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spaceDeardorff J, Ekwaru JP, Kushi LH, Ellis BJ, Greenspan LC, Mirabedi A, Landaverde EG, Hiatt RA. (2010) Father Absence, Body Mass Index, and Pubertal Timing in Girls: Differential Effects by Family Income and Ethnicity. J Adol Health

Article summary

Background: Many studies show links between father absence in the family and girls’ starting puberty at an early age. However, most research has focused on events that took place in the past, the age of first menstruation, and did not account for Body Mass Index (body weight and height), ethnicity and income. This study resolves these scientific gaps.

Study Design: This was a study of 444 6-8-year-old girls and their caregivers (96% of the caregivers were mothers) following the girls as they grow up and experience puberty. Data were collected every year in clinic, including weight, height and Tanner stage for breast and pubic hair. Caregivers reported on whether the girl’s biological father was living in the home and demographic information such as the girl’s age, race, ethnicity, household income, etc. This report focuses on the assessment of father absence at the first clinic appointment and two years of follow-up appointments for markers indicating the start of puberty. Cox proportional hazards regression models were used to test whether father absence at the first clinic appointment predicted the start of puberty by the second clinic appointment. Body Mass Index (body weight and height) was assumed to affect when girls started puberty. Differences by ethnicity and income were examined. Ethnicities included non-Hispanic white, African-American or black, Hispanic or Latino, Asian-American or other. Higher income families were defined as households with an annual income of $50,000 or more and lower income families were defined as households with an annual income of less than $50,000.

Results: Father absence was highest among African Americans and lowest among non-Hispanic Whites. Mother’s age of first menstruation was not related to the age her daughter started puberty. The rate of developing pubic hair was much higher in African American girls compared to non-African Americans. Body Mass Index (body height and weight) was not related to father absence. Father absence was linked to an earlier age of developing breasts only in higher-income families but not in lower-income families. African American girls in higher income families developed pubic hair at earlier ages if there was no father present in the home.

Conclusions: Among girls from higher-income but not lower-income families, father absence is linked to an earlier age that girls start puberty. This was particularly true for African Americans in terms of pubic hair development. These effects are not explained by body weight. Future research is needed to identify other ways that father absence, ethnicity and income impact the start of puberty in girls.

 

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