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Dermitzakis I, Theotokis P, Axarloglou E, Delilampou E, Miliaras D, Meditskou S, Manthou ME. The Impact of Lifestyle on the Secondary Sex Ratio: A Review. Life (Basel) 2024; 14:662. [PMID: 38929646 PMCID: PMC11205111 DOI: 10.3390/life14060662] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2024] [Revised: 05/11/2024] [Accepted: 05/21/2024] [Indexed: 06/28/2024] Open
Abstract
The secondary sex ratio (SSR), indicating the ratio of male to female live births, has garnered considerable attention within the realms of reproductive biology and public health. Numerous factors have been posited as potential trendsetters of the SSR. Given the extensive research on the impact of daily behaviors and habits on individuals' reproductive health, there is a plausible suggestion that lifestyle choices may also influence the SSR. By synthesizing the existing literature on the current research field, this comprehensive review indicates that an elevated SSR has been associated with an increased intake of fatty acids and monosaccharides, proper nutrition, higher educational levels, financial prosperity, and favorable housing conditions. On the other hand, a decreased SSR may be linked to undernutrition, socioeconomic disparities, and psychological distress, aligning with the Trivers-Willard hypothesis. Occupational factors, smoking habits, and cultural beliefs could also contribute to trends in the SSR. Our review underscores the significance of considering the aforementioned factors in studies examining the SSR and emphasizes the necessity for further research to unravel the mechanisms underpinning these connections. A more profound comprehension of SSR alterations due to lifestyle holds the potential to adequately develop public health interventions and healthcare strategies to enhance reproductive health and overall well-being.
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Affiliation(s)
| | | | | | | | | | | | - Maria Eleni Manthou
- Department of Histology-Embryology, School of Medicine, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece; (I.D.); (P.T.); (E.A.); (E.D.); (D.M.); (S.M.)
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Fishman R, Kralj-Fišer S, Marglit S, Koren L, Vortman Y. Fathers and sons, mothers and daughters: Sex-specific genetic architecture for fetal testosterone in a wild mammal. Horm Behav 2024; 161:105525. [PMID: 38452612 DOI: 10.1016/j.yhbeh.2024.105525] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/11/2023] [Revised: 01/13/2024] [Accepted: 02/29/2024] [Indexed: 03/09/2024]
Abstract
Testosterone plays a critical role in mediating fitness-related traits in many species. Although it is highly responsive to environmental and social conditions, evidence from several species show a heritable component to its individual variation. Despite the known effects that in utero testosterone exposure have on adult fitness, the heritable component of individual testosterone variation in fetuses is mostly unexplored. Furthermore, testosterone has sex-differential effects on fetal development, i.e., a specific level may be beneficial for male fetuses but detrimental for females, producing sexual conflict. Such sexual conflict may be resolved by the evolution of a sex-specific genetic architecture of the trait. Here, we quantified fetal testosterone levels in a wild species, free-ranging nutrias (Myocastor coypus) using hair-testing and estimated testosterone heritability between parent and offspring from the same and opposite sex. We found that in utero accumulated hair testosterone levels were heritable between parents and offspring of the same sex. Moreover, there was a low additive genetic covariance between the sexes, and a low cross-sex genetic correlation, suggesting a potential for sex-specific trait evolution, expressed early on, in utero.
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Affiliation(s)
- Ruth Fishman
- Department of Brain Sciences, Weizmann Institute of Science, Rehovot 76100, Israel(1); The Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan 5290002, Israel.
| | - Simona Kralj-Fišer
- Scientific and Research Centre of the Slovenian Academy of Sciences and Arts, Jovan Hadži Institute of Biology, Evolutionary Zoology Laboratory, Ljubljana, Slovenia.
| | - Sivan Marglit
- Hula Research Center, Department of Animal Sciences, Tel-Hai College, Upper Galilee 1220800, Israel
| | - Lee Koren
- The Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan 5290002, Israel.
