Conservative activists marched through Paris on Sunday to protest a French bill that would give lesbian couples and single women access to in vitro fertilization and related procedures.
Traditional Catholic groups and far-right activists who held mass demonstrations against France's legalization of gay marriage in 2013 organized the protest, arguing that it deprives children of the right to a father.
LGBT activists and left-wing groups held a counter-demonstration against them.
Police blocked off several streets in Paris to prevent violence between the two groups.
Several other countries already offer assisted reproduction to lesbians and single women but French law currently allows it only for infertile heterosexual couples.
The bill is part of a broader bioethics draft law under debate at the National Assembly. France's health care system would cover the cost of the procedures for all women under 43.