ABSTRACT
The Combined Oral Contraceptives (COC) pills currently available in the United Kingdom. They all contain estrogen (ethinylestradiol [EE] aside from three with estradiol), combined with one of nine progestogens. They are monophasic or multiphasic and can also be taken continuously or in a tricycle regimen. Aside from secondary contraceptive effects on the cervical mucus and to impede implantation, COCs like all CHCs primarily prevent ovulation. This makes the method highly effective in “perfect” use, but it removes the normal menstrual cycle and in the standard 21/7 regimen replaces it with a cycle that is user-produced and based only on the end organ. COC use increases the relative risk of benign adenoma or hamartoma, either of which can cause pain or rarely a haemo-peritoneum. Most reported cases have been in long-term users of relatively high-dose pills that are now not used. Moreover, the background incidence is so small that the COC-attributable risk is minimal.
