Slovenia will decide on Sunday whether to allow homosexuals to adopt the children of their partners after a conservative group forced a national referendum on the issue.
The previous parliament, dominated by a centre-left coalition, passed a new family law in June 2011 but the Civil Initiative for Family and Children's Rights challenged it, arguing that homosexuals should not receive adoption rights.
By February the group, which enjoys the support of the Catholic Church, had collected the 42,000 signatures necessary for a national referendum.
Opinion polls show voters are likely to narrowly endorse the law.
Under the legislation, gay couples do not have the right to adopt children from a third party but conservative groups want it annulled because it allows homosexuals to adopt the children of their partners.
"We are against the new family law because it does not recognize the exceptional importance of women and men in giving birth, the personal development and upbringing of children, and does not bring new rights to children," Ales Primc, head of the civil group which initiated the referendum, told Reuters.
"It also paves a way for a homosexual education in the school system and we believe such an education should be followed only in agreement with parents."
The small Adriatic country which joined the European Union in 2004 is relatively tolerant of homosexual couples, who have been able to formally register their relationship since 2006.
Last year a court sentenced three Slovenians to up to seven months in jail for attacking a gay activist in Ljubljana in 2009.
Human rights ombudsman Zdenka Cebasek Travnik told Reuters the public was unnecessarily focused on the issue of gay adoption rights because the law also contained "many, many things that are distinctively in favor of all children".
The law envisages a special ombudsman for children's rights and is expected to speed up court processes on matters concerning children's rights. It also simplifies divorce for childless couples.
Slovenians have rejected five laws in a row in referendums over the past 16 months, which paved the way for parliament to oust Prime Minister Borut Pahor's government in September.
The new conservative cabinet of Prime Minister Janez Jansa, which took office last month after a December election, is not participating in the referendum campaign although three of the five coalition parties oppose the family law.