Known or suspected pregnancy is a contraindication of levonorgestrel as an emergency contraceptive. Overdose of levonorgestrel as an emergency contraceptive has not been described. Domperidone has been studied as a potential hormonal contraceptive to prevent pregnancy in women. An occlusive pessary is generally used in combination with spermicide as a contraceptive. Stopping oral contraceptive pills may be recommended. The plant may also have functioned as a contraceptive and abortifacient. Such preparations were used in early combined oral contraceptive pills. This effect can be even more pronounced in women taking oral contraceptive medication. A number of contraceptive methods are available to prevent unwanted pregnancy. The breasts can also become enlarged from adverse side effects of combined oral contraceptive pills. Depo Provera is an injection that provides three months of contraceptive protection. The most common reason is a vasectomy done to induce contraceptive sterility. Contraceptive use is permitted for birth control. Exogenous androgen supplements can be used as a male contraceptive. Ormeloxifene may be used as a weekly oral contraceptive.