II. General
- Ability to prevent spotting or breakthrough bleeding
- Dependent on Estrogen-Progestin ratio
- Bleeding may be due to:
- Estrogen insufficiency
- Progesterone insufficiency
III. Progestins with least potent Endometrial Activity
- Amount to suppress bleeding for 20 days in 50% women
- Gestodene (12.6)
- Desogestrel (8.7)
- Levonorgestrel (5.1)
- dl-Norgestrel (2.6)
IV. Progestins with most Endometrial Activity
- Amount to suppress bleeding for 20 days in 50% women
- Norethynodrel (0): Low limit reference
- Norethindrone Acetate (0.4)
- Ethynodiol Diacetate (0.4)
- Norethindrone (1.0)
V. Oral Contraceptives with least Endometrial Activity
- Least suppression of bleeding
- Progestin-Only (Mini-Pill)
- Demulen 1/35
- Loestrin
- Tri-Norinyl
VI. Oral Contraceptives with most Endometrial Activity
VII. References
- Cerel-Suhl (1999) Am Fam Physician 60(7):2073 [PubMed]
- Speroff (1993) Obstet Gynecol 81:1034-47 [PubMed]
- Dickey (1998) Managing Contraceptive Pill Patients