Lead investigator David F. Archer, M.D., professor of obstetrics and gynecology at Eastern Virginia Medical School, said that the medicine, called Lybrel, was taken every day for a year and halted periods in more than half of the 2,000 women who used it.
Lybrel is a formulation marketed by Wyeth Pharmaceuticals.
The landmark study says that it is the first pill specifically designed to end the fertility cycle.
According to Medical News Today, Archer said, "It is felt that the relief of menstrual cycle symptoms during continuous use of the contraceptive is a significant improvement in the quality of life."
The researchers conducted the study on 92 sites in North America using a birth-control pill consisting of 20 micrograms of ethinyl estradiol and 90 micrograms of levonorgestrel. Healthy and sexually active women between 18 and 49 years old were given a continuous regimen without any breaks.
According to the researchers, during the course of the study of more than 18 months the median and mean number of bleeding days decreased progressively.
Of the 2,134 subjects enrolled, 79 percent reported an absence of bleeding after one year while 58.7 percent reported cessation of menstrual cycle.
The results concluded that the continuous-use, low-dose regimen was safe and as effective as traditional oral contraceptives.