| | - Yoni Vortman
- Hula Research Center, Department of Animal Sciences, Tel-Hai College, Upper Galilee 1220800, Israel; MIGAL-Galilee Research Institute, 11016 Kiryat Shmona, Israel
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Sociodemographic and Biological Factors of Health Disparities of Mothers and Their Very Low Birth-Weight Infants. Adv Neonatal Care 2022; 22:E169-E181. [PMID: 35588063 PMCID: PMC9422772 DOI: 10.1097/anc.0000000000000997] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
BACKGROUND Black mothers and their very low birth-weight infants in the United States have increased risk of adverse neonatal and maternal health outcomes compared with White mothers and infants. Disparities in adverse birth outcomes associated with sociodemographic factors are difficult to quantify and modify, limiting their usefulness in assessing intervention effects. PURPOSE To test hypotheses that (1) the biological factors of maternal testosterone and cortisol are associated with sociodemographic factors and (2) both factors are associated with neonatal health and maternal mental health and healthy behaviors between birth and 40 weeks' gestational age. METHODS We used a descriptive, longitudinal design. Eighty-eight mothers and very low birth-weight neonates were recruited from a tertiary medical center in the United States. Data on sociodemographic factors and neonatal health were collected from medical records. Maternal mental health and healthy behaviors were collected with questionnaires. Maternal salivary testosterone and cortisol levels were measured using enzyme immunoassays. Data were analyzed primarily using general linear and mixed models. RESULTS High testosterone and/or low cortisol levels were associated with younger age, less education, enrollment in a federal assistance program, being unmarried, being Black, poorer neonatal health, and delayed physical growth. Low cortisol level was related to higher levels of depressive symptoms. Black mothers had fewer healthy behaviors than White mothers. IMPLICATIONS FOR PRACTICE AND RESEARCH Findings confirm that biological factors are associated with sociodemographic factors, and both are associated with neonatal health and maternal mental health and healthy behaviors. We propose using sociodemographic and biological factors concurrently to identify risk and develop and evaluate ante- and postpartum interventions.Video abstract available athttps://journals.na.lww.com/advancesinneonatalcare/Pages/videogallery.aspx?autoPlay=false&videoId=59.
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Fukuda M, Fukuda K, Mason S, Tatsumi K, Shimizu T, Akahori T, Matsumoto T, Tahara M, Andersen CY. Ovulation patterns affect the offspring sex ratios and change with the women's age. Reprod Health 2022; 19:159. [PMID: 35804411 PMCID: PMC9270783 DOI: 10.1186/s12978-022-01462-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2021] [Accepted: 06/21/2022] [Indexed: 11/23/2022] Open
Abstract
Background The aim of this study was to evaluate whether women’s ages at conception and the ratio of male to female infants are associated with various ovulation patterns. Methods An observational clinical study was conducted in private OB/GYN clinics. Infertile women with regular menstrual cycles receiving intrauterine insemination (IUI) and/or in-vitro fertilization (IVF) had their ovulation patterns monitored in three consecutive spontaneous cycles receiving infertility treatment in the third cycle. Ovulation patterns were also observed in women with slight ovulation disorders during IUI and/or IVF in clomiphene citrate stimulated cycles. All the pregnant women’s ages at conception and their respective offspring sex ratios were compared to various ovulation patterns. Statistical evaluation was performed using ANOVA, unpaired t test, χ2 test or Fisher’s exact test, heterogeneity χ2 test, odds ratios at 95% confidence intervals and logistic regression. Results Contralateral ovulation (i.e. ovulation jumping from ovary to the other) was more often observed in relatively younger women, who showed a higher probability of having a boy than after ipsilateral ovulation. There was a significantly higher frequency of boys being conceived following three consecutive ovulations with a left–left–right (LLR) ovulation pattern, while three ovulations from the left ovary (LLL) were associated with a higher frequency of girls. We also found two consecutive menstrual cycles the left–right (LR) ovulation pattern showed a similar significant difference compared to the left-left (LL) ovulation. Both the infertile and infertile + fertile women groups showing right-sided ovulation, regardless of age, showed significantly higher offspring sex ratio compared to left-sided ovulation, which was not observed in the group of fertile women alone. Conclusions LLR, LR and contralateral ovulation happens more often in younger women and favors male offspring in infertile women. Right-sided ovulation favors male offspring in infertile