The theory of "yang transforms into qi while yin constitutes form" is the general outline of the yin-yang theory in traditional Chinese medicine

which embodies the concept of life contained in the ancient philosophical thought of China’s ancient medical practice. The spermatozoa can move and fertilize under the warming and propulsive effect of "yang transforms into qi"

while they are produced and their morphological and structural integrity is maintained under the cohesive effect of "yin constitutes form" . The malfunctioning of "yang transforms into qi while yin constitutes form" is an important pathogenesis of male infertility. Abnormality in the process of "yang transforms into qi" leads to insufficient activity and motility rate of the sperm

and dysfunction of "yin constitutes form" may induce low sperm count and high sperm deformity rate

and even high sperm DNA fragmentation rate. This theory can thus provide some insights into male infertility. TCM syndrome differentiation and treatment of the disease should be based on its pathogenesis

focusing on warming and activating kidney yang and aiding the transforming of yang into qi

enriching and nourishing kidney yin and condensing yin

and harmonizing yin and yang

tonifying the kidney and supplementing the essence. The clinical medication should follow the characteristics of using more herbal medicine of the seed category and adding animal-based ingredients when needed

and the creation of the prescription should be guided by the theory of "a stem formula for the dominant pathomechanism" . Jujing Decoction (Essence-Gathering Decoction) nourishes kidney yin while warming kidney yang to seek yin within yang

and also invigorates blood and dissolves stasis

with the recipe containing primarily seed medicine

and also blood and flesh products when appropriate. It has been shown in a previous study that Jujing Decoction can effectively improve sperm vitality

reduce sperm malformation rate and improve sperm DNA fragmentation index

and has a desirable safety profile.