The female and male offspring of lesbian parents were significantly more to likely to report same-sex attraction, sexual minority identity, and same-sex experience

Sexual Attraction, Sexual Identity, and Same-Sex Sexual Experiences of Adult Offspring in the U.S. National Longitudinal Lesbian Family Study. Nanette Gartrell, Henny Bos, Audrey Koh. Archives of Sexual Behavior, March 19 2019, https://link.springer.com/article/10.1007/s10508-019-1434-5

Abstract: The U.S. National Longitudinal Lesbian Family Study has followed offspring with sexual minority parents from conception into adulthood. It was initiated in 1986, and it has a 92% retention rate to date. In the current investigation, the 25-year-old offspring answered questions about sexual attraction, sexual identity, and sexual experiences; their responses were compared with those of same-age adults from a population-based survey. The analytic samples consisted of 76 offspring of lesbian parents and 76 demographically matched participants from the National Survey of Family Growth. All 152 respondents were 25 years old, 48.7% were female, 90.8% identified as White, 9.2% were people of color, and all had attended at least some college. Although most respondents in each sample identified as “heterosexual or straight,” compared to their matched counterparts in the population-based survey, the female and male offspring of lesbian parents were significantly more to likely to report same-sex attraction, sexual minority identity, and same-sex experience. These findings suggest that adult offspring from planned lesbian families may be more likely than their peers to demonstrate diversity in sexual attraction, identity, and expression.

Keywords: U.S. National Longitudinal Lesbian Family Study Adult offspring Sexual attraction Sexual orientation identity Same-sex sexual experiences Sexual minorities

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Introduction
Approximately six million children and adults in the U.S. have a lesbian, gay, bisexual (LGB), or transgender parent (Gates & The Williams Institute UCLA School of Law, 2013). Although research has shown that the psychological health of adults is unrelated to the sexual identity of their parents (Gartrell, Bos, & Koh, 2018; Golombok & Badger, 2010; Golombok & Tasker, 1996; Tasker & Golombok, 1995), data on the sexual attractions, orientations, and experiences of adults who were born into sexual minority parent families are limited (Golombok & Badger, 2010). The U.S. National Longitudinal Lesbian Family Study (NLLFS)—the largest, longest-running, prospective study of planned lesbian families—provides a unique opportunity to assess the sexuality of these adult offspring (Gartrell et al., 2018; Gartrell, Bos, & Goldberg, 2011, 2012). In the 1970s, lesbian mothers who came out in the context of heterosexual relationships began to seek legal custody of their children during divorce proceedings (Hunter & Polikoff, 1976). Custody was often denied based on the assumption that lesbian mothers could influence the gender or sexual identity of their children (Golombok, 2015). The ensuing half century brought increased public acceptance and legal recognition of LGB people and parentage. Research revealed that the children of sexual minority parents were comparable in gender development to those raised by heterosexual parents, at the same time that non-traditional gender role behavior became more widely embraced (Golombok, 2015). Studies have also found that female and male sexual minorities have some notable differences: Females are more likely to identify as bisexual than exclusively lesbian, whereas males are more likely identify as exclusively gay (Savin-Williams & Vrangalova, 2013). In addition, females are more likely to fluctuate in their identities, attractions, and behavior over time (Diamond, 2007a, 2008; Diamond, Dickenson, & Blair, 2017; Johns, Zimmerman, & Bauermeister, 2013). Theories on the origins of sexual attraction, orientation, and behavior are that a variety of factors—hormonal, genetic, nonsocial environmental (e.g., in utero influences), and social environmental (e.g., social learning and cognitive behavioral)— may play a role (cf. Bailey et al., 2016, for a review). Among possible hormonal influences, prenatal androgen levels have been shown to be linked with adult gender and sexual identity (Hines, 2010, 2011). For example, adult females with congenital adrenal hyperplasia who were exposed to unusually high levels of androgens in utero are more likely to identify as male, and less likely to identify as heterosexual, than females without overexposure to fetal androgen (Hines 2010). Also, there is evidence that prenatal androgens affect the ratio of index to ring finger length, and that gynephilic women demonstrate ratios more frequently found in males (Grimbos, Dawood, Burriss, Zucker, & Puts, 2010). Whether females who later identify as lesbian were exposed to high levels of androgens in utero is unknown; likewise, there is no information about the in utero exposures of their biological children. Other research suggests that genetic factors may be influential. In a population-based Swedish study, Långström, Rahman, Carlström, and Lichtenstein (2010) found that genetically identical monozygotic twins showed more concordance