Nicaragua has taken a step backwards by defining marriage as only being possible between a man and a woman.
On Wednesday, the Central American country’s new Family Code, including this exclusionary definition, came into effect.
The law, which was approved by the Nicaraguan Congress last year, also bars the adoption of children and the use of fertility treatments by gay couples or individuals, only allowing heterosexual couples to do so.
The new provisions ensure that same-sex couples and their families have none of the rights or benefits accorded to heterosexuals.
LGBT rights groups are planning to take the discriminatory elements of the family code to the Supreme Court.
Male and female homosexuality were only legalised in 2008 in the predominantly Catholic country.
A 2013 survey conducted by the Pew Research Center found that just 16% of Nicaraguans support same-sex marriage while 77% are opposed to it.