined pubertal marker. The results suggested that father absence in pregnancy and during childhood was associated with earlier pubertal development in girls, and father absence from late childhood was associated with earlier pubertal development in boys. The paternal investment theory, the psychosocial acceleration theory and the energetics theory were explored, and did not seem to explain the observed associations.
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Gaml-Sørensen A, Brix N, Ernst A, Lunddorf LLH, Sand SA, Ramlau-Hansen CH. Prenatal exposure to antibiotics and timing of puberty in sons and daughters: A population-based cohort study. Eur J Obstet Gynecol Reprod Biol 2020; 250:1-8. [PMID: 32361341 DOI: 10.1016/j.ejogrb.2020.04.031] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2019] [Revised: 04/01/2020] [Accepted: 04/13/2020] [Indexed: 11/26/2022]
Abstract
OBJECTIVE To investigate if prenatal exposure to antibiotics is associated with earlier timing of pubertal development in sons and daughters. STUDY DESIGN This population-based cohort study is based upon the Puberty Cohort and includes a sample of 15,638 children born 2000-2003 in Denmark. Information on maternal use of antibiotics was collected around gestational week 30 and 6 months postpartum. The children were followed-up half-yearly from 11 years of age and throughout sexual maturation providing information on Tanner stages, acne and axillary hair, in addition to voice break and first ejaculation in sons and menarche in daughters. Due to the half-yearly collection of data on pubertal timing, the data was censored and therefore analysed using a multivariable censored time-to-event regression model. We examined both prenatal exposure to antibiotics at any time in pregnancy and trimester-specific prenatal exposure to antibiotics and pubertal timing, adjusting for maternal baseline socioeconomic and lifestyle characteristics. Mean age differences for the pubertal milestones between exposure groups were estimated. A combined estimate for overall pubertal timing was calculated based on combining all pubertal milestones into one model for sons and daughters, using Huber-White robust variance estimation which handles the risk of type 1 errors due to multiple testing of correlated outcomes. An active comparator approach with restriction to women reporting to have a urinary tract infection (cystitis) treated with either penicillin or sulfonamides was employed in a sub-analysis. RESULTS The prevalence of any maternal use of antibiotics in pregnancy was 21.1 %. There was no association between prenatal exposure to antibiotics and timing of pubertal development for the individual milestones. The adjusted combined estimate for pubertal timing in sons prenatally exposed to antibiotics at any point in pregnancy was -0.4 (95 % confidence interval (CI): -1.2; 0.4) months compared to unexposed sons. The adjusted combined estimate for pubertal timing in daughters prenatally exposed to antibiotics at any point in pregnancy was -0.1 (95 % CI: -0.9; 0.7) months compared to unexposed daughters. Both the trimester-specific analyses and the active comparator analysis revealed similar results. CONCLUSION Prenatal exposure to antibiotics was not associated with pubertal timing.
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Affiliation(s)
- Anne Gaml-Sørensen
- Department of Public Health, Research Unit for Epidemiology, Aarhus University, Bartholins Allé 2, 8000, Aarhus C., Denmark.
| | - Nis Brix
- Department of Public Health, Research Unit for Epidemiology, Aarhus University, Bartholins Allé 2, 8000, Aarhus C., Denmark
| | - Andreas Ernst
- Department of Public Health, Research Unit for Epidemiology, Aarhus University, Bartholins Allé 2, 8000, Aarhus C., Denmark; Department of Urology, Aarhus University Hospital, Palle Juul-Jensens Boulevard 99, 8200, Aarhus N, Denmark
| | - Lea L H Lunddorf
- Department of Public Health, Research Unit for Epidemiology, Aarhus University, Bartholins Allé 2, 8000, Aarhus C., Denmark
| | - Sofie A Sand
- Department of Public Health, Research Unit for Epidemiology, Aarhus University, Bartholins Allé 2, 8000, Aarhus C., Denmark
| | - Cecilia H Ramlau-Hansen
- Department of Public Health, Research Unit for Epidemiology, Aarhus University, Bartholins Allé 2, 8000, Aarhus C., Denmark
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Sand SA, Ernst A, Lunddorf LLH, Brix N, Gaml-Sørensen A, Ramlau-Hansen CH. In Utero Exposure to Glucocorticoids and Pubertal Timing in Sons and Daughters. Sci Rep 2019; 9:20374. [PMID: 31889153 PMCID: PMC6937234 DOI: 10.1038/s41598-019-56917-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2019] [Accepted: 12/17/2019] [Indexed: 11/29/2022] Open
Abstract
Early pubertal timing has been associated with adult diseases, and identifying preventable causes is of importance. In utero exposure to exogenous glucocorticoids, has been associated with changes in the reproductive hormonal axes in the children, which may influence pubertal timing. Exogenous glucocorticoids can be indicated for diseases such as asthma, allergy, skin diseases, as well as muscle and joint diseases. The aim was to explore the association between in utero exposure to glucocorticoids and pubertal timing in the children. This population-based study was conducted in the Puberty Cohort including 15,819 children, which is a sub-cohort of the Danish National Birth Cohort. Information on maternal glucocorticoid treatment was collected through interviews during pregnancy. Information on pubertal timing was obtained by questionnaires every 6 months throughout puberty, including Tanner Stages, axillary hair, acne, voice break, first ejaculation and menarche. The potential impact of confounding by indication was explored by stratifying on indication and treatment status. Overall, 6.8% of the children were exposed to glucocorticoids in utero. Exposure to glucocorticoids in utero was not associated with earlier puberty for neither boys nor girls with combined estimates of 0.4 months (95% CI: –1.5; 2.2) and –0.7 months (95% CI: –2.5; 1.2).
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Affiliation(s)
- Sofie Aagaard Sand
- Department of Public Health, Research Unit for Epidemiology, Aarhus University, Aarhus, Denmark.
| | - Andreas Ernst
- Department of Public Health, Research Unit for Epidemiology, Aarhus University, Aarhus, Denmark.,Department of Urology, Aarhus University Hospital, Aarhus, Denmark
| | | | - Nis Brix
- Department of Public Health, Research Unit for Epidemiology, Aarhus University, Aarhus, Denmark
| | - Anne Gaml-Sørensen
- Department of Public Health, Research Unit for Epidemiology, Aarhus University, Aarhus, Denmark
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