[1] The headword e)gku/monos is genitive singular -- evidently quoted from somewhere -- of the adjective e)gku/mwn "pregnant". In the phrase which glosses it e)gku/ou (genitive of the quoted nominative e)/gkuos, on which see next note) is from the same root and also means "pregnant" or "with child". Compare pi 1405 for a quotation from Josephus, Jewish War 3.245-7 (web address 1). It is perhaps the source of the form e)gku/monos in the present entry, though there are numerous other possibilities.
[2] If this two-word phrase is a verbatim quotation, its source is indeterminable. But it may not be: compare Hesychius epsilon272, where the lemma is the adjective alone, glossed with gunh\ e)ggastrwme/nh.