Denmark was the first country to introduce civil partnerships for same sex couples in 1989, since when several European Union countries, some US states, Australia and Canada have followed suit.
The authors point to evidence, which suggests that gay men and lesbians do not receive the same standard of health care as straight people.
Rates of depression, anxiety, substance misuse, and suicidal behaviour are also all higher among gay men and women than straight people. Discrimination, prejudice and intolerance on religious grounds are likely to be partly to blame for this, say the authors.
They suggest that civil partnerships are likely to break down some of this prejudice and promote greater understanding, including among staff working in the health service.
They argue that legal civil partnerships could increase the stability of same sex relationships and minimise the social exclusion to which gay and lesbian people are often subjected.
Previous research shows that "married" same sex couples had greater openness about their sexual orientation and closer relationships with their relatives than same sex couples not in civil partnerships.
Despite the high divorce rates, there is a considerable wealth of evidence to suggest that married couples have better mental and physical health and tend to live longer than single people.
There is no reason why these same benefits should not be conferred on same sex marriages, say the authors.
But universal acceptance of same sex civil partnerships, with the equivalent status, recognition, and legal benefits as conventional marriage, still has some way to go, say the authors.
They report that 4,000 gay marriages in San Francisco were recently annulled by the California Supreme Court because they were considered a violation of 1977 state law, defining marriage as a union between a man and a woman. The Vatican also equates same sex unions with "deviant behaviour."