Pubertal Maturation in Female Development

H†kan Stattin, David Magnusson, Hakan Stattin

• Publisher: Routledge
• Year: 2018
• eBook ISBN: 9781317728238
• Topic: Medicine
• Subtopic: Physiology

Research on physical maturity has demonstrated conclusively that the assumption of an age-homogenous development does not always hold true. This volume presents a biosocial model focusing on the role of individual differences in biological maturation to be used as a framework for empirical studies exploring adolescent female development. The longitudinal design of the research program offers the possibilities to examine both short- and long-term consequences for individual variations in pubertal development. In the present volume, the data for these analyses consist of a broad range of biological, mental, psychological, behavioral, and social factors extending from the age of 10 to the age of 30. Some of the questions the present volume attempts to answer are:
* Are variations in the timing of pubertal development among girls related to their psychological and social life situation in the adolescent years? If so, when is the relation most prominent? In what areas is the relation most prominent? How does the relation come about?
* Do interindividual differences in physical maturation have any long-term consequences for adult life? If so, in what areas, for which girls, and through which developmental processes does pubertal development operate? The long-term consequences are a major concern addressed in considerable detail.

1
The Issue of Biological—Psychosocial Interaction

Facing the Issue

Adolescence is the phase in the life cycle that is associated with reaching sexual and social maturation, consequently designated as a biosocial stage of development (Ausubel, 1954). It has few definite demarcations (Brooks-Gunn & Petersen, 1984). At its lower end some measure of puberty can mark the entry into this period, but no more circumscribed end point can be established (English, 1957). During this period, thorough shifts occur in endocrine systems; in other bodily systems; and in emotional, cognitive, moral, social, and interpersonal development. The period is one of heightened introspection, of increased awareness of personal and physical qualifications. As a social marker of development, the period is customarily associated with a number of developmental tasks, such as acquiring an appropriate sex-role and identifying oneself as a mature member of society. During this period the person should behaviorally and emotionally establish independence from parents and achieve a sense of autonomy and individuation. New reference groups are formed, mainly through interaction and identification with peers. During this period most teenagers establish their first contacts with the opposite sex. The period is one of preparing for higher education and for a vocational career. Also, adolescence is intimately connected with achieving a stable individual identity and a view of life, ideologically and socially.

These processes operating in adolescence are complex and multifaceted, involving both childhood reminiscences and future adult behaviors. They emerge as the consequence of the interplay of biological factors, cognitive–experiential processes, feelings and motivational factors, social relations, and environmental factors, both proximal and distal. Often it is the specific constellation or pattern of factors operating in the biological, psychological, and the social domains that will determine the effectiveness of coping with transition tasks in adolescence, not isolated experiences, however strong they might seem.

Beyond the complexity of human behavior in this period, the developmental aspect adds one more factor: the factor of time. The time scale used almost exclusively in research on human growth is chronological age. As psychologists we are accustomed to the age-graded perspective, (i.e., to viewing individual behavior against the background of the behavior repertoire of same-age subjects). We count, for example, prevalence of a particular behavior on an age basis. As methodologists we are accustomed to basing our examinations on age-homogeneous samples, and the instruments we use are standardized by chronological age. The result is an assumption that subjects mature in monotonically similar ways. Thus, the interindividual differences that occur at a certain chronological age refer to the same systems' functioning in the same way across individuals. This assumption is particularly critical for individual predictions over time. In order for a variable to constitute an effective prognostic factor, or a criterion variable, at a given point in time, it must be demonstrated to be interindividually equivalent (i.e., to involve, across persons, systems that exhibit similar logical and meaningful relationships to the chronological age point at which the measure is taken; Goldstein, 1979).

Research on physical maturity has demonstrated conclusively that the assumption of an age-homoegenous development does not always hold true. Hence, chronological age cannot be used as the only meaningful reference scale for development (Goldstein, 1979; Magnusson & Allen, 1983b; Peskin, 1967; Young, 1963). The age-related perspective, which appears to posit a unitary progression through which teenagers change in similar ways across time, might well disguise the existence of quite different developmental progressions that would become evident if social transition was viewed from a maturational timing perspective. In fact, it is not uncommon nowadays to take the position that "biological age" is a central determinant for transition behavior in adolescence, in some respects, perhaps, a more sensitive index of psychosocial changes in the individual than other time-linked measures.