in samesex sexual behavior than did dizygotic twins or other siblings. Based on these and similar findings, it has been suggested that sexual minority parents may be more likely to produce sexual minority offspring because of shared genetics (Goldberg, 2010). The strongest evidence in support of nonsocial environmental theory is that gay men tend to have more biological older brothers than heterosexual or lesbian individuals (Blanchard & VanderLaan, 2015; Bogaert et al., 2018). This fraternal birthorder effect has been found cross-culturally. It is hypothesized to be associated with the development of maternal antibodies to the Y chromosome, and exposure of the male fetus to these antibodies in utero. However, there are no data associating a fraternal birth-order effect with the offspring of sexual minority parents. Finally, social environmental theory posits that social learning or cognitive behavior may influence the sexual identity of offspring. According to social learning theory, adults who grow up with sexual minority parents might have more expansive perspectives on gender and sexuality than those raised in heterosexual-parent families, because parents of the former are less likely to discourage them from exploring nonbinary gender identities or non-heterosexual relationships (Bos & Sandfort, 2010; Gartrell et al., 1999; Goldberg, 2007, 2010; Golombok, 2015). Sexual minority parents may also model gender nonconforming interests, dress, and behavior, thereby encouraging more fluidity in gendered role behavior (Goldberg, 2007, 2010; Golombok, 2015) Cognitive behavior theorists focus on the prevailing attitudes in the culture at large, noting the potential impact of growing up in environments that are accepting or rejecting of diversity in gender and sexuality (Golombok, 2015). Evidence against social environmental theories in males is the finding that genetic male infants who were surgically changed into girls at birth, and then strongly socialized as girls, continue to be gynephilic (Bailey et al., 2016). Despite a body of research on sexual minority parent families (Bos & Sandfort, 2010; Gartrell et al., 2011; Goldberg & Gartrell, 2014; Golombok, 2015; Green, Mandel, Hotvedt, Gray, & Smith, 1986), relatively few investigations have focused specifically on the sexuality of adult offspring who were raised in these family forms. In 1991–1992, Tasker and Golombok (1995) and Golombok and Tasker (1996) carried out the second phase of a longitudinal convenience sample study on post-divorce lesbian mother families in the UK that began when the children—conceived in heterosexual relationships—were, on average, 9.5 years old. When the average age of these offspring was 23.5 years, the researchers interviewed 25 with lesbian mothers and 21 with single heterosexual mothers. Psychological well-being was not associated with family type. There were also no differences by family type in the proportions of offspring who reported same-sex attraction, identified as lesbian/gay/bisexual, or indicated on the Kinsey scale that they were not exclusively heterosexual. The only sexual minorities among the offspring were two lesbian daughters of lesbian mothers. None of those who reported sexual attraction to both females and males identified as bisexual. The offspring of lesbian mothers were significantly more likely to have to have had same-sex sexual contact, and to have considered the possibility of same-sex attraction or a same-sex sexual relationship. Using the Wave I dataset (1994–1995; students in grades 7 through 12) of the U.S. National Longitudinal Study of Adolescent to Adult Health (Add Health), Wainright, Russell, and Patterson (2004) compared psychosocial adjustment, school outcomes, and romantic relationships in 44 adolescents from same-sex parent households with a demographically matched sample of 44 adolescents from different-sex parent households. Analyses revealed no differences in the personal, family, or school adjustment of the 12- to 18-yearolds based on family type. Additionally, no significant differences in the two samples were found in the percentages of adolescents who had engaged in sexual intercourse or had a recent romantic relationship. The Add Health data use stipulations did not permit a comparison of same-sex attractions or same-sex romantic relationships because too few adolescents reported such experiences. In addition, no information was available about the parents’ sexual identity, their methods of child conception, or the duration of time that the adolescents lived in a same-sex parent household. In 2005, Goldberg (2007) surveyed a convenience sample of adults with lesbian/gay/bisexual parents, most of whom lived in the U.S. This qualitative study involved semi-structured telephone interviews with 46 adults—36 women and 10 men—ranging in age from 19 to 50 (M = 30). Most participants grew up with lesbian or bisexual mothers, though their paths to motherhood (biological, adoption, or fostering) were not specified. Nearly all of those with gay fathers had never lived with them, but saw them regularly. Almost a third of participants viewed sexuality as fluid and dynamic—existing on a continuum—rather than as a binary construct. They also felt that their parents helped them to have more flexible ideas about sexuality and