The October issue of Journal of Marriage and Family published an analysis by Charles Lau of a British probability sample, “The Stability of Same-Sex Cohabitation, Different-Sex Cohabitation, and Marriage.”
Lau found that cohabiting same-sex couples in Great Britain are twice as likely to break up as cohabiting opposite sex couples — and married couples (all opposite-sex in Great Britain) are at least five times more stable than same-sex couples:
Compared to married couples, the dissolution rates for male and female same-sex cohabiters were seven and five times higher, respectively. Among cohabiters, the differences were smaller: The dissolution rate for male and female same-sex cohabiters was approximately double the rate for different-sex cohabiters.
He also reports no increase in stability of same-sex unions between the 1958 birth cohort and the 1970 birth cohort.
This of course cannot tell us how children fare on average when they are raised by stable same-sex couples, or whether gay marriage will significantly increase stability in same-sex couples. It can tell us why Professor Mark Regnerus’s study turned up so few: They are rare.