What do the four experts think of obstetrics and gynecology?

The four masters in Jin and Yuan Dynasties also had many original opinions on obstetrics and gynecology. For example, Zhang Congzheng believes that when treating gynecological diseases, stop bleeding with caution; People who see postpartum diseases must ask if there is lochia. Dai Li put forward the principle of "regulating qi first, then treating blood diseases" in gynecology. Zhu Zhenheng has the theory and prescription of "clearing heat and nourishing blood before delivery and tonifying qi and blood after delivery". In the Ming and Qing Dynasties, there were more famous doctors' masterpieces, such as The Standard of Gynecology Based on Syndrome Differentiation and Treatment, Wu's Outline of Benefiting Yin, and Fu Shan's Gynecology, all of which were masterpieces of gynecological experience in past dynasties, and were precious treasures of Chinese medicine, and spread to Korea, Japan and other countries.