The included collection cups are specially treated with an enzyme (Chymotrypsin) to reduce the viscosity of the semen sample. Most samples will be thin enough to fill the dropper within 30 minutes after collection. If your sample is still too thick to fill the dropper, cap and swirl the cup again, and wait longer. Waiting up to 2 hours before starting the test is acceptable. If the sample remains too thick after 2 hours, discard the collection cup and sample, and test again in 2 to 7 days with a new collection cup. Drinking lots of water during the 24 hours before testing may help produce a more liquid sample.