There are more words but they are from Tolkien's earlier conceptional periods. Tolkien likely changed these words as he evolved the aesthetics and completeness of the languages. You may even find languages that Tolkien later rejected. Do not mix words from different time periods unless you are familiar with the phonetic developments.
pukta-
verb. *to copulate
pukta
noun. coitus, *sex
puhta
noun. coitus, *sex
A noun appearing as ᴱQ. puhta or pukta (the second possibly a primitive form) in Early Noldorin Word-lists of the 1920s as the cognate of ᴱN. hoith “coitus” (PE13/147, 163), probably derived from a variant form of the early root ᴱ√PU(HU) “generate” (QL/75).
Neo-Quenya: I would retain this word as ᴺQ. puhta “coitus, ✱sex” for purposes of Neo-Quenya based on a Neo-Root ᴺ√PUK for Elvish “sex” words.
Below: Tolkien's Late Period (1950–1973). These are from Tolkien's late conceptual period — his most settled forms of the languages. Prefer these over the earlier ones above when composing new text.
A verb appearing as ᴱQ. pukta- in the Qenya Lexicon of the 1910s under the early root ᴱ√PU(HU) “generate” (QL/75). According to the editors, it was written over an erased word whose glosses seems to have been “coire”, which is Latin for “to copulate”; elsewhere derivatives of this root had to do sex and sexual organs.
Neo-Quenya: For purposes of Neo-Quenya I would adapt this word as ᴺQ. puhta- “to copulate, have sex” as suggested by Fiona Jallings, with the later Quenya sound change of kt to ht.