http://www.springerlink.com/content/al4574p6203628w0/

Childhood Family Correlates of Heterosexual and Homosexual Marriages: A National Cohort Study of Two Million Danes

Morten Frisch¹  and Anders Hviid¹

Published online: 13 October 2006

Abstract  Children who experience parental divorce are less likely to marry heterosexually than those growing up in intact families; however, little is known about other childhood factors affecting marital choices. We studied childhood correlates of first marriages (heterosexual since 1970, homosexual since 1989) in a national cohort of 2 million 18–49 year-old Danes. In multivariate analyses, persons born in the capital area were significantly less likely to marry heterosexually, but more likely to marry homosexually, than their rural-born peers. Heterosexual marriage was significantly linked to having young parents, small age differences between parents, stable parental relationships, large sibships, and late birth order. For men, homosexual marriage was associated with having older mothers, divorced parents, absent fathers, and being the youngest child. For women, maternal death during adolescence and being the only or youngest child or the only girl in the family increased the likelihood of homosexual marriage. Our study provides population-based, prospective evidence that childhood family experiences are important determinants of heterosexual and homosexual marriage decisions in adulthood.

Keywords  Heterosexuality - Homosexuality - Marriage - Cohort studies - Childhood - Denmark

New Evidence Found for Childhood Family Factors Influencing Sexual Orientation

("Childhood Family Correlates of Heterosexual and Homosexual Marriages: A National Cohort Study of Two Million Danes," by Morten Frisch and Anders Hviid, Archives of Sexual Behavior Oct 13, 2006;

A major study is about to be published in the prestigious peer-reviewed journal, Archives of Sexual Behavior, which provides striking new evidence for the influence of childhood family factors on sexual-orientation development.

The study used a population-based sample of 2,000,355 native-born Danes between the ages of 18 and 49. Denmark -- a country noted for its tolerance of a wide variety of alternative lifestyles, including homosexual partnerships -- was the first country to legalize gay marriage. The researchers assessed detailed marriage records for all Danish-born men and women marrying a same-sex partner from the years 1989 through 2001.

With access to the "virtually complete registry coverage of the entire Danish population," the study sample therefore lacked the problematic selection bias that has plagued many previous studies on sexual orientation.

Parental Influences on Sexual Orientation Development

The authors conclude: "Our study provides population-based, prospective evidence that childhood family experiences are important determinants of heterosexual and homosexual marriage decisions in adulthood."

Assuming that people who marry heterosexually are almost always heterosexual -- especially in a country where homosexuality carries little stigma, and gay marriage is legal -- and people who marry homosexually can be presumed to be homosexual, the study's findings offer intriguing evidence about family factors separating homosexual from heterosexual persons.

The following are findings from this new data:

1.       Men who marry homosexually are more likely to have been raised in a family with unstable parental relationships -- particularly, absent or unknown fathers and divorced parents.

2.       Findings on women who marry homosexually were less pronounced, but were still associated with a childhood marked by a broken family. The rates of same-sex marriage "were elevated among women who experienced maternal death during adolescence, women with short duration of parental marriage, and women with long duration of mother-absent cohabitation with father."

3.       Men and women with "unknown fathers" were significantly less likely to marry a person of the opposite sex than were their peers with known fathers.

4.       Men who experienced parental death during childhood or adolescence "had significantly lower heterosexual marriage rates than peers whose parents were both alive on their 18th birthday. The younger the age of the father's death, the lower was the likelihood of heterosexual marriage."

5.       "The shorter the duration of parental marriage, the higher was the likelihood of homosexual marriage...homosexual marriage rates were 36% and 26% higher among men and women, respectively, who experienced parental divorce after less than six years of marriage, than among peers whose parents remained married for all 18 years of childhood and adolescence."

6.       "Men whose parents divorced before their 6th birthday were 39% more likely to marry homosexually than peers from intact parental marriages."

7.       "Men whose cohabitation with both parents ended before age 18 years had significantly (55% -76%) higher rates of homosexual marriage than men who cohabited with both parents until 18 years."

8.       The mother's age was directly linked to the likelihood of homosexual marriage among men -- the older the mother, the more likely her son was to marry another man. Also, "only children" were more likely to be homosexual.

9.       Persons born in large cities were significantly more likely to marry a same-sex partner -- suggesting that cultural factors might also affect the development of sexual orientation.

"Whatever ingredients determine a person's sexual preferences and marital choices," conclude the study's authors, "our population-based study shows that parental interactions are important."