Depends on how funny what Morinas said is. Since secondary characteristics disappearing is gradual, development of genetalia would take time too. It'd probably physically be the same yuri schoolgirl sex there, five minutes after.
Though the situation got me thinking too much as usual. What happens when you get sperm in the spring water? Does it randomly scramble chromosome 23? Could you get material for males from birth by desecrating a holy site? Probably requires an interpretation or choice regarding gender by the mind in order to work to prevent that.