REPRODUCTION IN HIGH ALTITUDE AYMARA: PHYSIOLOGICAL STRESS AND FERTILITY PLANNING?

2002 ◽  
Vol 34 (4) ◽  
pp. 463-473 ◽  
Author(s):  
E. CROGNIER ◽  
M. VILLENA ◽  
E. VARGAS
Keyword(s):  
High Altitude ◽  
Physiological Stress ◽  
Late Onset ◽  
Cultural Control ◽  
Age At Menarche ◽  
Reproductive Pattern ◽  
Age At First Birth ◽  
First Birth ◽  
Birth Intervals ◽  
Live Births

Reproductive characteristics at high altitude are described based on the reproductive histories of 720 Aymara women, collected in 1998 and 1999 in a group of twelve peasant communities at a mean altitude of 4000 m in the Bolivian Altiplano. The reproductive pattern is shaped by a late onset of childbearing, associated with a rather short reproductive span and large birth intervals. Environmental conditions could explain the particularly late age at menarche of rural girls compared with their urban counterparts, whereas the age at first birth is likely to be under cultural control. The short reproductive span appears to result from a large mean interval between last birth and menopause, which is essentially determined by cultural decisions. The birth intervals, which are longer than in many traditional societies, could be the result of a slower restoration of postpartum fecundability induced by the hard way of life inherent in the Altiplano (including poor sanitary and nutritional conditions and high workload), perhaps aggravated by hypoxia. However, a secular trend in fertility is perceptible, towards earlier menarche, earlier age at first birth, increasing reproductive span and a slight increase in live births and surviving offspring, which is probably the result of a slow improvement in living conditions. The existence of birth control on the one hand, and a total fertility rate averaging six live births among the couples who do not practise contraception on the other, are other arguments against the hypothesis of a low natural fecundity in these Aymara groups.

scholarly journals Variations in reproductive events across life: a pooled analysis of data from 505 147 women across 10 countries

2019 ◽  
Vol 34 (5) ◽  
pp. 881-893 ◽  
Author(s):  
Keyword(s):  
Age At Menarche ◽  
Age At First Birth ◽  
First Birth ◽  
Natural Menopause ◽  
Individual Level ◽  
Level Data ◽  
Education Levels ◽  
Reproductive Events ◽  
Racial Ethnic ◽  
Reproductive Indices

Abstract STUDY QUESTION How has the timing of women’s reproductive events (including ages at menarche, first birth, and natural menopause, and the number of children) changed across birth years, racial/ethnic groups and educational levels? SUMMARY ANSWER Women who were born in recent generations (1970–84 vs before 1930) or those who with higher education levels had menarche a year earlier, experienced a higher prevalence of nulliparity and had their first child at a later age. WHAT IS KNOWN ALREADY The timing of key reproductive events, such as menarche and menopause, is not only indicative of current health status but is linked to the risk of adverse hormone-related health outcomes in later life. Variations of reproductive indices across different birth years, race/ethnicity and socioeconomic positions have not been described comprehensively. STUDY DESIGN, SIZE, DURATION Individual-level data from 23 observational studies that contributed to the International Collaboration for a Life Course Approach to Reproductive Health and Chronic Disease Events (InterLACE) consortium were included. PARTICIPANTS/MATERIALS, SETTING, METHODS Altogether 505 147 women were included. Overall estimates for reproductive indices were obtained using a two-stage process: individual-level data from each study were analysed separately using generalised linear models. These estimates were then combined using random-effects meta-analyses. MAIN RESULTS AND THE ROLE OF CHANCE Mean ages were 12.9 years at menarche, 25.7 years at first birth, and 50.5 years at natural menopause, with significant between-study heterogeneity (I2 > 99%). A linear trend was observed across birth year for mean age at menarche, with women born from 1970 to 1984 having menarche one year earlier (12.6 years) than women born before 1930 (13.5 years) (P for trend = 0.0014). The prevalence of nulliparity rose progressively from 14% of women born from 1940–49 to 22% of women born 1970–84 (P = 0.003); similarly, the mean age at first birth rose from 24.8 to 27.3 years (P = 0.0016). Women with higher education levels had fewer children, later first birth, and later menopause than women with lower education levels. After adjusting for birth year and education level, substantial variation was present for all reproductive events across racial/ethnic/regional groups (all P values < 0.005). LIMITATIONS, REASONS FOR CAUTION Variations of study design, data collection methods, and sample selection across studies, as well as retrospectively reported age at menarche, age at first birth may cause some bias. WIDER IMPLICATIONS OF THE FINDINGS This global consortium study found robust evidence on variations in reproductive indices for women born in the 20th century that appear to have both biological and social origins. STUDY FUNDING/COMPETING INTEREST(S) InterLACE project is funded by the Australian National Health and Medical Research Council project grant (APP1027196). GDM is supported by the Australian National Health and Medical Research Council Principal Research Fellowship (APP1121844).

