If they refuse, or make excuses about why they can't provide the details in writing, you should seriously consider going to another clinic - they probably have low pregnancy rates. Some IVF centers have very low pregnancy rates. All couples considering IVF treatment should get a written statement of their clinic's recent pregnancy rates and evaluate them in relation to other available clinics. The average charge at other centers is higher than this. It is important not to equate price with quality when it comes to IVF .
Some centers are very expensive and have very low success rates.