(NEW YORK) -- Current state laws put many children living in lesbian, gay, bisexual and transgender (LGBT) families at risk and undermine family stability, according to a new report out Tuesday.
In more than 30 states, children in LGBT families are legal strangers to at least one of their parents.
In Louisiana, for example, one would have to be the biological parent or legally married to his or her partner to secure parenting rights. Same-sex marriage is illegal in that state and two men's or women's names cannot appear on the birth certificate.
Between 2 million and 2.8 million children are being raised by LGBT parents, and because of a patchwork of state laws and no federal protections, many of these children are at risk, according to the report by the Movement Advancement Project, Family Equality Council, Evan B. Donaldson Adoption Institute and the Equality Foundation.
The findings are based on a 2011 report, "Children Matter: How Legal and Social Inequities Hurt LGBT Families." This third companion report recommends policies and laws that the groups say address the changing American family and protect children.
In the United States, 69 percent of children live with married, heterosexual parents, down from 83 percent in 1970, according to the report. Today, an estimated 24 percent of female same-sex couples, 11 percent of male couples and 38 percent of transgender Americans are raising children.
The states with the highest number of children being raised by LGBT families -- many of them in the conservative South -- are those with the most restrictive laws.
While states like California and New York have high numbers of same-sex couples, those most likely to be raising children live in Mississippi, Wyoming, Alaska, Arkansas, Texas, Louisiana, Oklahoma, Kansas, Alabama, Montana, South Dakota and South Carolina, in that order.
A second legal parent may be unable to pick up a child from day care without authorization or advocate for a child in school. In these states, nonbiological same-sex parents cannot include a child on their health insurance and can be denied access to a hospital in an emergency or be left out of health care decisions.
Inconsistent laws make it difficult even for families from states where same-sex marriage and second-parent adoption is legal when they cross state lines, according to the report.
"If a couple in Washington, a state with full parental recognition, goes on vacation jet skiing in Idaho and the kid gets hurt, one parent might not be recognized," said Calla Rongerude, spokesman for the Movement Advancement Project, an LGBT think tank, and one of the co-authors of the report.
"If you are a New York family visiting Philadelphia, you better take everything you have and hope there is a sympathetic nurse when you have to go to the hospital," she said.
Children are also unable to access death or disability benefits or government safety net programs from a non-legal parent. They can lose inheritance and other protections designed to keep them safe during times of crisis, according to the report.
"When we talk about ballot measures on marriage, we don't talk about the kids," said Rongerude. "And frankly, they are the most vulnerable."
Copyright 2012 ABC News Radio