BACKGROUND: China now faces multiple challenging demographic and public policy problems that have emerged from four decades of sex-selective induced abortions. The sex-selective induced abortion of female fetuses has been under-examined quantitatively in China. METHODS: Using annual data on the officially registered number of births, induced abortions, and SRB data, we estimate the annual number of sex-selective abortions and then estimated two related proportions over the past decades. RESULTS: The annual proportions and number of selective abortions rose in the 1980s with the strict family planning policy and the diffusion of sex identification technology, remained at a high level between 1990 and 2010, and then declined, totaling 30.04 million. The abortion of second-order female fetuses was the largest proportion of all sex-selective abortions but declined after 2000 partly due to the change in birth composition by order. Children's composition affected sex-selective practice. Village selective abortions accounted for the majority of all selective abortions but decreased markedly in 2010 with changes in birth composition by residence. The rural-urban comparison by order indicated that urban couples were not less likely to abort female fetuses than their rural counterparts. Sex-selective abortions still exhibit provincial differences. CONCLUSIONS: In China, the long-standing preference for sons, easy access to sex-selective technologies, and the spontaneous fertility decline have led to the continued practice of selectively aborting female fetuses, despite its prohibition. As a result, the imbalanced sex ratio may take years to normalize.