Drawing on a large dataset at the district level for mid-19th century Spain, this article shows not only that average (male-to-female) infant and childhood sex ratios were relatively high, but also that some regions experienced extremely high figures, thus pointing to some sort of excess female mortality. The analysis also suggests that economic deprivation was likely to trigger gender discrimination towards newborn and/or young girls. Although less conclusive, there is also evidence that certain social and cultural contexts could have also mitigated this behaviour.