There may be rules in modern Japanese regulating this, perhaps observed by TV announcers. However, practically, I believe it is more natural to produce the sound きゅ
than a forced き-う
. The same goes for 霧生
. In fact, 霧生
is spelled with きりゅう
in many cases. Some people might prefer to split イ+ウ
if they are separate morphemes... but practically, they are just so ambiguous when pronouncing.
From a history point of view, there was no clear difference between きゅ
or きう
. Actually, the small notation of 拗音 (contracted word) is adopted after the WWII (現代かなづかい in 1946). Before that, in old literature like 徒然草 (Tsurezuregusa) in the 14th century, there was あやしうこそ in the preface passage, which in modern day notation (and pronunciation) would be あやしゅうこそ.
For 言う
being pronounced as ゆう
, the pronunciation existed long before this notation of 言う
, so the rule of how to produce イ+ウ
should not be deduced from the notation. 言う
was written as 言ふ
in old notation.