SANTIAGO, Chile –  Dozens of same-sex couples in Chile are celebrating civil unions, taking advantage of a new law that’s a sign of change in a country long regarded as one of Latin America’s most socially conservative.

The civil union law that passed in April went into effect Thursday and couples have been arriving at civil registry offices early to officially validate their unions.

Some are wearing matching traditional Chilean cowboy garb, others elegant tuxedos and dresses.

Civil unions have been recognized in several South American countries, though only Argentina and Uruguay allow formal gay marriage.

Gay advocates in Chile are celebrating the right to same-sex civil unions as a step toward full rights.