and infertile + fertile women, which was not observed in the group of fertile women. It is of interest to evaluate whether ovulation patterns change with women’s ages at conception and affect offspring sex ratios. An observational clinical study was conducted in private OB/GYN clinics. Infertile women with regular menstrual cycles receiving intrauterine insemination (IUI) and/or in-vitro fertilization (IVF) had their ovulation patterns monitored in three consecutive spontaneous cycles receiving infertility treatment in the third cycle. Ovulation patterns were also observed in women with slight ovulation disorder during IUI and/or IVF in clomiphene citrate stimulated cycles. Women’s ages and offspring sex ratios were compared to various ovulation patterns. The contralateral ovulation was more often observed in relatively younger women, who showed a higher probability of having a boy than following a pregnancy after ipsilateral ovulation. There was a significantly higher frequency of boys being conceived following three consecutive ovulations with after a left-left-right (LLR) ovulation pattern, while three ovulations from the left ovary (LLL) were associated with a higher frequency of girls. Only considering two consecutive menstrual cycles the left-right (LR) ovulation pattern showed a similar significant difference compared to the left-left (LL) ovulation. Both infertile and infertile + fertile women showing right-sided ovulation, regardless of age, showed significantly higher offspring sex ratio compared to left-sided ovulation, which was not observed in the group of fertile women alone. LLR, LR and contralateral ovulation happens more often in younger women and favor male offspring in infertile women. Right-sided ovulation favors male offspring in infertile and infertile + fertile women, which was not observed in the group of fertile women.
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Affiliation(s)
- Misao Fukuda
- M&K Health Institute, 30-9 Kariya, , Ako, Hyogo, 678-0239, Japan.
| | - Kiyomi Fukuda
- M&K Health Institute, 30-9 Kariya, , Ako, Hyogo, 678-0239, Japan
| | - Shawn Mason
- M&K Health Institute, 30-9 Kariya, , Ako, Hyogo, 678-0239, Japan
| | - Kenichi Tatsumi
- Umegaoka Women's Hospital, 1-33-3 Umegaoka, Setagaya-ku, Tokyo, 154-0022, Japan
| | - Takashi Shimizu
- Shimizu Women's Clinic, 2-2-4 Minamiguchi, Takarazuka, Hyogo, 665-0011, Japan
| | | | | | - Masahiro Tahara
- Taniguchi Hospital, 1-5-20 Oonishi, Izumisano City, 598-0043, Japan.,Nomura Clinic, 3-2-28 Chuo-ku Takatsu, Osaka, 542-0072, Japan
| | - Claus Yding Andersen
- Laboratory of Reproductive Biology, Juliane Marie Center, Rigshospitalet, Section 5712, University Hospital of Copenhagen, Blegdamsvej 9, 2100, Copenhagen, Denmark
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Alon T, Matas D, Koren L, Gootwine E. Higher cortisol and testosterone levels in sheep with larger litter sizes. Livest Sci 2021. [DOI: 10.1016/j.livsci.2020.104381] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Kaňková Š, Flegr J, Toman J, Calda P. Maternal RhD heterozygous genotype is associated with male biased secondary sex ratio. Early Hum Dev 2020; 140:104864. [PMID: 31500940 DOI: 10.1016/j.earlhumdev.2019.104864] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
BACKGROUND Previous studies suggest that RhD positive heterozygotes express better health status than RhD positive homozygotes and especially RhD negative subjects. This also applies to pregnant women. According to the Trivers-Willard hypothesis, women in better physical condition should have more sons. AIM To test the hypothesis that RhD positive heterozygous mothers have a male-skewed sex ratio. STUDY DESIGN Cross-sectional study. The data was analysed using Chi-Square test for all women, separately for RhD positive and RhD negative women, and separately for primiparous and multiparous women. The effects of maternal weight as a continuous predictor and the RhD phenotype of newborn as a categorical predictor of newborn sex were evaluated by the generalized linear model (GLZ) separately for RhD positive and RhD negative women using binomial distribution and logit link function. OUTCOME MEASURES Clinical records comprised maternal weight before pregnancy, number of previous deliveries, sex of the newborn, maternal RhD phenotype, and RhD phenotype of the newborn. SUBJECTS We analysed data from 5655 women who gave birth between 2008 and 2012 in General University Hospital in Prague. RESULTS Secondary sex ratio was significantly higher (P = 0.028) in RhD positive mothers who had RhD negative newborns, i.e., in heterozygotes (SR = 1.23), than in RhD positive mothers who had RhD positive newborns, i.e., in a mixed population of heterozygotes and homozygotes (SR = 1.00), especially in primiparous women (P = 0.013; SR = 1.37 and 0.99 resp.). CONCLUSION The sex ratio at birth was significantly higher in RhD positive mothers who had RhD negative newborns than in RhD positive mothers who had RhD positive newborns.
