Robitussin For Fertility???

So I was at our appt at the fertility specialist today, and I asked the Dr if Mucinex was actually good for helping mucus carry the swimmers over..and he said the he has heard of Mucinex being good but but that Robitussin was the best !! Has anyone ever heard if this ? Also I asked him about pressed because hubby and I have used it a few times...and he goes " you know what's even better ? Egg Whites !!!!" I almost fell out of my chair !! I'm not sure if these things will really help in aiding with fertility, but I'll try anything once ! Lol!