Pope Francis is critical of the notion of safe sex. I suspect this is less a matter of dangerous sexual contact and more one of a regard for the possibility of people having a mature wait for a marital commitment:
283. Frequently, sex education deals primarily with “protection” through the practice of “safe sex”. Such expressions convey a negative attitude towards the natural procreative finality of sexuality, as if an eventual child were an enemy to be protected against. This way of thinking promotes narcissism and aggressivity in place of
acceptance. It is always irresponsible to invite adolescents to toy with their bodies and their desires, as if they possessed the maturity, values, mutual commitment and goals proper to marriage. They end up being blithely encouraged to use other persons as an means of fulfilling their needs or limitations. The important thing is to teach them sensitivity to different expressions of love, mutual concern and care, loving respect and deeply meaningful communication. All of these prepare them for an integral and generous gift of self that will be expressed, following a public commitment, in the gift of their bodies. Sexual union in marriage will thus appear as a sign of an all-inclusive commitment, enriched by everything that has preceded it.
Remember that Amoris Laetitia is online here.