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Affiliation(s)
- Šárka Kaňková
- Department of Philosophy and History of Science, Faculty of Science, Charles University, Prague CZ-128 44, Prague 2, Czech Republic.
| | - Jaroslav Flegr
- Department of Philosophy and History of Science, Faculty of Science, Charles University, Prague CZ-128 44, Prague 2, Czech Republic
| | - Jan Toman
- Department of Philosophy and History of Science, Faculty of Science, Charles University, Prague CZ-128 44, Prague 2, Czech Republic
| | - Pavel Calda
- Department of Obstetrics and Gynaecology, General University Hospital and First Faculty of Medicine, Charles University, Prague CZ-128 08, Prague 2, Czech Republic
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Can hair steroids predict pregnancy longevity? Reprod Biol 2018; 18:410-415. [DOI: 10.1016/j.repbio.2018.09.004] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2018] [Revised: 09/06/2018] [Accepted: 09/08/2018] [Indexed: 11/21/2022]
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Female-biased sex ratios are associated with higher maternal testosterone levels in nutria (Myocastor coypus). Behav Ecol Sociobiol 2018. [DOI: 10.1007/s00265-018-2517-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
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James WH, Grech V. Can sex ratios at birth be used in the assessment of public health, and in the identification of causes of selected pathologies? Early Hum Dev 2018; 118:15-21. [PMID: 29428574 DOI: 10.1016/j.earlhumdev.2018.02.003] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/23/2017] [Revised: 12/31/2017] [Accepted: 02/06/2018] [Indexed: 02/09/2023]
Abstract
This paper will consist of two parts. In the first, further support is given to the proposal that offspring sex ratios (proportions male) may usefully be regarded as indicators of public health. In the second, it is shown that sex ratios may help in the identification of the causes and effects of several pathologies that seriously impinge on public health viz. autism, testicular cancer, hepatitis B and toxoplasmosis.
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Affiliation(s)
- William H James
- Galton Laboratory, Department of Genetics, Evolution and Environment, University College London, London WC1E 6HH, UK
| | - Victor Grech
- Victor Grech, Academic Department of Paediatrics, University of Malta Medical School, Msida, Malta.
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10
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James WH, Grech V. Homosexual Sons and the Fraternal Birth Order Effect: The Role of Elevated Maternal Intrauterine Testosterone. ARCHIVES OF SEXUAL BEHAVIOR 2018; 47:33-36. [PMID: 29159753 DOI: 10.1007/s10508-017-1113-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/27/2017] [Accepted: 11/01/2017] [Indexed: 06/07/2023]
Affiliation(s)
- William H James
- Galton Laboratory, Department of Genetics, Evolution and Environment, University College London, London, WC1E 6HH, UK.
| | - Victor Grech
- Paediatric Department, University of Malta Medical School, Msida, Malta
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Abstract
The human sex ratio (proportion male) at birth (SRB) varies with many variables. Some of this variation has an established proximate cause. For instance, low SRB (more females) at birth are associated with various forms of stressful events or circumstances during or prior to pregnancy. These low SRB are almost certainly mainly caused by maternal-stress-induced male foetal loss. Other types of SRB variation are thought to be caused by hormonal variation in either or both parents around the time of conception. One or other of these two types of proximate cause seems to be responsible for most of the established variation of SRB. This will be illustrated here in respect of some selected forms of SRB variation. It seems likely that a clarification of the hormonal causes of SRB variation will also help explain the striking (apparent) inconsistencies in the results of reported tests of the influential Trivers-Willard hypothesis. It is further proposed that an appreciation of the evidence that parental hormones influence SRB may enhance understanding of several important pathologies (hepatitis B, toxoplasmosis, testicular cancer, prostate cancer and autism).
