Slide 2
Most COCs are based on a 28-day cycle. In some packs, 21
pills contain estrogen and progestin and the 7 additional pills contain no hormones. Other
packs contain only 21 pills and the woman does not take any pills for 7 days. With both
types of packs, the 7 days without hormones allow for menses to occur. The woman is still
protected against pregnancy during this time.
Biphasic and triphasic pills are designed to more closely mimic the natural hormonal
changes during a woman’s cycle. They contain a lower total hormone dose but have not
been found to perform differently than monophasic pills.
Slide 7
There is a good deal of evidence to suggest that
COCs reduce the risk of developing ovarian cancer. By suppressing ovulation or altering
hormonal levels throughout the menstrual cycle, it appears that COCs alter the conditions
that favor development of ovarian cancer. COCs may also reduce the opportunity for cells
to mutate by decreasing the number of ovarian cell divisions. Finally, a 1998 animal study
suggests that progestin may cause the death of damaged ovarian cells before they become
cancerous.
The magnitude of the reduction in risk appears to depend on the duration of pill
use—those women using the pill for a longer period of time (e.g., > 5 years) have
a larger reduction in risk. Studies also suggest that the protective effect lasts for at
least 10 to 15 years.
Source: Herbst AL. 1994. OCs and genital malignancies. Dialogues in
Contraception 4(3):5-7.
Slide 8
There is no evidence that COCs lead to a higher
incidence of breast cancer. COC use has been related to a higher risk of being diagnosed
with breast cancer and it is believed that this may be the result of acceleration of the
cancer by the COCs. Cancers diagnosed in COC users are generally at an earlier stage than
those diagnosed in non-COC users and are thus likely to have a better prognosis.
Slide 12
Women who have had trouble remembering to take pills in
the past should be counseled about the need to take the pill at the same time every day.
The healthcare worker may want to suggest that the woman take the pills at meal time or
just before going to bed. If she does not feel that she will be able to remember to take
the pill each day, the client should be helped to choose a more appropriate method.
