Changes in sport and physical activity participation for adolescent females: a longitudinal study.

BACKGROUND: Participation in sport and physical activity is reported to decline during adolescence, particularly for females. However we do not have a clear understanding of changes in the context (i.e., modes and settings) of participation throughout adolescence. This study investigated longitudinal changes in physical activity participation and the specific modes and settings of physical activity, together with cross-sectional comparisons, for two age cohorts of female adolescents. METHODS: Survey of 729 adolescent girls (489 recruited in Year 7 and 243 in Year 11). Participation in eight different modes/settings was reported. PA was measured using 24-h recall diary and metabolic equivalent weighted energy expenditure (MET-min) in Leisure Time Moderate and Vigorous Physical Activity (LTMVPA) on the previous day was calculated. RESULTS: There were no significant changes in duration or total MET-min of LTMVPA on previous day. However, there were significant changes in the modes/settings of participation across time. Participation in school physical education rose during early adolescence before decreasing significantly, and participation in competitive sport and club sport significantly decreased over time; however there were increases in non-competitive forms of physical activity. CONCLUSIONS: Overall levels of physical activity did not significantly decrease over adolescence, which is positive for physical health. However, the transition from structured sport to non-organised physical activity may effect social and psychological health, which needs to be further examined.

Socioecological factors potentially associated with participation in physical activity and sport: A longitudinal study of adolescent girls.

OBJECTIVES: Many adolescents are not physically active enough to receive associated health benefits. Furthermore, participation in physical activity generally declines during adolescence, and to a greater degree for females. Longitudinal research is required to better understand the determinants of change in physical activity by adolescent females to inform physical activity-related policy and practice. This study explored patterns of change in socioecological factors hypothesised to be associated with physical activity and sport, across the adolescent period for females. METHODS: This longitudinal study employed three annual surveys of females from metropolitan and non-metropolitan areas recruited in Year 7 (n = 328) and Year 11 (n = 112). Self-report measures included questions regarding general barriers to participation, as well as factors relating to the socioecological domains. RESULTS: The barriers where significant changes within or differences between cohorts were observed were mostly intrapersonal (lack of energy, lack of time due to other leisure activities). Lack of time was more prevalent in the Year 11 cohort than in the Year 7 cohort. Perceived importance of life priorities mainly related to education and study and more so for the Year 11 cohort. Perceived competence declined for the Year 7 cohort. Support from family and peers trended downwards in both cohorts, whereas access to facilities increased both within and between cohorts. CONCLUSIONS: Significant patterns of change in the determinants of physical activity participation were observed across the adolescent period. It is important to consider flexible structure and scheduling of physical activity and strategies to develop competency in childhood and early adolescence.

A survey of 1700 women who formed their families using donor spermatozoa.

This paper reports the results of an online survey of 1700 recipients of donor spermatozoa conducted by the Donor Sibling Registry, aiming to understand the perspectives of respondents who had used donor spermatozoa. The survey examined: choice of sperm bank and donor; reporting of births and genetic disorders; disclosure; contact with donor and half-siblings; regulation of sperm donor activity and genetic testing; and access to medical information. The respondents formed three groups: single women; women in a same-sex relationship; and women in a heterosexual relationship. Some differences between the three cohorts were observed: preinsemination counselling; acceptance of donors without medical records or with chronic or late-onset diseases; awareness of choice of bank and type of donor; and views on the right of offspring to know their genetic origins. However, important areas of common ground were identified: the wish by those who had used an anonymous donor that they had used an open-identity donor; support for, and willingness to pay for, comprehensive genetic testing of donors; and desire for access to their donor's family health information. The implications of these results for policies concerning the use and management of donor spermatozoa will be discussed. This paper reports the results of a survey of 1700 women who used donor spermatozoa to conceive a child. The survey considers their views on the following areas: choice of sperm bank and donor; reporting of births and genetic disorders; disclosure; contact with donor and half-siblings; regulation of sperm donor activity and genetic testing; and access to medical information. This was an online survey was designed and conducted by the Donor Sibling Registry (DSR), a US-based non-profit organization that supports donor sperm recipients, donors and donor-conceived people. The survey aimed to understand the experiences, perspectives and concerns of women who had used donor spermatozoa. The respondents formed three groups: single women; women in a same sex relationship; and women in a heterosexual relationship. Some differences between the three groups were observed: preinsemination counselling; acceptance of donors without medical records or with chronic or late-onset diseases; awareness of choice of bank and type of donor; and the right of offspring to know their genetic origins. However, despite these differences, important areas of common ground were identified: the wish by those who had used an anonymous donor that they had used an open-identity donor; support for, and a willingness to pay for, comprehensive genetic testing of donors; and desire for access to their donor's family health information. The implications of these results for policies concerning the use and management of donor spermatozoa will be discussed.

Understanding the contexts of adolescent female participation in sport and physical activity.

PURPOSE: Participation in physical activity (PA) is reported to decline in adolescence, particularly for girls. However, we do not know if this decline in PA is consistent across modes and settings or whether there are transfers of participation between modes and settings. Nor do we understand the changes in specific types of PA or the interaction between types of participation and different modes/settings. This study investigated contexts of PA participation for female adolescents at two life transition points. METHOD: A survey of 489 Year 7 and 243 Year 11 adolescent girls was conducted, incorporating a measure of overall PA level and participation rates in seven modes/settings and in specific types of sport and PA. RESULTS: Less than half of the respondents met or exceeded the recommended level of moderate or vigorous PA--60 min or more--on the previous day, and there was no statistically significant difference in the proportions in Years 7 and 11 (39.5% vs. 45.9%; p > .05). However, older adolescents shifted their participation away from organized, competitive modes and settings toward nonorganized and noncompetitive modes and settings and individual types of PA. CONCLUSIONS: An understanding of the changes in PA modes and settings identified here can inform the planning of policies and implementation of programs for the promotion of PA by adolescent girls.