Selected determinants of fertility in vietnam: age at marriage, marriage to first birth interval and age at first birth

1993 ◽  
Vol 25 (3) ◽  
pp. 303-310 ◽  
Author(s):  
Nguyen Luc ◽  
Nguyen Minh Thang ◽  
Ingrid Swenson ◽  
Pham Bich San
Keyword(s):  
Secondary Education ◽  
Rural Women ◽  
Rural Areas ◽  
Urban Women ◽  
Age At First Birth ◽  
The South ◽  
First Birth ◽  
Birth Intervals ◽  
Age At Marriage ◽  
The North

SummaryData from the 4172 women aged 15–49 interviewed in the 1988 Vietnamese Demographic and Health Survey were used to examine age at marriage, marriage to first birth intervals and age at first birth. Differences between urban and rural areas, northern and southern provinces and by education of the women were analysed.The majority of the women had their first birth before age 20, but women with secondary education had a significantly higher age at first birth than those with little or no education, and women from the north had a significantly higher age at first birth than women from the south. Rural women and those with little or no education married at significantly younger ages than urban women and those with secondary education; these education effects were confirmed in a rural subsample of women. Women from rural areas and from the north had significantly shorter marriage to first birth intervals than urban women and those from the south, but there were no significant effects related to education.

scholarly journals Continuity of maternal healthcare services utilisation in Indonesia: analysis of determinants from the Indonesia Demographic and Health Survey

2021 ◽  
Vol 9 (4) ◽  
pp. e001389
Author(s):  
Helen Andriani ◽  
Salma Dhiya Rachmadani ◽  
Valencia Natasha ◽  
Adila Saptari
Keyword(s):  
Health Survey ◽  
Employment Status ◽  
Quality Care ◽  
Community Empowerment ◽  
Health Facilities ◽  
Demographic And Health Survey ◽  
Age At First Birth ◽  
First Birth ◽  
Level Of Education ◽  
Live Births

ObjectiveWHO recommends that every pregnant woman and newborn receive quality care throughout the pregnancy, delivery and postnatal periods. However, Maternal Mortality Ratio in Indonesia for 2015 reached 305 per 100 000 live births, which exceeds the target of Sustainable Development Goals (<70 per 100 000 live births). Receiving at least four times antenatal care (ANC4+) and skilled birth attendant (SBA) during childbirth is crucial for preventing maternal and neonatal deaths. The study aims to assess the determinants of ANC4 +and SBA independently, evaluate the distribution of utilisation of ANC4 + and SBA services, and further investigate the associations of two levels of continuity of services utilisation in IndonesiaDesignData from the Indonesia Demographic and Health Survey, a cross-sectional and large-scale national survey conducted in 2017 were used.SettingThis study was set in Indonesia.ParticipantsThe study involved ever-married women of reproductive age (15–49 years) and had given birth in the last 5 years prior to the survey (n=15 288). The dependent variables are the use of ANC4 + and SBA. Individual, family and community factors, such as age, age at first birth, level of education, employment status, parity, autonomy in healthcare decision-making, level of education, employment status of spouses, household income, mass media consumption residence and distance from health facilities were also measured.ResultsResults showed that 11 632 (76.1%) women received ANC4 + and SBA during childbirth. Multivariate analysis revealed that age, age at first birth, and parity have a statistically significant association with continuity of services utilisation. The odds of using continuity of services were higher among women older than 34 years (adjusted OR (aOR) 1.54; 95% CI 1.31 to 1.80) compared with women aged 15–24 years. Women with a favourable distance from health facilities were more likely to receive continuity of services utilisation (aOR 1.39; 95% CI 1.24 to 1.57).ConclusionsThe continuity of services utilisation is associated with age, reproductive status, family influence and accessibility-related factors. Findings demonstrated the importance of enhancing early reproductive health education for men and women. The health system reinforcement, community empowerment and multisectoral engagement enhance accessibility to health facilities, reduce financial and geographical barriers, and produce strong quality care.

