I am 38 years old married; I have Asthenozoospermia as per the following test result for my seminal fluid analysis according to reference WHO Norms’2010
Appearance: Normal
Liquefaction: Normal
Consistency: Normal
Volume: 3.0mL
pH:7.2
Concentration: 140M/ml
MOTILITY (%): 40%
A. Rapid Linear: 10%
B. Slow Linear: 20%
C. Non progressive: 10%
D. Immotile: 60%     
Viability (% live): N.A
MORPHOLOGY (Normal form %): 55%
WBC’s (x10/ml): Few
Agglutination: NO
What are causes the Asthenozoospermia?

Would you please advise according to the above test result what is solution for me to do in order to have children? Your earliest reply in same matter shall be highly appreciated.
Thanks “Kamrul”