Yes, it is safe to do so. Just take note not to adopt a lying down position when engaging in sex (for example, missionary), as the weight of your baby will be on your organs. It will be quite tough on you when your LO is weighing down on your insides.
If ur pregnancy is smooth so far with bo complications, it shld be ok but do get ur gynae's advice. Be careful frm 35th wk onwards tho as it may cause contractions.