scholarly journals Changes in the reproduction of Vojvodina population

2006 ◽  
pp. 197-206
Author(s):  
Mirjana Devedzic
Keyword(s):  
Economic Situation ◽  
Age At First Birth ◽  
Fertility Rates ◽  
First Birth ◽  
Live Births ◽  
Cohort Fertility

Important changes in the reproduction of Vojvodina population happened in the second half of XX century. In the end of the century, the society was ruined. A large inflow of refugees in that period, as well as a social and economic situation inappropriate for making birthgiving decisions, raised the questions like how such conditions have influenced the fertility in the population, and whether the trends have continued. This paper analyzes several fertility indicators in Vojvodina over the last five decades focusing especially on the 1990s and early 2000s, in order to explain the major tendencies and the intensity of changes. It shows changes in the number of live births, specific fertility rates, total fertility rates, cohort fertility, woman?s age at first birth, and divorce frequency.

scholarly journals The relationships between women’s reproductive factors: a Mendelian randomization analysis

2021 ◽  
Author(s):  
Claire Prince ◽  
Gemma C Sharp ◽  
Laura D Howe ◽  
Abigail Fraser ◽  
Rebecca C Richmond
Keyword(s):  
Mendelian Randomization ◽  
Reproductive Factors ◽  
Sexual Partners ◽  
Age At Menarche ◽  
Age At First Birth ◽  
First Birth ◽  
Age At Menopause ◽  
Lifetime Number ◽  
Number Of Sexual Partners ◽  
Number Of Births

AbstractBackgroundWomen’s reproductive factors include their age at menarche and menopause, the age at which they start and stop having children, and the number of children they have. Studies that have linked these factors with disease risk have largely investigated individual reproductive factors and have not considered the genetic correlation and total interplay that may occur between them. This study aimed to investigate the nature of the relationships between eight female reproductive factors.MethodsWe used data from the UK Biobank and genetic consortia with data available for the following reproductive factors: age at menarche, age at menopause, age at first birth, age at last birth, number of births, being parous, age at first sex and lifetime number of sexual partners. Linkage disequilibrium score regression (LDSC) was performed to investigate the genetic correlation between reproductive factors. We then applied Mendelian randomization (MR) methods to estimate the causal relationships between these factors. Sensitivity analyses were used to investigate directionality of the effects, test for evidence of pleiotropy and account for sample overlap.ResultsLDSC indicated that most reproductive factors are genetically correlated (rg range: |0.06 – 0.94|), though there was little evidence for genetic correlations between lifetime number of sexual partners and age at last birth, number of births and ever being parous (rg < 0.01). MR revealed potential causal relationships between many reproductive factors, including later age at menarche (1 SD increase) leading to a later age at first sexual intercourse (Beta (B)=0.09 SD, 95% confidence intervals (CI)=0.06,0.11), age at first birth (B=0.07 SD, CI=0.04,0.10), age at last birth (B=0.06 SD, CI=0.04,0.09) and age at menopause (B=0.06 SD, CI=0.03,0.10). Later age at first birth was found to lead to a later age at menopause (B=0.21 SD, CI=0.13,0.29), age at last birth (B=0.72 SD, CI=0.67,0.77) and a lower number of births (B=-0.38 SD, CI=-0.44,-0.32).ConclusionThis study presents evidence that women’s reproductive factors are genetically correlated and causally related. Future studies examining the health sequelae of reproductive factors should consider a woman’s entire reproductive history, including the causal interplay between reproductive factors.

