The daughter of Cuban President Raul Castro spoke here before some 100 people at a conference entitled "A Look at Sexual Diversity from the Political Point of View," but declined to answer questions from reporters.
"I'm not going to give interviews, I came here to work," was all Mariela Castro would say when questioned by reporters.
Members of her team told Efe that Castro also would not speak with the media on previous days and that all her comments, including political ones, were in answer to questions asked by those registered to attend her talks.
Castro's address to an audience of some 100 people was part of an event organized by the Latin American Studies Association at a downtown San Francisco hotel.
Fidel Castro's niece recounted the struggle for gay rights in Cuba since the 1960s - when gays and lesbians were persecuted - up to the more favorable situation at present.
"The Cuban Women's Federation, together with the association of Cuban jurists and other institutions, is currently promoting a bill that would modify the Family Code passed in 1975 to include a new article requiring respect for freedom of sexual orientation and gender identity, and which also sanctions legal unions of same-sex couples," Castro said.
Castro has been in the Northern California city since Tuesday, where she has participated in meetings, a doctors' forum and a discussion organized by the community of lesbians, gays, bisexuals and transsexuals.
On the other hand, the 50-year-old director of Cuba's National Center for Sex Education blasted Wednesday the "mafia of Cuban emigres" for blocking Americans from freely visiting the Caribbean island.
She also said she "would vote for (Barack) Obama for president," especially after the U.S. president said he favored gay marriage.
"I think it's something he truly believes in. If I were a U.S. citizen I'd vote for Obama for president," she said. "I think he is sincere, I think he speaks from the heart."
Mariela Castro received a visa from United States authorities to be able to attend the 30th LASA Congress, which ended Saturday.
That decision stirred a big controversy among certain groups, especially from the campaign of presumptive Republican presidential nominee Mitt Romney.
"The Obama administration's decision to grant a visa to Mariela Castro, daughter of Cuban dictator Raul Castro, is a slap in the face to all those brave individuals in Cuba who are enduring relentless persecution for fighting for the universal rights we Americans hold dear," Romney's policy director, Lanhee Chen, said last week in a statement.
Next Tuesday Mariela Castro will attend another conference on gay rights in New York. EFE