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Affiliation(s)
- William H James
- The Galton Laboratory, Department of Genetics, Evolution and Environment, University College London, United Kingdom.
| | - Victor Grech
- Department of Paediatrics, Mater Dei Hospital Medical School, Malta.
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Bae J, Lynch CD, Kim S, Sundaram R, Sapra KJ, Buck Louis GM. Preconception stress and the secondary sex ratio in a population-based preconception cohort. Fertil Steril 2017; 107:714-722. [PMID: 28104242 DOI: 10.1016/j.fertnstert.2016.12.011] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2016] [Revised: 11/23/2016] [Accepted: 12/12/2016] [Indexed: 12/16/2022]
Abstract
OBJECTIVE To examine the association between preconception parental stress and the secondary sex ratio, defined as the ratio of males to females at birth. DESIGN A population-based preconception cohort. SETTING Not applicable. PATIENT(S) A total of 235 couples who were enrolled before conception in Michigan and Texas between 2005 and 2009 and who had a singleton birth during the follow-up period. Couples were interviewed separately at baseline to obtain information on perceived stress (Cohen's Perceived Stress Scale) and lifetime history of physician-diagnosed anxiety and/or mood disorders. Female partners were also trained to collect basal saliva samples for the measurement of salivary stress markers, alpha-amylase and cortisol. INTERVENTION(S) None. MAIN OUTCOME MEASURE(S) Birth outcome data including infant sex were collected upon delivery. Modified Poisson regression models were used to estimate the relative risks (RRs) of a male birth for each stress marker. RESULT(S) After adjusting for potential confounders, we observed a 76% increase in the risk of fathering a male infant (RR 1.76; 95% confidence interval 1.17-2.65) in men diagnosed with anxiety disorders compared with those who were not diagnosed. When lifetime history of physician-diagnosed anxiety disorders was modeled jointly for the couple, the association was slightly strengthened (RR 2.03; 95% confidence interval 1.46-2.84). CONCLUSION(S) This prospective cohort study suggests that paternal lifetime history of physician-diagnosed anxiety disorders may be associated with an increase in the secondary sex ratio, resulting in an excess of male births.
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Affiliation(s)
- Jisuk Bae
- Department of Preventive Medicine, Catholic University of Daegu School of Medicine, Daegu, South Korea; Division of Intramural Population Health Research, Eunice Kennedy Shriver National Institute of Child Health and Human Development, Bethesda, Maryland.