scholarly journals Age at Menarche, Age at Natural Menopause and Risk of Rheumatoid Arthritis – A Mendelian Randomization Study

2020 ◽  
Author(s):  
Jingjing Zhu ◽  
Zheng Niu ◽  
Lars Alfredsson ◽  
Lars Klareskog ◽  
Leonid Padyukov ◽  
...  
Keyword(s):  
Rheumatoid Arthritis ◽  
Mendelian Randomization ◽  
Reproductive Factors ◽  
European Ancestry ◽  
Age At Menarche ◽  
Age At First Birth ◽  
First Birth ◽  
Natural Menopause ◽  
Menarche Age ◽  
Mr Study

Abstract Background Hormonal reproductive factors have been suggested to play an important role in the etiology of rheumatoid arthritis (RA), an autoimmune inflammatory disorder affecting primarily women. We conducted a two-sample Mendelian randomization (MR) study examining three relevant exposures, age at menarche (AAM), age at natural menopause (ANM) and age at first birth (AFB), with the risk of RA.Methods We collected summary statistics from the hitherto largest GWAS conducted in AAM (N=329,345), ANM (N=69,360), AFB (N=251,151) and RA (Ncase=14,361 and Ncontrol=43,923), all of European ancestry. We constructed strong instruments using hundreds of exposure-associated genetic variants and estimated causal relationship through different MR approaches including an inverse-variance weighted method, an MR-Egger regression and a weighted-median method. We conducted a multivariable MR to control for pleiotropic effect acting in particular through obesity and socioeconomic status. We also performed important sensitivity analyses to verify model assumptions.Results We did not find any evidence in support for a causal association between genetically predicted reproductive factors and risk of RA (ORAAM=1.06 [0.98-1.15], ORANM=1.05 [0.98-1.11], ORAFB=0.85 [0.65-1.10]). Results remained consistent after removing palindromic SNPs (ORAAM=1.06 [0.97-1.15], ORANM=1.05 [0.98-1.13], ORAFB=0.81 [0.61-1.07]) or excluding SNPs associated with potential confounding traits (ORAAM=1.03 [0.94-1.12], ORANM=1.04 [0.95-1.14]). No outlying instrument was identified through the leave-one-out analysis.Conclusions Our MR study does not convincingly support a casual effect of reproductive factors, as reflected by age at menarche, age at menopause and age at first birth, on the development of RA. Despite the largely augmented set of instruments we used, these instruments only explained a modest proportion of phenotypic variance of exposures. Our knowledge regarding this topic is still insufficient and future studies with larger sample size should be designed to replicate or dispute our findings.

A PROSPECTIVE STUDY OF AGE AT MENARCHE, PARITY, AGE AT FIRST BIRTH, AND CORONARY HEART DISEASE IN WOMEN

1987 ◽  
Vol 126 (5) ◽  
pp. 861-870 ◽  
Author(s):  
GRAHAM A. COLDITZ ◽  
WALTER C. WILLETT ◽  
MEIR J. STAMPFER ◽  
BERNARD ROSNER ◽  
FRANK E. SPEIZER ◽  
...  
Keyword(s):  
Coronary Heart Disease ◽  
Heart Disease ◽  
Prospective Study ◽  
Age At Menarche ◽  
Age At First Birth ◽  
First Birth ◽  
A Prospective Study

scholarly journals Associations of Pregnancy History with BMI and Weight Gain in 45–54-Year-Old Women

2019 ◽  
Vol 4 (1) ◽  
Author(s):  
Diana C Pacyga ◽  
Melissa Henning ◽  
Catheryne Chiang ◽  
Rebecca L Smith ◽  
Jodi A Flaws ◽  
...  
Keyword(s):  
Menopausal Status ◽  
Health Study ◽  
Age At First Birth ◽  
First Birth ◽  
Critical Determinant ◽  
Lower Odds ◽  
Logistic Regression Models ◽  
Younger Women ◽  
Live Births ◽  
Pregnancy History

