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Oral Contraceptive Pill: A General Overview. Kristy Van Kirk. Case: Healthy 23 year old female . Taking Ortho Tri-Cyclen reliably for years, G 0 Married 1 year Switched to generic to save money Asked pharmacist if secondary form of contraception would be necessary for first month of switch
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Oral Contraceptive Pill: A General Overview Kristy Van Kirk
Case: Healthy 23 year old female • Taking Ortho Tri-Cyclen reliably for years, G0 • Married 1 year • Switched to generic to save money • Asked pharmacist if secondary form of contraception would be necessary for first month of switch • “No, generic is essentially the same” • Never missed a pill, but occasionally took a pill a little later in the day • Unplanned pregnancy: expecting March 2004
Epidemiology • 98% of women who had sexual intercourse used at least one method of contraception.1 • Oral contraceptive pill is the most popular form of contraception: 11.6 million US women in 2002.1 Nineteen percent of women ages 15-44 (CDC’s National Center for Health Statistics). • Followed by female sterilization, condoms, male sterilization, and other methods.1 • 49% of pregnancies were unintended in 2001.2 • 1. Kaiser Family Foundation. Women’s health care providers’ experiences with emergency contraception. Kaiser Family Foundation. June 2003. • 2. Disparities in Rates of Unintended Pregnancy in the United States. 1994 and 2001. Finer LB, Henshaw SK, Perspectives on Sexual Reproductive Health, 2006:38:90–96. Health, 2006:38:90–96.
Pulsatile GnRH (hypothalamus) LH and FSH (anterior pituitary) LH stimulates: Ovulation (36 hrs after LH surge) FSH stimulates: Folliculogenesis Estradiol production Estradiol and progesterone (ovaries) Estradiol: Initial negative feedback on hypothalamus and pituitary Endometrial proliferation When high enough long enough, switches to positive feedback resulting in LH secretion Progesterone: Elevation indicative of ovulation “Pro-pregnancy” Inhibits LH & FSH Review: the menstrual cycle
How does hormonal contraception work? • Estrogen: • Prevention of estrogen surge, which prevents LH surge → no ovulation • Suppression of gonadotropin secretion during follicular phase, preventing follicular maturation and preventing ovarian hormone production • Progesterone: • Creates thick cervical mucus to hinder sperm penetration • Impairs normal tubal motility and peristalsis • Martin KA, Barbieri R, Up To Date: Overview of the use of estrogen-progestin contraceptives. Available online. (Accessed Jan 30 2007).
Hormonal Contraception Options • Combined oral contraceptives (COC) • (Mestranol)→ethinyl estradiol • Estrogen level has decreased from 100 mcg/day → as low as 20 mcg/day • Most women should get no more than 35 mcg/day ethinyl estradiol • 50 mcg estrogen may be appropriate if: • Spotting, absence of bleeding, or dysfunctional uterine bleeding; Acne; Ovarian cysts; Endometriosis; Drug interactions (induction of Cytochrome P450) • Progestins • Most potent: desogestrel, levonorgestrel, norgestrel • Least potent: norethindrone • Most androgenic: norgestrel > norethindrone & ethynodiol • Least androgenic: desogestrel & norgestimate → may ↓ risk of MI • Hormonal contraception. Pharmacist’s Letter/Prescriber’s Letter 2006; 22 (8):220809.
Hormonal Contraception Options cont’d. • Monophasic vs. biphasic vs. triphasic • Biphasic and triphasic thought to more closely mimic fluctuations in estrogen and progesterone levels during the menstrual cycle; ↓ dose-dependent adverse effects of progestin • Recent Cochrane reviews conclude that choice of progestin is more important than phasic formulation • Progestin-only pills (POP) • Women who are breastfeeding-can be started immediately postpartum • Considered safer in women w/ migraines, hx of thromboembolic disease, poorly controlled HTN w/ vascular disease or >35 yrs, diabetes w/ vascular disease or >35 yrs, SLE w/ vascular disease, hypertriglyceridemia, smoker over 35 yrs of age, CAD, CHF, cerebrovascular disease • Hormonal contraception. Pharmacist’s Letter/Prescriber’s Letter 2006; 22 (8):220809.
Comparison of Oral Contraceptives • Low-dose Monophasic Pills • Alesse, Levlite: low estrogen/progestin/androgen • Loestrin 1/20, Fe 1/20: low estrogen, high progestin, medium androgen • Nordette, Low Ogestrel: low estrogen, medium progestin, medium/high androgen • Loestrin Fe 1.5/30: low estrogen, high progestin, high androgen • Ortho-Cept: low estrogen, high progestin, low androgen • Yasmin: low estrogen, progestin unclear, anti-androgenic and anti-mineralcorticoid • Demulen 1/35: medium estrogen, high progestin, low androgen • Ortho-Cyclen, Ovcon-35, Modicon: medium estrogen, low progestin, low androgen • Ortho-Novum 1/50, Ortho-Novum 1/35: medium estrogen, medium progestin, medium androgen • Hormonal contraception. Pharmacist’s Letter/Prescriber’s Letter 2006; 22 (8):220809.
Comparison Cont’d. • High-dose Monophasic Pills • Ovcon-50: high estrogen, medium progestin, medium androgen • Ogestrel 0.5/50: high estrogen, high progestin, high androgen • Demulen 1/50: high estrogen, high progestin, medium/high androgen • Hormonal contraception. Pharmacist’s Letter/Prescriber’s Letter 2006; 22 (8):220809.
