First - if you got a chemical last month - then that is really promising.
Did you use a trigger shot last month? Which one?
Some people with LUFS cannot release with Ovidrel and must use something stronger - like Lupron. Others don't release every month. You could be in that category. You may want to use a trigger shot every month "just in case."
Have you been doing all of your IUIs with Coopers?