"I LOVE my lesbian moms", read a hand-lettered sign which a teenager held up to motorists passing a county building in Portland, Oregon, where gay couples lined up to get marriage licences.

The message, prompted by the heated national debate over gay marriage, underscored a growing phenomenon - lesbian couples having babies and raising families.

According to the Family Pride Coalition, a national advocacy group for gay and lesbian families, some 9 million children in America have at least one gay parent and one in five lesbian coupled households include a child under 18.

"I wouldn't call it a baby boom exactly. It has been steadily growing all along," said Aimee Gelnaw, a lesbian mother of two and executive director of the coalition.

Using artificial insemination to get pregnant, lesbians are four times more likely to have children than gay men.

"Same-sex couples and single women are 40 per cent of our business, and it is the fastest-growing segment," said Marla Eby, vice president of marketing at California Cryobank Inc, Los Angeles, which ships semen nationwide.

The earliest lesbian-couple families often included children born into heterosexual marriages before the mothers "came out" as lesbians.

In the 1980s many sperm banks opened their doors to unmarried women, making unconventional families more feasible.

Gay pride celebrations have started to include child-centred events with face painting and play activities. Gay parents can flip through the glossy magazine "And Baby" geared to their families.

Choosing a donor

The first step for lesbian would-be parents is choosing a sperm donor. Gay rights groups say the matter goes beyond weighing physical and mental attributes. Legal issues can arise, such as whether the donor would let the child know his identity, when he or she comes of age.

Once the baby is born, couples often take legal steps to protect their families. In the states that allow it, the non-biological mother often adopts the baby so both the names of both mothers can go on the birth certificate.

Unlike heterosexual married couples, lesbians often have to draw up complicated wills and directives to protect their families should one partner die or the relationship end.

The fragility of these families was brought home in a story line of the television show "ER" in which a female doctor and a female fire-fighter have a baby together. When the fire-fighter dies, her parents - the biological grandparents - refuse to hand over the infant boy to his other mother.

"The story line is very significant in my own life," said "ER" executive producer Dee Johnson, who has two sons with her female partner of 10 years.

Gelnaw relocated while she was adopting her partner's baby. When a judge declared the adoption "provisional" Gelnaw had to fly back several times for follow-up interviews.

"I have a master's degree in child development and I had to prove I was a fit parent. I had to sit there with this caseworker and tell her what we feed Dewey (their daughter) for breakfast," Gelnaw said.

Despite greater acceptance generally, vocal opponents of same-sex parenting remain. "We do not support gay marriage, gay adoption or gay people becoming parents," said Michelle Ammons, director of communications for the Christian Coalition. "We don't support bringing children into the gay lifestyle."

Good parents

As a result, lesbian mothers sometimes move to "friendlier" states or communities, including Seattle and Portland.

Many lesbian couples also consider their children's well-being before they conceive, including the impact of not having a male role model in the home. Couples also worry that their children would be teased at school or the playground.

"We would have never had Carson if we had thought she would be bullied or have a hard time," said Liz Viggiano, a Portland nurse, rocking her 10-month-old daughter to sleep.

Studies show lesbian parents are doing a good job. "Absolutely, these kids do fine," said Dr Nanette Gartrell, a psychiatrist at the University of California, San Francisco, who is in the 18th year of a study on lesbian families created by donor insemination.

Sometimes the children themselves put the whole controversy into perspective. Gelnaw said her son Zack decided on his own to stop giving interviews by the age of 12.

"Time magazine wanted to talk with him. He usually enjoyed doing the interviews, but we discussed it and he said 'No, I don't want to do it. I'm just a kid with parents, there is nothing to talk about'."

(Agencies via Xinhua)