Which of the following is a synthetic progesterone ?

Norethindrone

The correct answer is option 3. Norethindrone.

Here is an explanation of why option 3 is the correct answer:

Norethindrone, also known as norethisterone, is a synthetic progestin, which is a synthetic form of the hormone progesterone. Progestins like norethindrone mimic the effects of natural progesterone in the body. Progesterone plays a crucial role in the menstrual cycle and pregnancy by regulating the menstrual cycle, preparing the uterus for pregnancy, and maintaining pregnancy.

Usage:

Contraception: Norethindrone is commonly used in hormonal contraceptives, including birth control pills (oral contraceptives). It works by suppressing ovulation, thickening cervical mucus to prevent sperm from reaching the egg, and thinning the uterine lining to prevent implantation.

Hormone Replacement Therapy (HRT): Norethindrone is also used in hormone replacement therapy to treat symptoms of menopause, such as hot flashes and vaginal dryness. When combined with estrogen, it helps balance hormone levels in women experiencing menopausal symptoms.

Forms: Norethindrone is available in various forms, including oral tablets, patches, and intrauterine devices (IUDs), depending on the specific product and indication.

Side Effects: Common side effects of norethindrone may include nausea, breast tenderness, irregular bleeding, and mood changes. Serious side effects are rare but may include blood clots, especially in women who smoke or have other risk factors.

Comparison with Other Options:

Novestrol: Novestrol is a synthetic estrogen compound, not a synthetic progesterone. Estrogens play a different role in the menstrual cycle and pregnancy compared to progesterone.

Mifepristone: Mifepristone is a synthetic steroid compound with anti-progestational properties. While it interacts with progesterone receptors, it is not a synthetic progesterone itself. It is used for medical abortion and other reproductive health purposes.

None of the above: This option is not applicable because norethindrone is indeed a synthetic progesterone and fits the description provided.

Summary:

Norethindrone is a synthetic progestin commonly used in hormonal contraceptives and hormone replacement therapy. It mimics the effects of natural progesterone in the body and is effective in preventing pregnancy and treating menopausal symptoms. Its versatile applications make it an important component of women's health care.