ate use of a method (not necessarily for the first time), and who use it perfectly (both consistently and correctly), the percentage who experience an accidental pregnancy during the first year if they do not stop use for any other reason. 3 among couples attempting to avoid pregnancy, the percentage who continue to use a method for one year. 4 the percentage of women becoming pregnant noted in columns (2) and (3) are based on data from populations where contraception is not used and from women who cease using contraception in order to become pregnant. among such populations, about 89% become pregnant within one year. this estimate was lowered slightly (to 85%) to represent the percentage that would become pregnant within one year among women now relying on reversible methods of contraception if they abandoned contraception altogether. 5 foams, creams, gels, vaginal suppositories, and vaginal film. 6 cervical mucus (ovulation) method supplemented by calendar in the pre-ovulatory and basal body temperature in the post-ovulatory phases. 7 with spermicidal cream or jelly. 8 without spermicides. 9 the treatment schedule is one dose within 72 hours after unprotected intercourse, and a second dose 12 hours after the first dose. the food and drug administration has declared the following brands of oral contraceptives to be safe and effective for emergency contraception: ovral ® (1 dose is 2 white pills), alesse ® (1 dose is 5 pink pills), nordette ® or levlen ® (1 dose is 4 yellow pills). 1 0 however, to maintain effective protection against pregnancy, another method of contraception must be used as soon as menstruation resumes, the frequency or duration of breastfeeds is reduced, bottle feeds are introduced, or the baby reaches 6 months of age. method typical use 1 perfect use 2 ( 1 ) ( 2 ) ( 3 ) ( 4 ) chance 4 85 85 spermicides 5 26 6 40 periodic abstinence 25 63 calendar 9 ovulation method 3 sympto-thermal 6 2 post-ovulation 1 cap 7 parous women 40 26 42 nulliparous women 20 9 56 sponge parous women 40 20 42 nulliparous women 20 9 56 diaphragm 7 20 6 56 withdrawal 19 4 condom 8 female (reality) 21 5 56 male 14 3 61 pill 5 71 progestin only 0.5 combined 0.1 iuds progesterone t 2.0 1.5 81 copper t380a 0.8 0.6 78 lng 20 0.1 0.1 81 depo-provera ® 0.3 0.3 70 levonorgestrel implants (norplant ® ) 0.05 0.05 88 female sterilization 0.5 0.5 100 male sterilization 0.15 0.10 100 emergency contraceptive pills : treatment initiated within 72 hours after unprotected intercourse reduces the risk of pregnancy by at least 75%. 9 lactational amenorrhea method : lam is a highly effective, temporary method of contraception. 1 0 source : trussell, j, contraceptive efficacy. in: hatcher ra, trussell j, stewart f, cates w, stewart gk, kowal d, guest f, contraceptive technology: seventeenth revised edition. new york, ny: irvington publishers, 1998.

manifestation of symptoms of any serious disease and discontinue oral contraceptive therapy when appropriate. 1. ectopic pregnancy the incidence of ectopic pregnancies for progestin-only oral contraceptive users is 5 per 1000 woman-years. up to 10% of pregnancies reported in clinical studies of progestin-only oral contraceptive users are extrauterine. although symptoms of ectopic pregnancy should be watched for, a history of ectopic pregnancy need not be considered a contraindication to use of this contraceptive method. health providers should be alert to the possibility of an ectopic pregnancy in women who become pregnant or complain of lower abdominal pain while on progestin-only oral contraceptives. 2. delayed follicular atresia/ovarian cysts if follicular development occurs, atresia of the follicle is sometimes delayed, and the follicle may continue to grow beyond the size it would attain in a normal cycle. generally these enlarged follicles disappear spontaneously. often they are asymptomatic; in some cases they are associated with mild abdominal pain. rarely they may twist or rupture, requiring surgical intervention. 3. irregular genital bleeding irregular menstrual patterns are common among women using progestin-only oral contraceptives. if genital bleeding is suggestive of infection, malignancy or other abnormal conditions, such nonpharmacologic causes should be ruled out. if prolonged amenorrhea occurs, the possibility of pregnancy should be evaluated. 4. carcinoma of the breast and reproductive organs some epidemiologic studies of oral contraceptive users have reported an increased relative risk of developing breast cancer, particularly at a younger age and apparently related to duration of use. these studies have predominantly involved combined oral contraceptives and there is insufficient data to determine whether the use of pops similarly increase the risk. women with breast cancer should not use oral contraceptives because the role of female hormone in breast cancer has not been fully determined. some studies suggest that oral contraceptive use has been associated with an increase in the risk of cervical intraepithelial neoplasia in some populations of women. however, there continues to be controversy about the extent to which such findings may be due to differences in sexual behavior and other factors. there is insufficient data to determine whether the use of pops increases the risk of developing cervical intraepithelial neoplasia. 5. hepatic neoplasia benign hepatic adenomas are associated with combined oral contraceptive use, although the incidence of benign tumors is rare in the united states. rupture of benign, hepatic adenomas may cause death through intra-abdominal hemorrhage. studies from britain and the u.s. have shown an increased risk of developing hepatocellular carcinoma in combined oral contraceptive users. however, these cancers are rare. there is insufficient data to determine whether pops increase the risk of developing hepatic neoplasia.

generally occurred within 1 hour (mean) of tablet administration, ranging from 0.5 to 2 hours. the mean (sd) c avg was 885 (250) pg/ml, however, the mean concentration at 24 hrs was 130 (47) pg/ml. table 1 provides summary statistics of the pharmacokinetic parameters associated with single dose norethindrone tablets administration. table 1: mean ± sd pharmacokinetic parameters following single dose administration of norethindrone tablets in 12 healthy female subjects under fasting conditions pharmacokinetic parameter norethindrone 0 . 35 mg t m a x (hr) 1.2 ± 0.5 c m a x (pg/ml) 4817 ± 1533 auc ( 0 - 4 8 ) (pg.h/ml) 21233 ± 6002 t 1 / 2 (h) 7.7 ± 0.5 the food effect on the rate and extent of norethindrone absorption after norethindrone tablet administration has not been evaluated. distribution following oral administration, norethindrone is 36% bound to sex hormone-binding globulin (shbg) and 61% bound to albumin. volume of distribution of norethindrone is approximately 4 l/kg. metabolism norethindrone undergoes extensive biotransformation, primarily via reduction, followed by sulfate and glucuronide conjugation; less than 5% of a norethindrone dose is excreted unchanged; greater than 50% and 20-40% of a dose is excreted in urine and feces, respectively. the majority of metabolites in the circulation are sulfate, with glucuronides accounting for most of the urinary metabolites. excretion plasma clearance rate for norethindrone has been estimated to be approximately 600 l/day. norethindrone is excreted in both urine and feces, primarily as metabolites. the mean terminal elimination half-life of norethindrone following single dose administration of norethindrone tablet is approximately 8 hours. figure 1 mean sd norethindrone plasma concentrations following uforla administration