Forming a family with sperm donation: a survey of 244 non-biological parents.

There has been little research on the views and experiences of non-biological parents of sperm donor children. This paper reports the results of a survey of non-biological mothers and fathers. An online survey was designed and conducted by the Donor Sibling Registry, a US-based non-profit organization that supports those who have used donor conception. A total of 244 people responded (199 non-biological mothers and 45 non-biological fathers). The survey aimed to understand the perspectives of the respondents who had used donor spermatozoa within heterosexual or same-sex relationships, by exploring their views on a number of key issues. Certain issues and concerns associated with not being genetically related to their offspring were experienced differently by men and women. However, there were many important areas of common ground: a concern for getting a healthy donor, the importance of matching the donor to the non-biological partner, and the amount of thought that went into selecting the donor. The implications of these results for policies concerning donor spermatozoa are discussed.

Prospective application of a five-step regulatory assessment model to a proposed federal sperm donor registry in Australia: is it in the public interest?

It has been proposed that a nationally mandated donor registry be established in Australia to provide data for estimating the possible number of inadvertent half-sibling matings resulting from the multiple use of anonymous donors in donor insemination and to assist identity-release donors and their donor-inseminated children to establish contact. A five-step regulatory assessment model, as described by Johnson and Petersen in 2008, was applied prospectively to the proposed donor registry to identify public interest issues. The resultant issues concern the public ethical interest in child welfare; the public health interest in avoiding genetic abnormalities/disease; public socio-political and legal interests in avoiding inadvertent consanguineous relationships; public ethical and health interests in avoiding identity issues in the donor-inseminated child; and public socio-ethical interests in providing nationally mandated, comprehensive records of donor insemination outcomes. These results provide a basis for further discussion in regard to donor insemination legislation at the federal level.

Sperm donor limits that control for the 'relative' risk associated with the use of open-identity donors.

The majority of countries that support the use of donor insemination (DI) in artificial reproductive technology (ART) limit the number of children born from one donor. The setting of these donor limits, though intended to control for the risk of inadvertent half-sibling unions between the offspring of anonymous donors, actually have no evidence base. Controlling for the risk of inadvertent half-sibling unions may soon become unnecessary due to the increasing world-wide use of open-identity sperm donors and the revocation of donor anonymity in many countries. With the shift from anonymous to open-identity donation, the central issue is not the risk of genetic abnormality from inadvertent half-sibling consanguinity; it is the psycho-social impact of the multiple use of open-identity sperm donors. Despite this, the jurisdictions that allow or mandate the use of open-identity donors continue to observe existing limits that do not consider nor specifically control for the psycho-social impact of the multiple use of open-identity sperm donors. It is proposed that: (i) conservative interim donor limits be placed on the multiple use of open-identity donors, while research into the psycho-social impact of disclosure is undertaken to inform the establishment of evidence-based limits; and (ii) the existing limits in jurisdictions where anonymity is still commonly practiced or protected could be raised, if an updated mathematical model was used for calculating evidence-based anonymous donor limits.

Removing the "relative" uncertainty within the Australian donor insemination network.

In Australia there is no federal legislation limiting the use of donor sperm. However, it is important to place limits on the multiple use of sperm donors to reduce the risk of inadvertent half-sibling mating between the offspring of anonymous donors and to control for the consequences of contact between identity-release donors and their donor-inseminated offspring. A nationally mandated donor registry should be established to enable, first, the calculation of updated variable values for use in the development and implementation of a predictive model to estimate the probability of half-siblings mating and provide policy-makers with empirical evidence to inform the setting of anonymous donor limits; and secondly, the linking of identity-release donors to their donor-inseminated offspring and an investigation into the psychosocial consequences of that linking so as to be able to implement suitable donor limits as well as management strategies and support systems for these new "extended families" within the donor insemination network.

Who's keeping count? The need for regulation is a relative matter.

It is important to have an accurate model for calculating limits to sperm donation so as to avoid inadvertent half-sibling mating and help protect the rights and welfare of the donor- inseminated child. The most highly developed model to date cannot be used as there is inadequate regulation of donor insemination among United States sperm banks.

A review of mathematical models used to determine sperm donor limits for infertility treatment.

OBJECTIVE: To review mathematical models used to determine sperm donor limits for infertility treatment and to consider the need to develop a new, internationally recognized and applicable model for calculating limits. DESIGN: Literature review. SETTING: Models for determining sperm donor limits were identified through bibliographic databases. PATIENT(S): Published models. INTERVENTION(S): Variables used in the models were defined, evaluated, and assessed for relevancy and applicability. MAIN OUTCOME MEASURE(S): Relevance and applicability of model variables used to predict the number of consanguineous matings, probability of unwitting sibling mating and contribution to F (coefficient of inbreeding). RESULT(S): Models found to be outdated and inadequate for the present-day. CONCLUSION(S): Many countries have introduced limits to the number of offspring each anonymous sperm donor can father but these limits vary considerably. Published models for calculating sperm donor limits are in need of improvement and it is recommended that an enhanced, internationally applicable formula be developed for calculating acceptable limits. Moreover, it is recommended that further research be undertaken into the social and familial consequences of the revocation of sperm donor anonymity and the implications for the setting of sperm donor limits.