ABSTRACT Background Midlife women have a higher risk of cardiometabolic disease than younger women, but the lifelong biological/lifestyle factors responsible for this increase are unclear. Objectives We investigated whether pregnancy history is a risk factor for midlife overweight/obesity and evaluated potential hormonal mechanisms. Methods The Baltimore Midlife Women's Health Study, a prospective cohort, recruited 772 women aged 45–54 y. Women reported pregnancy characteristics via questionnaires, trained staff measured weight/height to calculate midlife BMI, and serum hormones were assessed by ELISA. Logistic regression models assessed associations of pregnancy history with risk of midlife overweight/obesity and BMI gain since age 18. We additionally explored whether associations differed by menopausal status, and whether midlife hormones mediated relationships of pregnancy history and midlife BMI. Results These premenopausal or perimenopausal women were 66% Caucasian/White and 30% African American/Black, with a median of 2 live births (range: 0–11) and median age at first birth of 27 y (range: 12–46 y). Women with 0 and ≥2 live births had lower odds of overweight/obesity than those with 1 birth (OR = 0.47; 95% CI: 0.23, 0.96; P = 0.04, and OR = 0.58; 95% CI: 0.35, 0.95; P = 0.03, respectively). Women with ≥2 live births also had lower odds of BMI gain than those with 1 birth (OR = 0.66; 95% CI: 0.41, 1.06; P = 0.08). Furthermore, women who were older at their first birth had lower odds of overweight/obesity (OR = 0.96; 95% CI: 0.92, 1.00; P = 0.03) and BMI gain (OR = 0.97; 95% CI: 0.93, 1.00; P = 0.06). Number of pregnancies and age at last pregnancy were not associated with midlife overweight/obesity or BMI gain. Associations did not differ by menopausal status and were not explained by midlife hormones. Conclusions Earlier childbirth and having 1 child increased women's risk of midlife overweight/obesity and BMI gain since age 18. Additional studies should focus on women's childbearing years as a critical determinant of midlife metabolic health.

scholarly journals Reproductive characteristics are associated with gene-specific promoter methylation status in breast cancer

BMC Cancer ◽  
2019 ◽  
Vol 19 (1) ◽  
Author(s):  
Lauren E. McCullough ◽  
Lindsay J. Collin ◽  
Kathleen Conway ◽  
Alexandra J. White ◽  
Yoon Hee Cho ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Promoter Methylation ◽  
Tumor Tissue ◽  
Methylation Status ◽  
Reproductive Factors ◽  
Gene Promoter ◽  
Age At Menarche ◽  
Age At First Birth ◽  
First Birth ◽  
Reproductive Characteristics

Abstract Background Reproductive characteristics are well-established risk factors for breast cancer, but the underlying mechanisms are not fully resolved. We hypothesized that altered DNA methylation, measured in tumor tissue, could act in concert with reproductive factors to impact breast carcinogenesis. Methods Among a population-based sample of women newly diagnosed with first primary breast cancer, reproductive history was assessed using a life-course calendar approach in an interviewer-administered questionnaire. Methylation-specific polymerase chain reaction and Methyl Light assays were used to assess gene promotor methylation status (methylated vs. unmethylated) for 13 breast cancer-related genes in archived breast tumor tissue. We used case-case unconditional logistic regression to estimate adjusted odds ratios (ORs) and 95% confidence intervals (CIs) for associations with age at menarche and parity (among 855 women), and age at first birth and lactation (among a subset of 736 parous women) in association with methylation status. Results Age at first birth > 27 years, compared with < 23 years, was associated with lower odds of methylation of CDH1 (OR = 0.44, 95% CI = 0.20–0.99) and TWIST1 (OR = 0.48, 95% CI = 0.28–0.82), and higher odds of methylation of BRCA1 (OR = 1.63, 95% CI = 1.14–2.35). Any vs. no lactation was associated with higher odds of methylation of the PGR gene promoter (OR = 1.59, 95% CI = 1.01–2.49). No associations were noted for parity and methylation in any of the genes assayed. Conclusions Our findings indicate that age at first birth, lactation and, perhaps age at menarche, are associated with gene promoter methylation in breast cancer, and should be confirmed in larger studies with robust gene coverage.

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