Comparison Cont’d. • Biphasic Pills • Mircette: low estrogen, high progestin, low androgen • Ortho-Novum 10/11: high estrogen, medium progestin, low/medium androgen • Hormonal contraception. Pharmacist’s Letter/Prescriber’s Letter 2006; 22 (8):220809.
Comparison Cont’d. • Triphasic Pills • Estrostep Fe: low estrogen, high progestin, medium androgen • Ortho Tri-Cyclen Lo: low estrogen, low progestin, low androgen • Cyclessa: low estrogen, high progestin, low androgen • Triphasil: medium estrogen, low progestin, low/medium androgen • Ortho Tri-Cyclen: medium estrogen, low progestin, low androgen • Tri-Norinyl, Ortho-Novum 7/7/7: medium estrogen, medium progestin, low/medium androgen • Hormonal contraception. Pharmacist’s Letter/Prescriber’s Letter 2006; 22 (8):220809.
Comparison Cont’d. • Extended-Cycle Pills • Seasonale • 84 days of active pills followed by 7-day pill-free interval • 4 menstrual cycles a year • Seasonique • 84 days of active pills followed by 7-day low-dose estrogen • Loestrin-24 Fe • 24 active pills followed by four placebo days, low estrogen/progestin ratio • Yaz • 24 active pills followed by four placebo days, low estrogen • Hormonal contraception. Pharmacist’s Letter/Prescriber’s Letter 2006; 22 (8):220809.
Comparison Cont’d. • Progestin-only Pills (“Mini-pill”) • Micronor, Nor-QD: low progestin • Emergency Contraception • Plan B: high progestin x 2 pills (levonorgestrel 0.75 mg each) • Women presenting w/in 72 hrs of unprotected intercourse or contraceptive failure (89% effective), consider for up to 5 days following unprotected intercourse • Hormonal contraception. Pharmacist’s Letter/Prescriber’s Letter 2006; 22 (8):220809.
Side Effects Hormonal contraception. Pharmacist’s Letter/Prescriber’s Letter 2006; 22 (8):220809.
Other benefits (lowered risk or incidence): • Dysmenorrhea • Iron deficiency anemia • Ectopic pregnancy (COC pill only) • Ovarian cysts (higher dose estrogen pills only) • Ovarian cancer • Endometrial cancer • Increased bone density • Acne • Ortho Tri-Cyclen and Estrostep FDA-labeled for treatment of acne* • Martin KA, Barbieri R, Up To Date: Overview of the use of estrogen-progestin contraceptives. Available online. (Accessed Jan 30 2007). • *Hormonal contraception. Pharmacist’s Letter/Prescriber’s Letter 2006; 22 (8):220809.
Absolute Contraindications • Known pregnancy • Breast or uterine cancer • Thromboembolic event or stroke • Hepatitis
Recent Happenings with the FDA • FOR IMMEDIATE RELEASEStatement January 23, 2007Media Inquiries: 301-827-6242 Consumer Inquiries: 888-INFO-FDA “FDA Statement on Effectiveness of Newer Birth Control Pills • Recent wire service stories about today's meeting of the FDA Reproductive Health Drugs Advisory Committee have created misperceptions about the effectiveness of newer generation hormonal contraceptives. • The stories inaccurately report that the products are significantly less effective at preventing pregnancy than those approved decades ago. In fact, the newer generation products are highly effective in preventing pregnancy. • The stories also mistakenly state that FDA called the meeting to discuss the need for higher standards of efficacy for the newer products. • In fact, as published in the Federal Register Notice announcing this meeting, the purpose of this two-day meeting is to discuss clinical trial designs that reflect the diversity of users of hormonal contraceptives, expectations for efficacy and safety, and user acceptability of the newer generation products, including cycle control.” Available at: http://www.fda.gov/bbs/topics/NEWS/2007/NEW01550.html
Efficacy • COC • FDA approval date: 1960, 2003 • 1-2 pregnancies expected per 100 women per year • POP • FDA approval date: 1973 • 2 pregnancies expected per 100 women per year • Seasonale • FDA approval date: 2003 • 1-2 pregnancies expected per 100 women per year • Birth Control Guide. Updated Dec. 2003. U.S. Food and Drug Administration. Available online at http://www.fda.gov/fdac/features/1997/babytabl.html. • % Women w/ unintended pregnancy w/in 1st year of use of COC/POP • Typical use: 8% • Perfect use: 0.3% Trussell J. Contraceptive efficacy. In Hatcher RA, Trussell J, Stewart F, Nelson A, Cates W, Guest F, Kowal D. Contraceptive Technology: Eighteenth Revised Edition. New York NY: Ardent Media, 2004.
Now, back to our patient • Healthy baby boy born 3-12-04 • Contraceptive efficacy: • Inherent efficacy of the method itself • Frequency of intercourse • Age of the woman • User competence and compliance
Increasing Efficacy: • Perfect Use • Use back-up contraception: • The first month starting the pill • Using antibiotics (tetracyclines, PCNs, cephalosporins), Rifampin, Anticonvulsants, St. John’s Wort • Missed pills • Changing pill formulation • Switching brand name to generic • 1984 law “that bioequivalent drug products are therapeutically equivalent and, therefore, interchangeable”* • *Food and Drug Administration: Center for Drug Evaluation and Research approved Drug Products with Therapeutic Equivalence Evaluations. Available online http://www.fda.gov/cder/ob/docs/preface/ecpreface.htm#Bioequivalent%20Drug%20Products