OLR Research Report

October 25, 2002 2002-R-0879


This Backgrounder provides information on (1) professional literature examining the effects of lesbian and gay parenting on children and (2) marriage and divorce rates in the United States (1940-2000) and Denmark (1989-2001, the period covered by that country's domestic partnership registration law). We include a list of further reading with hyperlinks to documents that are available online; legislators and staff can ask OLR for copies of any document listed.


The great majority of studies published in the past 20 years conclude that there are no notable developmental differences between children raised by heterosexual parents and those raised by lesbian and gay parents. Along the same lines, several medical and mental health professional associations, including the American Academy of Pediatrics, the American Psychiatric Association, the American Psychoanalytic Association, and the American Psychological Association have issued formal statements generally supporting equal access to parenting and adoption for gay men and lesbians.

A small minority maintain that being raised in a lesbian or gay household subjects children to increased risks in a number of areas, including gender and sexual identity confusion; loss of a parent to AIDS, substance abuse, or suicide; and depression and other emotional difficulties. Some also infer from studies examining the well-being of children raised by single mothers (i. e. , without fathers present in their lives) that children raised in same-sex households are more vulnerable to delinquency, substance abuse, violence and crime, teen pregnancy, dropping out of school, suicide, and poverty.

Critiques of the Studies

The reliability of the conclusions reached on both sides has come under increasing scrutiny recently, as critics challenge researchers' underlying assumptions and identify limitations in the studies' research populations, concepts, and designs. Analysts commissioned by the Marriage Law Project, an organization whose mission is to reaffirm the legal definition of marriage as the union of a man and a woman, examined 49 studies in which the researchers had concluded that there was no difference in the development of children raised in same-sex and opposite-sex households.

The analysts concluded that each study was seriously flawed in one or more of the following respects: (1) unclear hypotheses and research designs; (2) missing or inadequate comparison groups; (3) self-constructed, unreliable, and invalid measurements; (4) non-random samples, including participants who recruit other participants; (5) samples too small to yield meaningful results; or (6) missing or inadequate statistical analysis (Lerner and Nagai, "No Basis: What the Studies Don't Tell Us About Same-Sex Parenting" (Marriage Law Project, 2000)). Other critics suggest that study results are affected by the researchers' ideological bias in favor of equal rights for gay men and lesbians (Wardle, "The Potential Impact of Homosexual Parenting on Children," University of Illinois Law Review 1997: 833-919).

Researchers studying gay and lesbian households also acknowledge difficulties in studying these families. Some they ascribe to a lack of reliable information on the number and location of gay and lesbian families, which prevents researchers from using random, representative samples in their studies. (Most research to date has involved small groups of white lesbian mothers who are comparatively better educated and wealthier than the general population. ) Another problem is that visible gay parenting is such a recent phenomenon that most studies are of the children of self-identified lesbians and gay men who became parents in the context of heterosexual relationships that dissolved before or after they assumed a gay identity. And a third problem is that since gay men and lesbians cannot marry, researchers cannot compare child outcomes between "married" and "unmarried" same-sex parents or similarly-situated heterosexual households.

Critics of the minority studies point to the lack of emprircal evidence included in these studies and to researchers' reliance, instead, on limited, theoretical explanations of the disadvantages of same-sex parenting. Some critics also maintain that the research is flawed by researchers' personal beliefs that homosexuality is either a sin, a mental illness, or a "learned pathology that parents pass on to children through processes of modeling, seduction, and contagion" (Stacy and Biblarz, "(How) Does the Sexual Orientation of Parents Matter?" American Sociological Review 66: 159-183 (Apr. 2001), quoting Cameron, Cameron, and Landiss, "Errors by the American Psychiatric Association, the American Psychological Association, and the National Educational Association in Representing Homosexuality...," Psychological Reports 79: 383-404 (1996)).


United States

In general, U. S. marriage rates declined and divorce rates increased in the last century. Experts have identified a number of factors that may have influenced the rates, including the women's rights movement, increasing societal acceptance of cohabitation and out-of-wedlock births, and the adoption of no-fault divorce laws. But there is no consensus on what has caused the overall trends. The table below shows marriage and divorce rates in the United States for the years 1940 through 2000 as calculated by the U. S. Centers for Disease Control.

We found no published study examining the effects of Vermont's civil union law, which went into effect July 1, 2000, on U. S. marriage or divorce rates at the state or national levels.

Vermont's Office of Vital Statistics reports that in 2000, the most recent year for which data is available, 6,271 couples married and 2,526 divorced. For 1999, the figures were 5,956 and 2,652, respectively.


Since 1989, Denmark has given same-sex, registered partners most of the rights and obligations it accords to married couples. The table below, based on statistics published by Denmark's central statistics office, shows the fluctuation in heterosexual marriage and divorce rates during the 12 years that the domestic partner registration law has been in place. Although we cannot offer an opinion on the cause, the marriage rate for heterosexual couples increased slightly during this period, while the divorce rate was generally unchanged.


OLR Backgrounders on Related Topics

Statements of Professional Associations

Critiques of Parenting Studies

Marriage and Divorce Rates

This backgrounder was prepared by Susan Price-Livingston, OLR Associate Attorney.