Which one of the following is not a third generation progestrogen used in combined oral contraceptive pills ?

Ans. is 'a' i.e., Levonorgestrel Generations of progesterone 1. First generation Has low progestational selectivity, so also possess some estrogenic activity. ta Has androgenic action (but less than 2nd generation) Examples Norethindrone, ethynodiol diacetate 2. Second generation Has more progestational selectivity than first generation Androgenic action is also more than 1st generation Examples Levonorgestrol (the most widely used progestin), Norgestrel. 3. Third generation Has highest progestational selectivity Has very low androgenic activity (some even are antiandrogens, e.g. drospirenone) Examples : Desogestrol, Norgestimate, Drospiren one, Gestodene