twin fetuses lock together
... that when twin fetuses lock together during childbirth, the first twin is sometimes decapitated to save the second?
... that when <b id="mwCFg"><a href="./Locked_twins" id="mwCFk" rel="mw:WikiLink" title="Locked twins">twin fetuses lock together</a></b> during childbirth, the first twin is sometimes <a href="./Decapitation" id="mwCFo" rel="mw:WikiLink" title="Decapitation">decapitated</a> to save the second?