The Compendium of Caraka 4.2.19

4.2.19

śukrāśayadvāravighṭṭanena saṃskāravāhaṃ kurute 'anilaśca/
mandālpabījāvabalāvaharṣau klībau ca heturvikṛtidvayasya//

And wind, by obstructing the entrance of the seminal receptacle, produces the semen-transporting condition; / seeds that are sluggish and small, weak, and devoid of arousal are the cause of the two types of impotent persons.