Robitussin???!

I have read somewhere that ladies who are TTC have drank Robitussin a few times a days for a few days right before ovulation and the result in the end was a BFP. (The mechanism is that the guafenesin in the medicine is an expectorant and the same way it thins and loosens the mucus in your nose or throat, it does the same down there and thereby making it easier for fertilization and implantation )