i would think that would include orgasm. i think orgasm is the primary concern, as orgasm causes the uterus to contract. oral sex w/out orgasm would be okay though.
You know what I was told the same at 14weeks I believe or 15weeks.. of having a low lying placenta and recommend not to carry anything heavy nor have sex but I didn't listen lol I still had sex but we took it easy not so rough and im fine know but its really up to you. Oral sex is okay of course if you meant anal then Idk . But at.21weeks my placenta moved up and I'm doing fine :)