gender. Some participants indicated that having a sexual minority parent led them to question their own sexuality, to think deeply about binary constructs, and to view the process of sexual exploration as normative. Bos and Sandfort (2010) examined psychosocial adjustment, gender identity, and anticipated future heterosexual romantic involvement in 8- to 12-year-old offspring of lesbian and heterosexual parents. This investigation was the second phase of a Dutch longitudinal study in which planned lesbian families were recruited through community outreach and a fertility clinic. Comparing the 63 offspring of lesbian parents with 68 offspring of heterosexual parents revealed no differences in psychosocial adjustment. However, the offspring of lesbian parents felt less compelled to conform to gender stereotypes, were less likely to view their own gender as superior, and were more uncertain about the prospect of future heterosexual romance. Golombok and Badger (2010) conducted the only comparative study of young adults from planned lesbian families that contained questions on sexuality. A volunteer sample of 18 offspring from lesbian mother families was compared with 20 from single heterosexual mother families and 32 from two-parent heterosexual families. This was the third phase in a longitudinal study of fatherless, female-headed UK families that began when the offspring were, on average, 6 years old. At Phase III, the average ages of the offspring in the three family types ranged from 18 to 19.5 years. Reported differences were that the offspring in female-headed homes had more positive family relationships, demonstrated greater psychological well-being, and were more likely to have begun dating than those from heterosexual-parent families. Only one female with lesbian parents identified as bisexual, and all remaining offspring identified as heterosexual. The U.S. National Longitudinal Lesbian Family Study (NLLFS) began in 1986 with a goal of prospectively following a cohort of planned lesbian families in which the offspring were among the first generation conceived through donor insemination by lesbian-identified women (Gartrell et al., 1996). When compared with peers in representative samples, the NLLFS offspring fared as well, or better, in psychological adjustment and quality of life (Gartrell & Bos, 2010; Gartrell et al., 2018; van Gelderen, Bos, Gartrell, Hermanns, & Perrin, 2012). Data on the sexuality of the NLLFS offspring were first collected during the fifth wave, when they were 17 years old. The offspring reported on sexual identity, and same- and different-sex sexual contact. On the Kinsey scale, 48.6% of the adolescent girls and 21.6% of the adolescent boys indicated that they were not exclusively heterosexual (Gartrell et al., 2011). Of the girls, 15.4% acknowledged same-sex sexual experiences, as did 5.6% of the boys. However, when compared with an age- and gender-matched sample from the 2006–2008 National Survey of Family Growth (NSFG), the NLLFS adolescents were no more likely than the NSFG adolescents to have had these experiences (Gartrell et al., 2012). The first generation of offspring who were conceived by lesbian mothers through donor insemination has now entered adulthood in substantial numbers (Goldberg, Conron, & The Williams Institute UCLA School of Law, 2018; Golombok, 2015). Genetic and social environmental theories predict that these offspring might be more likely than their peers to identify as sexual minorities and to report same-sex attractions, yet no comparative study to date, including the fifth wave of the NLLFS, found this to be the case. The sixth wave of the NLLFS provides a unique opportunity to assess the sexuality of these offspring as adults (Gartrell et al., 2011, 2012, 2018). At 25 years of age, the NLLFS offspring were older than participants in the two prior comparative studies of sexuality in offspring from planned lesbian families (Gartrell et al., 2011; Golombok & Badger, 2010). Also, there is evidence that sexual identity stabilizes at a later age among mostly heterosexual individuals (Calzo, Masyn, Austin, Jun, & Corliss, 2017). Moreover, the NLLFS has the largest sample size of any ongoing longitudinal study on planned sexual minority parent families. The NSFG is an ongoing population-based study focusing on the health and family life of noninstitutionalized adolescents and adults in the U.S. (Centers for Disease Control and Prevention, 2016). In assessing the well-being and sexuality of the NLLFS offspring (Gartrell & Bos, 2010; Gartrell et al., 2011, 2012, 2018), nationally representative databases such as the NSFG have been used because the recruitment criteria for these surveys are unrelated to parental sexual identity, thus minimizing potential sampling bias. The 2013–2015 NSFG was chosen for the present investigation because a subset of participants was the same age as the NLLFS adult offspring at the time of data collection. In addition, the NSFG survey contained questions pertaining to sexual attraction, identity, and behavior that could be selected and administered to the 25-year-old NLLFS offspring. The aim of the current study was to compare the responses of NLLFS adult offspring with those of NSFG participants on sexual attraction, sexual identity, and same-sex sexual experience.