| | - Courtney D Lynch
- Department of Obstetrics and Gynecology, The Ohio State University College of Medicine, Columbus, Ohio
| | - Sungduk Kim
- Division of Intramural Population Health Research, Eunice Kennedy Shriver National Institute of Child Health and Human Development, Bethesda, Maryland
| | - Rajeshwari Sundaram
- Division of Intramural Population Health Research, Eunice Kennedy Shriver National Institute of Child Health and Human Development, Bethesda, Maryland
| | - Katherine J Sapra
- Division of Intramural Population Health Research, Eunice Kennedy Shriver National Institute of Child Health and Human Development, Bethesda, Maryland
| | - Germaine M Buck Louis
- Division of Intramural Population Health Research, Eunice Kennedy Shriver National Institute of Child Health and Human Development, Bethesda, Maryland
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James WH. The sex ratio of the sibs of probands diagnosed with autism. J Theor Biol 2016; 400:154-7. [DOI: 10.1016/j.jtbi.2016.03.020] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2015] [Revised: 02/10/2016] [Accepted: 03/13/2016] [Indexed: 01/02/2023]
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Hogue CJ. Invited Commentary: Preventable Pregnancy Loss Is a Public Health Problem. Am J Epidemiol 2016; 183:709-12. [PMID: 27009345 DOI: 10.1093/aje/kww004] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2015] [Accepted: 12/04/2015] [Indexed: 11/14/2022] Open
Abstract
Pregnancy loss is common and can lead to long-standing parental depression and related problems. In this issue, a study of Danish registries by Bruckner et al. (Am J Epidemiol. 2016;183(8):701-708) correlates monthly trends in unemployment with monthly trends in reported spontaneous abortion, lagged by 1 month. The observed association might be caused by a general population phenomenon, as suggested by the authors, or might represent an increased miscarriage risk only within the subset of the population that is directly affected by lost income. Preventive interventions will vary depending on which interpretation is more likely. Research into the preventability of miscarriages and stillbirths is hampered in the United States by poor-quality vital registration of these events. Investment in improved surveillance systems is needed and would be worthwhile, as illustrated by the knowledge gained about the black/white gap in infant mortality when national birth and infant death records began to be linked. In addition, institution of the Pregnancy Risk Assessment Monitoring System in 1987 shed light on the association of stressful life events with poor birth outcomes. That system can be improved by sampling women who have experienced stillbirths. Better data would facilitate not only surveillance but also hypothesis-generating epidemiologic studies for identifying preventable pregnancy loss.
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Abstract
There is evidence that the human sex ratio (proportion males at birth) is the result of two processes. First, the sexes of zygotes (from which the primary sex ratio would be calculated) are thought to be partially controlled by the hormone levels of both parents around the time of conception. Second, this primary sex ratio is apparently modified downwards by male-sex-selective spontaneous abortion caused by high levels of maternal stress-induced adrenal androgens, thus yielding the sex ratio at birth (the secondary sex ratio). Since maternal stress is one cause of spontaneous abortion (and of other forms of reproductive sub-optimality), and since some forms of pharmacological treatment of maternal stress are deleterious to the foetus, best practice would suggest non-pharmacological treatment (e.g. psychotherapy, hypnosis or massage) for pregnant women who have a previous history of spontaneous abortion, preterm birth or low-birth-weight infants.
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Affiliation(s)
- William H James
- The Galton Laboratory, Department of Genetics, Evolution and Environment, University College London, UK.
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Pongou R. Sex Differences in Early-Age Mortality: The Preconception Origins Hypothesis. Demography 2015; 52:2053-6. [PMID: 26527470 DOI: 10.1007/s13524-015-0441-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Roland Pongou
- Department of Economics, University of Ottawa, 120 University, Social Sciences Building, Room 9005, Ottawa, Ontario, Canada, K1N 6N5.
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An Environmental Cause Common to Sex Determination and Infant Mortality. Demography 2015; 52:2051-2. [PMID: 26438319 DOI: 10.1007/s13524-015-0436-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Abstract
Prenatal stress is known to alter hypothalamic-pituitary-adrenal axis activity, and more recent evidence suggests that it may also affect androgen activity. In animal models, prenatal stress disrupts the normal surge of testosterone in the developing male, whereas in females, associations differ by species. In humans, studies show that (1) associations between prenatal stress and child outcomes are often sex-dependent, (2) prenatal stress predicts several disorders with notable sex differences in prevalence, and (3) prenatal exposure to stressful life events may be associated with masculinized reproductive tract development and play behavior in girls. In this minireview, we examine the existing literature on prenatal stress and androgenic activity and present new, preliminary data indicating that prenatal stress may also modify associations between prenatal exposure to diethylhexyl phthalate, (a synthetic, antiandrogenic chemical) and reproductive development in infant boys. Taken together, these data support the hypothesis that prenatal exposure to both chemical and nonchemical stressors may alter sex steroid pathways in the maternal-placental-fetal unit and ultimately alter hormone-dependent developmental endpoints.
