LHB also known as CGB4, LSH-beta, LSHB is a member of the glycoprotein hormone beta chain family and encodes the beta subunit of luteinizing hormone (LH). LHB plays a vital role in reproductive health by regulating spermatogenesis in males and ovulation in females through stimulation of steroid hormone production in testes and ovaries. The structure of LHB is particularly important, as LHB is a heterodimer composed of a common alpha chain and a unique beta chain, which is essential for biological activity and receptor binding. The presence of different isoforms of LH, resulting from proteolytic processing and metabolism, highlights the complexity of regulation and function in the endocrine system. LHB exists in various isoforms through proteolytic processing, influencing stability and function in circulation.