Monthly injectable contraceptives.

Abstract

Contraceptive researchers have found some monthly injectable contraceptives to be highly effective in suppressing ovulation. Clinical trials revealed that pregnancy rates for these injectable contraceptives range from 0-2.5%. Other advantages of monthly injectables include reduction in user error, paramedical personnel can administer them, absorption is not dependent on gastrointestinal function, production of no gastrointestinal symptoms, and rapid return to fertility. On the other hand, a major disadvantage is that the user must go to the clinic every 30 days for an injection. Nevertheless, interest in monthly injectable contraceptives is climbing because of their ability to cause regular monthly bleeding, unlike the long acting progestogen injectable contraceptives which often cause amenorrhea. This accounts for the main reason for discontinuation of the long acting injectables, especially in the 1st 6 months of use. They also cause a significant delay in the return to ovulation and fertility. The current high doses of steroids in monthly injectable formulations and their apparent accumulation in the body provide a basis for practitioners to continually monitor patients for risk factors, e.g. neoplasia, and side effects, e.g. amenorrhea and for researchers to always assess their safety, use and effectiveness.