Injectable contraceptives progestins

Lunelle. Lunelle is a newer injectable contraceptive formulation that combines the effects of a progestin, medroxy-... 

As of 1994, there were approximately 47 progestin-containing contraceptive dmg formulations sold in the United States for use as oral contraceptives (Table 3). In addition, there are three nonoral contraceptive formulations containing progestins ie, one injectable (Depo-Provera), one as an intrauterine device (lUD) (Progestasert), and one implantable (Norplant). Of the oral formulations, all but two also contain an estrogen component, ethynylestradiol. 

Progestin-only contraceptives (Fig. 4) contain low-doses of progestins (e.g. 350 pg norethindrone or 75 pg norgestrel) that have to be administered daily without interruption. The lowest expected failure rate during the first year of use is 0.5%, while the typical failure rate amounts to 3%. Subdermal implants of norgestrel (216 mg) for sustained release provides for long-term (for up to 5 years) contraceptive effects characterized by failure rates of only 0.05%. Reliable contraception for 3 months can be achieved by an intramuscular injection of a crystalline suspension of 150 mg medroxyprogesterone acetate (Fig. 3) (failure rate 0.3%). 

Women who particularly benefit from progestin-only methods, including minipills, are those who are breast-feeding, those who are intolerant to estrogens, and those with concomitant medical conditions in which estrogen is not recommended. Also injectable and implantable contraceptives are beneficial for women with compliance issues. 

In 1992, the US FDA approved a long-acting contraceptive device containing synthetic progestin medroxyprogesterone acetate (MPA) hormones. Manufactured by Pfizer, Inc., it is sold under the trade name Depo-Provera . It is typically injected into a woman s buttocks or upper arm, and renders her temporarily sterile for up to 3 months. ... 

Only one implantable contraceptive preparation is available at present. Norgestrel, also utilized as the progestin component of some oral contraceptive preparations, is an effective suppressant of ovulation when it is released from subcutaneous implants. Intramuscular injection of large doses of medroxyprogesterone also provides contraceptive action of long duration. 

Commonly used methods of reversible contraception include oral and transdermal contraceptives, long-acting injectable estrogens and progestins, implantable progestins, condoms, spermicides, withdrawal, the diaphragm, periodic abstinence, and the intrauterine device. These methods differ in their relative effectiveness, safety, and patient acceptability." ... 

Women receiving anticonvulsants for a seizure disorder require special attention with regard to hormonal contraception. Giving a hormonal contraceptive concomitantly with phenobarbital, carba-mazepine, or phenytoin reduces the contraceptive s efficacy, and many anticonvulsants (e.g., phenytoin) are known teratogens. The use of condoms in conjunction with high-estrogen OCs, injectable progestin-only contraceptives, or intrauterine devices may be considered for these women. ... 

Another type of contraception is injectable progestin, a synthetic form of progesterone. Depo-Provera is a product that is injected by a healthcare professional into the arm muscle or buttocks every 3 months. 

---