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Medically reviewed by Militian Inessa Mesropovna, PharmD. Last updated on 09.04.2022
Attention! Information on this page is intended only for medical professionals! Information is collected in open sources and may contain significant errors! Be careful and double-check all the information on this page!
ORTHO MICRONOR® (0.35 mg norethindrone) Tablets are available in a DIALPAK® Tablet Dispenser
(NDC 0062-1411-16) containing 28 lime green, round, flat faced, beveled edge tablets, imprinted “ORTHO 0.35” on both sides.
STORAGE: Store at 25°C
Keep out of reach of children.
REFERENCE
McCann M, and Potter L. Progestin-Only Oral Contraceptives: A Comprehensive Review. Contraception, 50:60 (Suppl. 1), December 1994.
Truitt ST, Fraser A, Gallo ME, Lopez LM, Grimes DA and Schulz KF. Combined hormonal versus nonhormonal versus progestin-only contraception in lactation (Review). The Cochrane Collaboration. 2007, Issue 3.
Halderman, LD and Nelson AL. Impact of early postpartum administration of progestin-only hormonal contraceptives compared with nonhormonal contraceptives on short-term breast-feeding patterns. Am J Obstet Gynecol.; 186 (6):1250-1258.
Ostrea EM, Mantaring III JB, Silvestre MA. Drugs that affect the fetus and newborn infant via the placenta or breast milk. Pediatr Clin N Am; 51(2004): 539-579.
Cooke ID, Back DJ, Shroff NE: Norethisterone concentration in breast milk and infant and maternal plasma during ethynodiol diactetate administration. Contraception 1985; 31:611-21.
ORTHO-McNEIL, PHARMACEUTICAL, INC., Raritan, New Jersey 08869. REVISED June, 2008. FDA rev date: 6/20/2008
- Indications
Progestin-only oral contraceptives are indicated for the prevention of pregnancy. - Efficacy
If used perfectly, the first-year failure rate for progestin-only oral contraceptives is 0.5%. However, the typical failure rate is estimated to be closer to 5%, due to late or omitted pills. Table 1 lists the pregnancy rates for users of all major methods of contraception.
Table 1: Percentage of Women Experiencing an Unintended Pregnancy
During the First Year of Typical Use and the First Year of Perfect Use of Contraception
and the Percentage Continuing Use at the End of the First Year. United States.
| % of Women Experiencing an Unintended Pregnancy within the First Year of Use |
% of Women Continuing Use at One Year3 |
||
| Method(1) | Typical Use 1(2) | Perfect Use2(3) | (4) |
| Chance4 | 85 | 85 | |
| Spermicides5 | 26 | 6 | 40 |
| Periodic abstinence | 25 | 63 | |
| Calendar | 9 | ||
| Ovulation Method | 3 | ||
| Sympto-Thermal6 | 2 | ||
| Post-Ovulation | 1 | ||
| Cap7 | |||
| Parous Women | 40 | 26 | 42 |
| Nulliparous Women | 20 | 9 | 56 |
| Sponge | |||
| Parous Women | 40 | 20 | 42 |
| Nulliparous Women | 20 | 9 | 56 |
| Diaphragm7 | 20 | 6 | 56 |
| Withdrawal | 19 | 4 | |
| Condom8 | |||
| Female (Reality®) | 21 | 5 | 56 |
| Male | 14 | 3 | 61 |
| Pill | 5 | 71 | |
| Progestin Only | 0.5 | ||
| Combined | 0.1 | ||
| IUD | |||
| 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 |
| Norplant® and | 0.05 | 0.05 | 88 |
| Norplant-2® | |||
| Female Sterilization | 0.5 | 0.5 | 100 |
| Male Sterilization | 0.15 | 0.10 | 100 |
| Adapted from Hatcher et al, 1998, Ref. #
1. 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 highly effective, temporary method of contraception.10 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. 1 Among typical couples who initiate use of a method (not necessarily for the first time), the percentage who experience an accidental pregnancy during the first year if they do not stop use for any other reason. 2 Among couples who initiate 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. 3Among couples attempting to avoid pregnancy, the percentage who continue to use a method for one year. 4 The percents becoming pregnant 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 percent who would become pregnant within one year among women now relying on reversible methods of contraception if they abandoned contraception altogether. 5Foams, 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. 7With spermicidal cream or jelly. 8Without 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: OvralR (1 dose is 2 white pills), AlesseR (1 dose is 5 pink pills), NordetteR or LevlenR (1 dose is 2 light-orange pills), Lo/OvralR (1 dose is 4 white pills), TriphasilR or Tri-LevlenR (1 dose is 4 yellow pills). 10 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 six months of age. |
ORTHO MICRONOR® (norethindrone) Tablets have not been studied for and are not indicated for use in emergency contraception.
To achieve maximum contraceptive effectiveness, ORTHO MICRONOR® (norethindrone) must be taken exactly as directed. One tablet is taken every day, at the same time. Administration is continuous, with no in terruption between pill packs. See Detailed Patient Labeling for detailed instruction.
Progestin-only oral contraceptives (POPs) should not be used by women who currently have the following conditions:
- Known or suspected pregnancy
- Known or suspected carcinoma of the breast
- Undiagnosed abnormal genital bleeding
- Hypersensitivity to any component of this product
- Benign or malignant liver tumors
- Acute liver disease
WARNINGS
Cigarette smoking increases the risk of serious cardiovascular disease. Women who use oral contraceptives should be strongly advised not to smoke.