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Affiliation(s)
- Emily S Barrett
- Department of Obstetrics and Gynecology (E.S.B.), University of Rochester School of Medicine and Dentistry, Rochester, New York 14642; and Department of Preventive Medicine (S.H.S.), Icahn School of Medicine at Mt Sinai, New York, New York 10029
| | - Shanna H Swan
- Department of Obstetrics and Gynecology (E.S.B.), University of Rochester School of Medicine and Dentistry, Rochester, New York 14642; and Department of Preventive Medicine (S.H.S.), Icahn School of Medicine at Mt Sinai, New York, New York 10029
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Dean RG, Dean J, Heller GZ, Leader LR. A mass shooting at Port Arthur, Tasmania, Australia: a study of its impact on early pregnancy losses using a conception time-based methodology. Hum Reprod 2015; 30:2671-6. [PMID: 26355115 DOI: 10.1093/humrep/dev200] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2014] [Accepted: 07/23/2015] [Indexed: 01/31/2023] Open
Abstract
STUDY QUESTION Does an acute calamity in a community cause early miscarriage and is this association the same for male and female fetuses? SUMMARY ANSWER Estimated losses of 29.5% of first trimester pregnancies in the affected region could be associated with an acute calamity, with no statistically significant difference in estimated losses by fetal sex. WHAT IS KNOWN ALREADY There are very few studies on the impact of a calamity on early pregnancy loss and its differential effects on male and female fetuses. A decline in the human sex ratio at birth associated with the events of 9/11 in New York has been documented. STUDY DESIGN, SIZE, DURATION This is a retrospective descriptive study of birth register data in Tasmania, Australia, from 1991 to 1997, covering the period in which the calamity occurred. The register contains data on all pregnancies that proceeded to >20 weeks gestation. The conception date was calculated by subtracting gestational age from birth date. We estimated that 40 318 pregnancies were conceived in the period 1991-1996 inclusive. These were aggregated to 4-weekly blocks classified by region and sex. PARTICIPANTS/MATERIALS, SETTING, METHODS The acute calamity was at Port Arthur, Tasmania, Australia. On 28 April 1996, a gunman opened fire on visitors and staff in a tourist cafe. A very stressful 20 h period, ended with 35 people dead and 22 injured. A negative binomial regression model was used to assess the association between this calamity and pregnancy loss. This loss is evidenced by a shortfall in the registration of pregnancies that were in their first trimester at the time of the calamity. MAIN RESULTS AND THE ROLE OF CHANCE We estimated a shortfall of 29.5% or 229 registered pregnancies among those in the first trimester at the time of the calamity (P < 0.001), in the region surrounding the calamity site. There was no sex effect in this shortfall (P = 0.911). There was no corresponding shortfall in other parts of Tasmania (P = 0.349). LIMITATIONS, REASONS FOR CAUTION The study is descriptive and cannot produce causal inferences. These first trimester miscarriages are estimated statistically and it is understood that gestational age is an estimate. The use of maternal residential postcodes at birth as a surrogate for geographic area or space assumes that the mother has not moved into the postcode area after the calamity and before the reporting of a birth. WIDER IMPLICATIONS OF THE FINDINGS The results of this study suggest that calamities bring about significant pregnancy loss affecting both sexes. The methodology presented of inferring conception date from birth date and using this for analysis, provides a more accurate assessment of first trimester pregnancy losses than raw birth data or sex ratio at birth.
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Affiliation(s)
- R G Dean
- School of Women's and Children's Health, Medical Faculty, The University of New South Wales, Kensington, NSW 2052, Australia
| | - J Dean
- formerly, AIHW National Perinatal Epidemiology and Statistics Unit, School of Women's and Children's Health, Medical Faculty, The University of New South Wales, Kensington, NSW 2052, Australia (now retired)
| | - G Z Heller
- Department of Statistics, Macquarie University, Sydney, NSW, Australia
| | - L R Leader
- School of Women's and Children's Health, Medical Faculty, The University of New South Wales, Kensington, NSW 2052, Australia
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Kankova S, Flegr J, Calda P. The influence of latent toxoplasmosis on women's reproductive function: four cross-sectional studies. Folia Parasitol (Praha) 2015; 62. [DOI: 10.14411/fp.2015.041] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2015] [Accepted: 05/30/2015] [Indexed: 11/19/2022]
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