Progesterone, which regulates cyclical changes in the endometrium of the uterus and maintains a pregnancy An acute exacerbation is more commonly known birli a 'flare-up'. An acute exacerbation of chronic obstructive pulmonary disease (COPD) is a sudden worsening of COPD symptoms compared with the usual severity of symptoms. Less common https://search.grainger.illinois.edu/searchaidlog3/sourcelognew.asp?ID=782151&goog--https://tr.wikipedia.org/wiki/Vitamin