Contraception - Emergency contraception (EC)

EC is birth control used to prevent pregnancy after
known or suspected failure of contraception or
unprotected intercourse, including sexual assault.
A national survey of women in the USA reported that
even though two-thirds of women were aware of EC,
only 6% reported ever having used it.16
EC in the USA continues to provoke controversy
because of ethical perspectives on prevention and
termination of pregnancy, and concerns about the
impact of over-the-counter availability.17 Even so, in
August 2006, the FDA approved the sale of progestinonly
EC without a prescription to women and men
18 years of age and older. Some clinicians may still
use estrogen/progestin containing oral contraceptives
as EC because of their availability.
EC hinders or delays ovulation, prevents fertilization,
and may affect implantation. It does not interrupt
or disrupt an already established pregnancy.
On average, eight of 70 women will become pregnant
from a single act of unprotected intercourse.
Progestin containing EC results in 1 pregnancy per
70 women, (about 89% effective) depending upon
its timing in relation to unprotected intercourse.18 If
70 women used combination estrogen/progestin as
EC, two would become pregnant; if 700 women had
an IUD placed followed unprotected intercourse,
only one would become pregnant.
The World Health Organization regards the only
contraindication to either combination estrogen/
progestin EC or the progestin-only EC is a known
pregnancy, primarily because the treatment will not
work in already pregnant patients.
There have been sporadic case reports of ectopic
pregnancies following EC. Patients with a history of
salpingitis or ectopic pregnancy should be counseled
regarding the potentially increased risk of an ectopic
pregnancy regardless of EC use or non-use. Progestinonly
EC does not increase the risk of ectopic pregnancy;
there is no evidence demonstrating EC is
teratogenic.
For individuals with chronic health conditions
in which estrogen containing OCs are contraindicated,
combination EC may still be offered because the duration of use is extremely short. However,
progestin-only regimens may be prefered for those
with with known hypercoagulable states, such as a
history of blood clots or hereditary hypercoagulopathies
or thrombophilias.
Because pregnancy may itself increase the risk of
adverse outcomes in women with these health conditions,
contraceptive benefit and availability of ECs
may outweigh any risks.
Concurrent use of certain medications such as
some antiepileptic drugs, St John’s wort, medications
to treat human immunodeficiency virus, the antibiotic
rifampin, and the antifungal griseofulvin may
reduce the efficacy of OCs and, thus, potentially combination
EC, but not affect efficacy of the progestinonly
EC.
Currently available methods of EC are listed in
Table 7.5, and include oral hormones similar to those
available in many OCPs , the progestin-only EC, and
the copper T intrauterine device.

Posted in: Contraception,Health