The reoccurrence in the film is a man's desire to have children, but ultimately must keep his wives (Micki & Maude) from meeting each other, particularly when they both have become pregnant.
Maude and Rob return home and briefly make out on the bed; the scene quickly ends there as they lie down. Sex is implied.
Another sex scene is subsequent (yet offscreen), clothes are strewed on the floor. Maude and Rob are seen in bed from the waist up; Rob's chest is the only nude visibility.
Maude and Rob are seen watching The 7th Voyage of Sinbad, where they reenact the monster fight in a playful, sensual manner. The scene ends, when Rob lies up top Maude and they kiss.
Micki has gloomy pajamas; she rolls over to kiss Rob and you can see her clothed buttocks for a moment.
Micki takes a shower, she can only be seen from the waist up. She then asks Rob to "wash the baby" and he complies as he washes her bare baby belly, smiling.
Rob does a male nude model shoot. All the models face from behind, exposing their buttocks. Nothing graphic, albeit Rob slams down the microphone against the interviewee's penis.