Many pregnant women wonder if vigorous or 'hard' sex is safe during pregnancy. Generally, sex is safe unless your doctor advises against it due to complications like placenta previa or preterm labor risks. While deep penetration or certain positions might become uncomfortable as your pregnancy progresses, there's no evidence to suggest that hard sex will directly harm the baby, who is well-protected by the amniotic sac and uterus. However, always listen to your body and communicate openly with your partner and healthcare provider about any concerns.