There are many advantages to rear entry. Back Pain During Pregnancy: There's more to intimacy than sex. This position can lead to a lot of role playing, which can add nude pinup girls element of humour and spice up the whole act! Therefore during the first trimester of your pregnancy sex will be fun and pleasurable and you can enjoy sex without any inhibitions. When you do venture back, it's important to make your partner aware that Harmful sex positions during pregnancy may need plenty of foreplay and possibly lubrication.