This volume is concerned with the maturational timing issue and particularly with the significance of pubertal development among females. We direct attention to the role of variations in the timing of biological maturation in females for progression in various areas in the adolescent life phase. The purpose is to systematically analyze, from an individual difference perspective, the psychosocial consequences that take place as an effect of entering puberty earlier or later in females. What is the significance of pubertal change in adolescence? To what extent do emotional and social adjustment during this period have a maturation basis? How are variations in the timing of pubertal maturation interwoven in the complex network of factors underlying the completion of normal developmental tasks over time? The issue before us is to explore how interindividual differences in pubertal development are linked to new social behavior and emotional reactions in adolescence and how they relate to social support systems and to self-concept. In the pursuit of an understanding of the role of physical maturation for psychosocial transition in adolescence, we propose and test, within the framework of an interactional model, various developmental progressions through adolescence that are affected by variations in pubertal timing. In summary, the dual aim of this research is to map the domains related to differential pubertal development in individuals and to attempt to map the processes operating in these domains.

This endeavour involves attempting to crystallize the primary meaningful connections between the physical growth component and behavior: to determine the configuration of change on different levels of organization and how changes in one part of the total organization are linked with changes in other parts. We are attentive to those factors in the girls' environment that are affected by their bodily development, to how significant others respond to the change in the girls, and to how the girls themselves are affected by other persons' views and behaviors directed toward them. Particular attention is paid to the mediators of the impact of biological maturation on social and emotional behavior. In the end we hope to say something more definite about which areas are and are not likely to be affected by interindividual differences in physical growth in girls, and, in particular, about how these connections are formed.

Characteristic of physical growth in adolescence is the rapidity with which it occurs and the wide range of effects it has on the body. The physical growth process is completed within a relatively short space of time. This fact does not necessarily imply that interindividual differences in physical growth lose their significance for psychosocial functioning later on. An important task before us is to examine the evidence for the possible long-term implications of timing of pubertal maturation. Given this objective, the only meaningful way in which to address the long-term consequences of variations in pubertal development for the adult life course is to follow one and the same group of subjects through adolescence to adulthood. The present investigation constitutes a prospective longitudinal analysis of Swedish females over two decades, from 1965 when they were 10 years old to the present time when they are about 30.

Some of the questions we attempt to answer are the following:

• Are variations in the timing of pubertal development among girls related to their psychological and social life situation in the adolescent years?
• If so, when is the relation most prominent?
• In what areas is the relation most prominent?
• How does this relation come about?
• Does the relation sustain over time in adolescence?
• Do interindividual differences in physical maturation have any long-term consequences for adult life? If so, in what areas, for which girls, and through which developmental processes does pubertal development operate?

The data for this analysis consist of a broad range of biological, mental, psychological, behavioral, and social factors collected for the sample of females over a considerable age span. Data are reported on the relation between biological maturity and factors connected with:

• The person herself: self-image, self-esteem, emotionality, personality constellation, etc.,
• her family: mother and father relations, family conflicts, family orientation, etc.,
• her peers: emotional relations to peers, popularity in the peer group, peer—parent preferences, characteristics of her peer network, peers as norm transmitters, etc.,
• her opposite-sex relations: popularity among boys, dating, sexual intercourse, attitudes toward sex, etc.,
• her school adjustment: school interest and aspirations, school achievement, teacher relations, school problem behaviors, etc.,
• her general social adjustment: mental problems, social deviancy, delinquency, alcohol patterns, abortions, etc.
• her adult life situation: marriage, children, level of education, work life, etc.

The scientific goal is to explain and understand if, to what extent, and why interindividual differences in pubertal development have short- and long-term impact on the life situation in various areas. Not only may such an exploration give insight into the role of timing of pubertal maturation for the development from a teenager to an adult, it could also contribute to a deeper understanding of the nature and the direction of adolescent transitions in general.

An Interactionist Approach

The abrupt changes in bodily proportions and functions accompanying puberty are a most salient change characteristic in adolescents. One enters this life phase with childish bodily proportions but leaves it with adult-like physical shape and with the capacity to reproduce. However, even though the emergence of this new pubertal force creates a sort of discontinuity in individual development, there are few reasons to believe that pubertal timing, except in some few obvious ways, has a unidirectional influence on behavior, There are even fewer reasons to assume that its influence generally should be interpreted in a casual way. As Brooks-Gunn and Petersen (1984) have pointed out, the mere fact that there exists a relationship between pubertal growth and social behavior does not imply a cause-effect relationship. What we witness might rather be the co-occurrence of different developmental factors. If so, the biological determinism model, which infers that observed changes in feelings, motivations, social relations, and so on are casaully related to changes in the physical-bodily domain, has limited applicability.

