Actually it should say “Don’t let liberals encourage you to get pregnant at 14”
Biology and Pop Culture "encourage you to get pregnant at 14". Loving parents do all they can to prevent that. Civilized society supports parents in that mission.
Ergo, many parents and much of society is neither loving nor civilized.
That portion which does discourage premarital copulation is usually labeled "repressive", "out of touch", "unrealistic", "Victorian/Puritan", etc, etc.
Simple solution: