What Causes Fluctuations In Sperm Count?

hello doctor , i would like to know the reason of flactuation in sperm count over two years , the first was 28 million , second 8 million , third 8 million , latest one was 20 million and more than 40 in total ejaculation , and in all tests the viscosity ( agglutination ) was high . and does spemen pills from himalaya product is usefull , am using antioxidant + zinc + Vit E + Sellenium + Vit C + BIOSOLVON .