Since Spain's transition to democracy, abortion has been a public policy issue both inside and outside parliament. This paper describes the history of abortion law reform in Spain from 1979 to 2004 and analyses the discourse on abortion of members of the Spanish parliament by sex and political allegiance. The analysis is based on a retrospective study of the frequency of legislative initiatives and the prevalence of different arguments and positions in debates on abortion found through a systematic search of the parliamentary database. Little time was given to abortion in the parliamentary agenda compared to other women's issues such as violence against women. There were 229 bills and other parliamentary initiatives in that period, 60% initiated and led by pro-choice women. 143 female and 72 male parliamentarians took part in the debates. The inclusion of socio-economic grounds for legal abortion (64%), and making abortion on request legal in the first 12 weeks of pregnancy (60%) were the most frequent forms of law reform proposed, based most often on pro-women's rights arguments. Male and female members of anti-choice parties and most male members of other parties argued for fetal rights. Pro-choice parties tabled more bills than anti-choice parties but till now all reforms proposed since 1985 have been voted down.