Hormonal Contraception 2005

by Joyce Cheung, M.D.

(presented at the CAMS 2005 Annual Scientific Meeting)

Women spend 75% of their reproductive years trying to avoid unintended pregnancies. Yet, approximately 3 million unintended pregnancies occur each year in the U.S.  The importance of contraception is clearly important to everyone as an individual which in turn impacts society as a whole.

The interest in hormonal contraception started in the 1920's but it was not until the 1950's- 1960's that effective progestins were patented.  The key to hormonal contraception today is to give the lowest doses that will provide effective contraception.

The progestin component of hormone contraception inhibits ovulation, produces a non-receptive endometrial environment for implantation, thickens cervical mucous, and influences tubal peristalsis.  The estrogen component prevents the selection of a dominant follicle, stabilizes the endometrium, and increases the concentration of intracellular progestational receptors.

Aside from contraceptive benefits, hormonal contraception (OC) provides many other non-contraceptive benefits.  Ovarian cancer is reduced by 40% by just one year of OC use.  Endometrial cancer is reduced by 50%.  Dysmenorrhea is improved, and mild to moderated acne can be treated.  Lighter menstrual flows from taking OC results in less anemia.  Mittelschmertz, pelvic inflammatory disease, benign breast disease are all reduced. 

Unfortunately, even the best medications have side effects, and contraindications.  Some side effects with hormonal contraception include break-through-bleeding, weight change, headaches, mood changes, nausea, breast tenderness, thrombotic effects, and lipid profile alterations.  Contraindications to OC usage include thromboembolic disorders, history of DVT, CVA, CAD, endometrial cancer, undiagnosed genital bleeding, smokers >35 years old, pregnancy, and others.

 In 2005, there are lots of OC's to choose from.  All OC use ethinyl estradiol as the estrogenic component, and they are either mono-phasic or multi-phasic.  The common progestational agents today include Norethindrone, Norgestimate, Levonorgestre, and Desogestrel.  Newer options today include Seasonale (extended regimen OC), Ortho Evra (transdermal contraceptive), Nuva Ring (transvaginal ring contraceptive), Mirena (Levonorgestrel intrauterine system), and Depo Provera (Medroxyprogesterone injection). 

 Choosing the right formulation for the patient with medical problems may be challenging.  But the American College of Obstetrics and Gynecology (ACOG) has put out recommendations based on evidence based medicine making our decisions easier.  Questions addressed include what to do for women >35 years, smokers, those with hypertension , diabetes, headaches, breast disease, and thromboembolic problems. 

Dr. Cheung is Clinical Instructor of Obstetrics & Gynecology, NYU Medical School and Attending Physician, Beth Israel Medical Center.