Yes, it is generally safe to have sex during pregnancy unless advised otherwise by your healthcare provider. However, after reaching 21 weeks of gestation, certain positions may be more comfortable and safer for both you and your baby. The best positions for sex during pregnancy include side-lying, spooning, or woman-on-top with support. These positions help minimize pressure on your abdomen and provide better comfort. It's important to communicate with your partner about any discomfort or concerns you may have and always consult with your healthcare provider for personalized advice based on your specific situation.