Thesis: An AOC law with very different penalties for safe and unsafe coitus may protect the children better from pregnancy than the current laws.
Really, if the decision for the pedophile is "no sex or danger of prison", many pedophiles will use "danger of prison", because a whole life without sex seems to be too harmful.
But, if the decision is "safe sex or danger of prison", the pedophile must be a fool if he makes unsafe sex.
To get an optimal result (if the aim is to avoid pregnancy) the relation between the penalties for safe coitus, unsafe coitus and other techniques without danger of pregnancy (masturabation, fondling) has to be connected with the danger of pregnancy for safe and unsafe coitus. Thus, the penalty for safe coitus must be sufficiently lower as it is now, and a penalty for other sexual techniques cannot be justified by this reason.