Fertility 101: Male Fertility
Sperm Analysis with Kruger Morphology
"Morphology" simply refers to the shape of the sperm. Carolina Conceptions uses the method of “Krueger Strict Morphology” when we evaluate the appearance of sperm under a microscope. The shape of the sperm is a reflection of proper sperm development in the testicles. If a man has a decreased number of normally shaped sperm, he is at risk of fertilization failure or at least low rates of fertilization.
Strict morphology is a useful test to perform with couples that have unexplained infertility, even if the semen analysis is otherwise normal. In a semen specimen, all men will have some sperm with a normal appearance and some with an abnormal appearance. Over the years, different criteria have been used to distinguish normal from abnormal sperm and different "cutoff" levels have been used for what is considered "normal". The concept behind strict morphology, as the name suggests, is to evaluate sperm much more closely than in the past and use a stricter determination for what is considered normal. A normal percentage under Kreuger's criteria is 14% normal. A normal morphology assessment using the Krueger method correlates much more closely with male fertility.
Normal: > 14%
Good (Borderline): 5-13%
Poor: 0-4%