guaifenesin, the chemical in
Robitussin and many other cough
syrups, not only thins the mucus in
your lungs but will also thin the mucus in your cervix, thus creating a slippery, healthy path for sperm to swim unhindered to the awaiting egg. In fact, doctors who prescribe Clomid to fertility patients often prescribe guaifenesin at the same time because Clomid can cause thicker "hostile mucus" in some patients. However, Dr.