Secular Changes in the Age of Menarche of Rural and Urban Girls from an Industrial Region of Poland in Relation to Family Structure

Purpose: The consequence of better living conditions for every subsequent generation is the phenomenon of change in the rate of maturation and body dimensions. The aim of this study was to evaluate the intergenerational changes in the age of menarche of girls living in rural and urban communities in the industrial region of Poland using samples from two different centuries and to determine the relationship between family structure (two-parent and single-parent) and sexual maturation of the girls in both environments. Methods: The study included 3643 rural and urban girls aged 7–16 from southwestern Poland (Copper Basin). The research was cross-sectional in each environment around 2000 and 2010, and it was carried out twice. Two types of family structure were taken into account: two-parent and single-parent families. The median age of menarche and odds ratio (OR) of menarche depending on the place of residence and family structure were calculated. The status quo method was used when assessing the age of menarche. Results: In both groups, the age of menarche significantly decreased during the decade. The median age of menarche in the urban girls was lower compared with their rural peers, but a significant difference was found only during the second examination (a decade after the first examination). There were no significant changes in menarche during the decade regarding family structure (neither in girls from two-parent families nor those from single-parent families), except in rural girls from two-parent families. Comparing the median age of menarche of girls from two-parent families with girls from single-parent families (urban and rural) showed lower median values in the girls from two-parent families, but no differences were significant. Conclusions: The acceleration of the maturation rate over the last decade has been observed among both rural and urban girls. Environmental differences in maturation rates between rural and urban girls increased over the course of the decade, and the difference between the rural and urban girls’ age of menarche was statistically significant in the second examination (around 2010).The living conditions related to family structure did not significantly affect the timing of menarche.

Age at menarche among rural school youth in west-central Poland: variation with weight status and population growth

Studies of age at menarche in Poland have a long history and consistently show an urban-rural gradient. The objectives of the study were to to estimate the age at menarche among school girls resident in ten rural communities of the Greater Poland province in 2016 and to compare ages at menarche by weight status and by population growth. The sample included 1146 girls, 7–16 years of age, resident in ten rural communities. Menarcheal status was obtained via interview. Heights and weights were measured; the BMI was calculated. Based on the latter, the girls were classified as thin, normal weight and overweight (including the obese) relative to IOTF criteria. Population growth between 1986 and 2016 in each community was estimated from local records. Ages at menarche were estimated with the probit regression protocol (SPSS) using the logistic model with log 10 transformation for the total sample and for the subsamples by weight status and population growth. The median age at menarche for the total sample of rural girls was 13.25±0.20 years. Menarche was earlier among Overweight (13.06±0.32 years) compared to Normal Weight (13.25±0.37 years) and Thin (13.81±0.41 years), and among girls resident in communities with Major population growth (12.58±0.44 years) compared to Little/No growth (13.65±0.14 years). Results of the present survey were generally consistent with recent surveys of age at menarche among rural girls in Poland and among girls classified by weight status. Corresponding comparative data relating menarche to population growth are lacking.

Secular trend and social gradients in the menarcheal age of girls from eastern Poland between 1986 and 2016

The age at menarche is changing together with the development of society. The intensities of secular trends vary in different countries, regions or even towns and villages. Therefore, the objective of the paper was to assess the changes of the menarcheal age of girls in groups defined by different levels of parental education and the number of children in a family as well as the general index of socioeconomic status. The paper utilises the results of research conducted in the years 1985–1986, 2005–2006 and 2015–2016, covering 11 671 girls aged 10–16 from eastern provinces of Poland. Information about the date of birth, the date of the first period, place of residence, fathers’ and mothers’ education and the number of children in a family was collected. Research material was divided into groups stratified by mother’s education, father’s education, number of children in a family, size of place of residence and the general index of socioeconomic status (SES) was calculated. The results were processed statistically using one-way analysis of variance (ANOVA) and the Newman-Keuls method.