ORTHO MICRONOR® (norethindrone) does not contain estrogen and, therefore, this insert does not discuss the serious health risks that have been associated with the estrogen component of combined oral contraceptives (COCs). The healthcare professional is referred to the prescribing information of combined oral contraceptives for a discussion of those risks. The relationship between progestin-only oral contraceptives and these risks is not fully defined. The healthcare professional should remain alert to the earliest manifestation of symptoms of any serious disease and discontinue oral contraceptive therapy when appropriate.
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. Healthcare professionals 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.
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.
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.
Carcinoma of the Breast and Reproductive Organs
Some epidemiological 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 increases the risk.
A meta-analysis of 54 studies found a small increase in the frequency of having breast cancer diagnosed for women who were currently using combined oral contraceptives or had used them within the past ten years.
This increase in the frequency of breast cancer diagnosis, within ten years of stopping use, was generally accounted for by cancers localized to the breast. There was no increase in the frequency of having breast cancer diagnosed ten or more years after cessation of use.
Women with breast cancer should not use oral contraceptives because the role of female hormones 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.
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 have shown an increased risk of developing hepatocellular carcinoma in combined oral contraceptive users. However, these cancers are rare in the U.S. There is insufficient data to determine whether POPs increase the risk of developing hepatic neoplasia.
PRECAUTIONS
General
Patients should be counseled that this product does not protect against HIV infection (AIDS) and other sexually transmitted diseases.
Physical Examination and Follow up
It is considered good medical practice for sexually active women using oral contraceptives to have annual history and physical examinations. The physical examination may be deferred until after initiation of oral contraceptives if requested by the woman and judged appropriate by the healthcare professional.
Carbohydrate and Lipid Metabolism
Some users may experience slight deterioration in glucose tolerance, with increases in plasma insulin but women with diabetes mellitus who use progestin-only oral contraceptives do not generally experience changes in their insulin requirements. Nonetheless, prediabetic and diabetic women in particular should be carefully monitored while taking POPs.
Lipid metabolism is occasionally affected in that HDL, HDL2, and apolipoprotein A-I and A-II may be decreased; hepatic lipase may be increased. There is usually no effect on total cholesterol, HDL3, LDL, or VLDL.
Carcinogenesis
See WARNINGS section.
Pregnancy
Many studies have found no effects on fetal development associated with long-term use of contraceptive doses of oral progestins. The few studies of infant growth and development that have been conducted have not demonstrated significant adverse effects. It is nonetheless prudent to rule out suspected pregnancy before initiating any hormonal contraceptive use.
Nursing Mothers
In general, no adverse effects have been found on breastfeeding performance or on the health, growth, or development of the infant. However, isolated post-marketing cases of decreased milk production have been reported. Small amounts of progestins pass into the breast milk of nursing mothers, resulting in detectable steroid levels in infant plasma.
Pediatric Use
Safety and efficacy of ORTHO MICRONOR® (norethindrone) Tablets have been established in women of reproductive age. Safety and efficacy are expected to be the same for postpubertal adolescents under the age of 16 and for users 16 years and older. Use of this product before menarche is not indicated.
Fertility Following Discontinuation
The limited available data indicate a rapid return of normal ovulation and fertility following discontinuation of progestin-only oral contraceptives.
Headache
The onset or exacerbation of migraine or development of severe headache with focal neurological symptoms which is recurrent or persistent requires discontinuation of progestin-only contraceptives and evaluation of the cause.
Information for the Patient
- See “Detailed Patient Labeling” for detailed information.
- Counseling issues
The following points should be discussed with prospective users before prescribing progestin-only oral contraceptives:
- The necessity of taking pills at the same time every day, including throughout all bleeding episodes.
- The need to use a backup method such as condoms and spermicides for the next 48 hours whenever a progestin-only oral contraceptive is taken 3 or more hours late.
- The potential side effects of progestin-only oral contraceptives, particularly menstrual irregularities.
- The need to inform the healthcare professional of prolonged episodes of bleeding, amenorrhea or severe abdominal pain.
- The importance of using a barrier method in addition to progestin-only oral contraceptives if a woman is at risk of contracting or transmitting STDs/HIV.
SIDE EFFECTS
Adverse reactions reported with the use of POPs include:
- Menstrual irregularity is the most frequently reported side effect.
- Frequent and irregular bleeding are common, while long duration of bleeding episodes and amenorrhea are less likely.
- Headache, breast tenderness, nausea, and dizziness are increased among progestin-only oral contraceptive users in some studies.
- Androgenic side effects such as acne, hirsutism, and weight gain occur rarely.
DRUG INTERACTIONS
The effectiveness of progestin-only pills is reduced by hepatic enzyme-inducing drugs such as the anticonvulsants phenytoin, carbamazepine, and barbiturates, and the antituberculosis drug rifampin. No significant interaction has been found with broad-spectrum antibiotics.
Interactions with Laboratory Tests
The following endocrine tests may be affected by progestin-only oral contraceptive use:
- Sex hormone-binding globulin (SHBG) concentrations may be decreased.
- Thyroxine concentrations may be decreased, due to a decrease in thyroid binding globulin (TBG).
Many studies have found no effects on fetal development associated with long-term use of contraceptive doses of oral progestins. The few studies of infant growth and development that have been conducted have not demonstrated significant adverse effects. It is nonetheless prudent to rule out suspected pregnancy before initiating any hormonal contraceptive use.
Adverse reactions reported with the use of POPs include:
- Menstrual irregularity is the most frequently reported side effect.
- Frequent and irregular bleeding are common, while long duration of bleeding episodes and amenorrhea are less likely.
- Headache, breast tenderness, nausea, and dizziness are increased among progestin-only oral contraceptive users in some studies.
- Androgenic side effects such as acne, hirsutism, and weight gain occur rarely.
There have been no reports of serious ill effects from overdosage, including ingestion by children.
