Attachment in lesbian and gay parent families: a systematic review, theoretical advancements, and a 10-year research agenda.

Attachment theory was built on heterosexual, biologically related mother-infant dyads, leaving caregiving in sexual minority parent families peripheral to the field. This PRISMA 2020 systematic review synthesized empirical work applying attachment measures to lesbian mother and gay father families. Searches of PsycINFO, PubMed, Scopus, and Web of Science from inception to 28 February 2026 yielded 15 reports (8 cross-sectional, 6 longitudinal, 1 case study; from 12 studies) sampling families formed via donor insemination, gestational surrogacy, and adoption. Across measures, designs, and developmental periods, children of lesbian and gay parents did not differ from peers in attachment security or classification distributions; in adoptive gay father families, security exceeded comparison samples. Intergenerational transmission from parental coherence of mind to sensitive caregiving and child security operated as expected, regardless of within-couple biological relatedness. Caregiving role, reflective functioning, and minority stress were key moderators. This systematic review proposes five theoretical advancements and a 10-year research agenda.