Thanks for your query.Based on the facts that you have posted it is not clear what is the percentage of active motile sperms reported in your semen analysis
Active motile sperms are those who move at a fast speed in a straight line and capable of fertilising female egg.resulting in pregnancy
while sluggish motility indicates sperms moving in a curvilinear and zigzag pattern with slow speed These sperms can not fertilise ovum.(Female Egg).
Normal values of active motile sperms should be in a range of 30 to 50% active sperms
Since you have grade three varicocele
on left side you can undergo surgery of Varicocele.This will help in increasing sperm count
and quality of sperms.