Although the point in time when puberty takes place is largely beyond the control of the individual's purposive behavior and although physical growth itself follows a more or less predetermined course once its onset occurs in individuals, pubertal development is not a process that emerges suddenly, without connection with prior aspects of the person or her social environment. Interindividual differences in pubertal timing are not determined randomly. They are connected with general cultural environmental conditions, with genetic determinants and with specific individual experiences, like health history, protein intake, and amount of daily exercise, to take a few examples. Birth order and the number of siblings have been found to be associated with age of menarche (James, 1973; Roberts & Dann, 1967; Roberts, Rozner, & Swan, 1971), such that the larger the family, the later in time does puberty occur. This relationship has been attributed to less nutritional intake per person and higher likelihood of diseases in larger families (Tanner, 1965). Malnutrition (as evidenced in anorexia nervosa), diabetes, illness, and intensive athletic activity prior to puberty have been found to delay the puberty entry. Stress, in a wide sense, can also affect the age at which the puberty sequence starts. In a Swedish longitudinal study, Miserandino (1986) reported effects of eating habits and sleeping problems at age 8 on the point in time for menarche.

Stockier-built pre-teens reach their point for menarche at an average earlier time {Adams, 1981; Bruch, 1941; Gam, 1980; Greulich, 1944; Kantero & Widholm, 1971; McNeill & Livson, 1963). It has been suggested that a "critical weight," or height/weight ratio, reflecting the percentage of body fat, determines when girls reach their menarche (Frisch & Revelle, 1970). Alternative hypotheses, associating the menarche more with skeletal maturation, have also been advanced (Ellison, 1982; Tanner, 1978). Among nonexercising females, those who reach menarche early are, on the average, heavier than those who reach menarche late; however, this heaviness is not necessarily connected with an absolute body fat standard (Garn, 1980). Among exercising females on the elite level, the amount of exercise seems to be a vital factor for when puberty occurs. Futhermore, menstrual disturbances among teenage girls are often considerably more common among hard-exercising females than among females in general. In a recent Swedish study of training patterns and menstrual disturbances among hard-exercising teenage girls (Lindahl & Bergh, 1988), girls whose menstrual cycle were totally turned off trained on an average of 477 hours per year, in comparison with 395 hours for females with irregular menstruations and 366 hours for females with normal menstruation. Only 4 out of 10 hard-training girls had regular menstrual cycles. Menstrual problems were most common among gymnasts and cross-country skiers.

Studies conducted in various cultures show rather wide differences in growth rates. More than 6 years' difference in median age at menarche was, for example, reported by Tanner (1966) for subjects from Cuba and the Bundi tribe in New Guinea. These population differences have been attributed to factors affecting the standards of living and health, such as protein intake and availability of medical facilities, and to genetic differences. Similar types of explanations have been offered for the differences in growth rate observed between subjects from urban and rural areas, with subjects from urban areas having an accelerated growth rate.

Undoubtedly, menarcheal age is under genetic influences (Garn, 1980; Hiernaux, 1972; Jensen, 1969; Kantero & Widholm, 1971; Roberts & Dann, 1967; Tanner, 1962). Studies have been performed investigating the correspondence of menarcheal age between girls and their mothers, as well as between girls and their sisters. The early developed girl tends to have an early developed mother and an early developed sister. The correlation for age at menarche between mothers and daughters has been estimated at about. 20-.25 and that between siblings at .35-.40 (Damon, Damon, Reed, & Valadian, 1969; Garn, 1980; Zacharias, Rand, &. Wurtman, 1976). Menarcheal age also has been studied for monozygotic twins, diozygotic twins, and nonrelated subjects. Tanner (1962) cited data showing correlations at the level of .70 between identical twins with regard to skeletal maturity, at around .30 between siblings and no correlation between unrelated subjects. Genetic influences also are found with respect to height and weight and height and weight gain in adolescence (Fischbein, 1977). The casual relationships involved among the various hereditary and environmental factors are, however, to a great extent still unclear. One hypothesis that has been put advanced is that growth rate, as manifested by earlier menarche, is a function primarily of environmental factors, such as nutrition, whereas the ultimate growth outcome, like adult height, is affected more by genetic determinants (see Jensen, 1969; Tanner, 1965).