In all the assessed groups of girls the acceleration of maturation has been observed. Greater socio-economic differences of the menarcheal age of the respondents were observed in the years 1986–2006, whereas in the years 2006–2016 the differences were smaller. During the assessed period of 30 years, the most intensive acceleration in menarche was observed in the lowest social strata, i.e. in the daughters of parents with primary or vocational education, in those from the largest families and in those who were included in the group with the lowest SES point values. The lowest acceleration in the described indicator of development was found in girls from families with one or two children, whose parents had higher education degrees and the highest SES values.

The assessed schoolgirls still demonstrate the existence of social gradients in the menarcheal age but the gradients are smaller than 30 years ago.

Does extreme maternal age still act as a risk factor for adverse perinatal outcome? Evidence from Poland 20 years after the social and economic transformation

It was examined whether positive changes in maternal SES and medical facilities in Poland 20 years after social and economic transformation weakened the role of maternal age in shaping perinatal outcome. Data comprised of 2,979 children born in 2000 and 2,992 – born in 2015. To test the differences between the frequency of indicators of adverse perinatal outcome the chi-square test was applied. The influence of maternal age on the perinatal outcome was estimated using Generalized Linear Models (GLMs), with binomial error distribution and the logit link function. The infants survival was examined using survival analysis. Gestational age and birth weight were influenced by mother’s age and the year of survey. Infants of adolescent and older mothers represented the groups with a risk of adverse perinatal outcome: an increase of preterm births and higher risk of having children with LBW in the group of adolescent mothers than in mothers aged >35, infants born SGA and LGA found in both adolescent and adult mothers. GLMs confirmed the impact of maternal age and the year of survey on perinatal outcome. The Cox proportional hazard models showed that the year of survey was the only factor affecting the risk of infants’ death. The impact of maternal age on adverse perinatal outcome can be counterbalanced by positive changes in social and economic standard of living of women, improvement in neonatal medical care and better equipment of hospital wards in 2015 as compared to 2000.

Body height and age at menarche of girls from eastern Poland in the period of political transformation

Biological state of a group of people or particular individuals in various phases of ontogenesis should be treated as a positive health measure. The aim of the study was to assess the directions of changes in body height and age at menarche of girls from eastern Poland in the years 1986-2016. The data regarding 30784 students aged 10-16 living in towns and villages of the eastern parts of such regions as Podkarpackie, Lubelskie, Podlaskie, Warminsko-mazurskie and, to a slight extent, Mazowieckie were used in the study. Body height was measured and information concerning the place of living and age at menarche (yes-no) was gathered during interviews. Acceleration of body height and age at menarche was observed in girls from the east of Poland in the period of political transformation and after European Union (EU) accession, while the level of secular trends was connected with the pace of changes in the environment. Biological effects of the EU preservation of Polish agriculture and particular care of the eastern provinces of Poland reduced developmental differences between these provinces and other regions of Poland. Moreover, in the analysed period of three decades (1986-2016), the disappearance of differences in body height and age at menarche between the inhabitants of rural and urban areas was noted, which indicates larger positive socio-economic changes in the countryside. In turn, greater body height was noted in non-menstruating girls compared to their menstruating counterparts. However, in subsequent observations, smaller differences between these groups were observed.

Secular trend and social variation in age at menarche among Polish schoolgirls before and after the political transformation

OBJECTIVES

To describe the biological results of the political and economic transformations that took place in Poland between 1966 and 2012, based on an analysis of age at menarche, and to determine changes across social groups.

METHODS

Data were collected in 1966, 1978, 1988, and 2012 in several districts of Poland. The study included 34,940 schoolgirls. Age at menarche was assessed with the use of status quo method. Definition of socioeconomic status was based on 4 factors: urbanization level, mother and father education, and family size.

RESULTS

When the political and economic situation in Poland improved, a decrease in age at menarche was observed, whereas in years of crisis it increased. The same social differentiation in menarcheal age observed before the political transformation continued to be present in 2012.

DISCUSSION

Socioeconomic changes were significantly associated with age at menarche. Social inequalities, reflected in menarcheal age, continue to be present in Poland.