Lupigest SR 300 Tablet contains 300 mg of natural micronized progesterone, a bioidentical hormone essential for regulating the menstrual cycle and maintaining pregnancy. This sustained-release formulation ensures gradual absorption, providing stable plasma levels over an extended period. Progesterone plays a critical role in preparing the endometrium for implantation of the fertilized ovum and supports early pregnancy by maintaining the uterine lining. Lupigest SR 300 is commonly prescribed for conditions associated with progesterone deficiency such as luteal phase defects, amenorrhea, abnormal uterine bleeding, and as part of hormone replacement therapy in menopausal women. It is also utilized in assisted reproductive techniques to enhance endometrial receptivity and reduce the risk of miscarriage. The natural micronized form improves bioavailability and reduces gastrointestinal side effects compared to synthetic progestins. Administration should follow medical guidance, with dosage tailored to individual clinical needs. Contraindications include known hypersensitivity to progesterone, unexplained vaginal bleeding, active thromboembolic disorders, and certain hormone-dependent cancers. Caution is advised in patients with liver dysfunction or a history of depression. Common adverse effects may include dizziness, headache, breast tenderness, and mild gastrointestinal discomfort. Regular monitoring and follow-up are recommended to optimize therapeutic outcomes and minimize risks.