Even if pubertal change were totally under the control of fundamental biological drives, its significance in females' development could not be determined without due consideration of environmental conditions. Margaret Mead's (1952) ethnological studies of adolescencs in Samoa made clear that the impact of variations in biological maturation on behavior is highly dependent on overriding cultural expectations and demands. Its consequences for the life course will depend on the societal conditions for development in their members. Many differences can be found in institutionalized and informal upbringing conditions from society to society, presumably connected with the issue on how behavior is affected by pubertal growth. For example, the concept of dating is a social phenomenon that American, but not Swedish, teenagers are quite familiar with. This fact cannot be bypassed when attempts are made to compare the effect of biological maturation in the two countries in the realm of heterosexual relations.

In addition, there are history-graded factors. The cultural impact on the relationship between biological maturation and behavior will apply to the historical era in which studies of physical growth are conducted. Findings obtained in longitudinal growth studies that started in the late 1920s and the early 1930s do not necessarily hold for today's generation of teenagers.

Societal norms, values, and customs are transformed into the real-life situations that teenagers confront, into the demands and expectations of the immediate environment. Therefore, the study of physical growth becomes the study of how physical growth is connected with the particular features of the environment in which individuals are raised. It concerns how the individual copes with her own physical and sexual maturation and how she adjusts to the demands and the expectations made on her biological development from the social and cultural environment. From the perspective of the individual girl it is a dual, reciprocal process: an adjustment to one's own physiological change, including the recognition of how this change is related to the general development toward adult status, and an adjustment to others' reaction to this change.

Because the effect of physical maturation is connected with the individual's own reaction to his or her own physical development, other significant persons' reactions to this change, the conformity to the role as early or late developer, and so on, the impact of physical maturation on the functioning of individuals in different areas is most fruitfully approached from a perspective of an integrative theoretical model involving specific outlines of the interconnection between physical, cognitive, emotional, social, and behavioral factors. In fact, there are probably very few domains of research where it is so obviously necessary to study behavioral change from the perspective of reciprocal, interactive influences as in research on the effects of physical growth. This is a challenging task, and its very challenge is perhaps one of the reasons we have recently witnessed an upsurge of interest in the study of processes accompanying pubertal change (Lerner & Foch, 1987).

Our research approach in this book can be characterized as basically a holistic and an interactionist approach (Magnusson, 1988). The fundamental outlook is that individuals function as total integrated organisms. Developmerit does not take place in one single component in isolation from the rest. It contributes to the whole.

One way to illustrate what goes on in the individual over time is to use a systems metaphor. From that perspective the person can be considered as a totality or as a total system whose functioning depends on the functioning of subsystems of feelings, thoughts, attitudes, interests, behaviors. From the viewpoint of a system with interrelated parts, isolated changes are unlikely to occur. The constituent parts of the configuration are bound to each other, and the total system tends to maintain its configuration (Weiss, 1969). From another perspective, structures and processes occurring in one part of the system can be used as input for investigation of what occurs at other subsystems or systems on a more superordinate level. In Koestler's (1978) vocabulary, we deal with "holons," having one face directed toward higher order levels and one face toward lower order levels. A model for development that investigates maturation from one particular viewpoint is not "better" or more "true" than another model specifying the developmental parameters from another viewpoint. On the contrary, they approach one and the same phenomenon from different angles. Ultimately, the thorough understanding of an element in development involves taking into account the relevant factors operating on superordinate and subordinate levels as well as those functioning on the same organiz...

Table of contents

• Cover
• Half Title
• Title
• Copyright
• Contents
• Preface
• Chapter 1 The Issue of Biological–Psychosocial Interaction
• Chapter 2 The General Approach and the Basic Model
• Chapter 3 Data
• Chapter 4 Psychological Adaptation and Self-Concept
• Chapter 5 Interpersonal Relations
• Chapter 6 Social and Emotional Adjustment
• Chapter 7 The Short-Term Consequences
• Chapter 8 Developing Girls in a Developing Environment
• Chapter 9 Mediators of the Influence of Pubertal Timing
• Chapter 10 The Long-Term Consequences
• Chapter 11 Some Final Reflections
• References
• Author Index
• Subject Index