Warnings for Kalliga
Cigarette smoking increases the risk of serious
cardiovascular events from combination oral contraceptive use. This risk increases
with age, particularly in women over 35 years of age, and with the number of
cigarettes smoked. For this reason, combination oral contraceptives, including
Kalliga™, should not be used by women who are over 35 years of age and smoke.
The use of oral contraceptives is associated with
increased risks of several serious conditions including myocardial infarction,
thromboembolism, stroke, hepatic neoplasia, and gallbladder disease, although
the risk of serious morbidity or mortality is very small in healthy women
without underlying risk factors. The risk of morbidity and mortality increases
significantly in the presence of other underlying risk factors such as
hypertension, hyperlipidemias, obesity and diabetes.
Practitioners prescribing oral contraceptives should be
familiar with the following information relating to these risks.
The information contained in this package insert is
principally based on studies carried out in patients who used oral
contraceptives with formulations of higher doses of estrogens and progestogens
than those in common use today. The effect of long-term use of the oral
contraceptives with formulations of lower doses of both estrogens and
progestogens remains to be determined.
Throughout this labeling, epidemiological studies reported
are of two types: retrospective or case control studies and prospective or
cohort studies. Case control studies provide a measure of the relative risk of
a disease, namely, a ratio of the incidence of a disease among oral
contraceptive users to that among nonusers. The relative risk does not provide
information on the actual clinical occurrence of a disease. Cohort studies
provide a measure of attributable risk, which is the difference in the
incidence of disease between oral contraceptive users and nonusers. The
attributable risk does provide information about the actual occurrence of a
disease in the population (Adapted from refs. 2 and 3 with the author's
permission). For further information, the reader is referred to a text on
epidemiological methods.
Thromboembolic Disorder And Other Vascular Problems
Thromboembolism
An increased risk of thromboembolic and thrombotic
disease associated with the use of oral contraceptives is well established. Case
control studies have found the relative risk of users compared to non-users to
be 3 for the first episode of superficial venous thrombosis, 4 to 11 for deep
vein thrombosis or pulmonary embolism, and 1.5 to 6 for women with predisposing
conditions for venous thromboembolic disease.2,3,19 to 24 Cohort
studies have shown the relative risk to be somewhat lower, about 3 for new
cases and about 4.5 for new cases requiring hospitalization.25 The
risk of thromboembolic disease associated with oral contraceptives gradually
disappears after combined oral contraceptive (COC) use is stopped.2 VTE risk
is highest in the first year of use and when restarting hormonal contraception
after a break of four weeks or longer.
Several epidemiologic studies indicate that third
generation oral contraceptives, including those containing desogestrel, are
associated with a higher risk of venous thromboembolism than certain second
generation oral contraceptives. In general, these studies indicate an
approximate 2-fold increased risk, which corresponds to an additional 1 to 2
cases of venous thromboembolism per 10,000 women-years of use. However, data
from additional studies have not shown this 2-fold increase in risk.
A two- to four-fold increase in relative risk of
post-operative thromboembolic complications has been reported with the use of
oral contraceptives.9 The relative risk of venous thrombosis in
women who have predisposing conditions is twice that of women without such
medical conditions.26 If feasible, oral contraceptives should be
discontinued at least four weeks prior to and for two weeks after elective
surgery of a type associated with an increase in risk of thromboembolism and
during and following prolonged immobilization. Since the immediate postpartum
period is also associated with an increased risk of thromboembolism, oral
contraceptives should be started no earlier than four weeks after delivery in
women who elect not to breastfeed.
Myocardial Infarction
An increased risk of myocardial infarction has been
attributed to oral contraceptive use. This risk is primarily in smokers or
women with other underlying risk factors for coronary artery disease such as
hypertension, hypercholesterolemia, morbid obesity, and diabetes. The relative
risk of heart attack for current oral contraceptive users has been estimated to
be two to six.4 to 10 The risk is very low in women under the age of
30.
Smoking in combination with oral contraceptive use has
been shown to contribute substantially to the incidence of myocardial
infarctions in women in their mid-thirties or older with smoking accounting for
the majority of excess cases.11 Mortality rates associated with
circulatory disease have been shown to increase substantially in smokers,
especially in those 35 years of age and older and in nonsmokers over the age of
40 among women who use oral contraceptives. (See Figure 1.)
Figure 1: Circulatory Disease Mortality Rates per
100,000 Women-Years by Age, Smoking Status and Oral Contraceptive Use
Oral contraceptives may compound the effects of
well-known risk factors, such as hypertension, diabetes, hyperlipidemias, age
and obesity.13 In particular, some progestogens are known to decrease
HDL cholesterol and cause glucose intolerance, while estrogens may create a
state of hyperinsulinism.14 to 18 Oral contraceptives have been
shown to increase blood pressure among users.
Similar effects on risk factors have been associated with an increased risk of
heart disease. Oral contraceptives must be used with caution in women with
cardiovascular disease risk factors.
There is some evidence that the risk of myocardial
infarction associated with oral contraceptives is lower when the progestogen
has minimal androgenic activity than when the activity is greater. Receptor
binding and animal studies have shown that desogestrel or its active metabolite
has minimal androgenic activity (see CLINICAL PHARMACOLOGY), although these
findings have not been confirmed in adequate and well-controlled clinical
trials.
Cerebrovascular Diseases
Oral contraceptives have been shown to increase both the
relative and attributable risks of cerebrovascular events (thrombotic and
hemorrhagic strokes), although, in general, the risk is greatest among older
( > 35 years), hypertensive women who also smoke. Hypertension was found to be
a risk factor for both users and nonusers, for both types of strokes, and
smoking interacted to increase the risk of stroke.27 to 29
In a large study, the relative risk of thrombotic strokes
has been shown to range from 3 for normotensive users to 14 for users with
severe hypertension.30 The relative risk of hemorrhagic stroke is
reported to be 1.2 for non-smokers who used oral contraceptives, 2.6 for
smokers who did not use oral contraceptives, 7.6 for smokers who used oral
contraceptives, 1.8 for normotensive users and 25.7 for users with severe
hypertension.30 The attributable risk is also greater in older
women.3
Dose-Related Risk Of Vascular Disease From Oral
Contraceptives
A positive association has been observed between the
amount of estrogen and progestogen in oral contraceptives and the risk of
vascular disease.31 to 33 A decline in serum high density lipoproteins
(HDL) has been reported with many progestational agents.14 to 16 A
decline in serum high density lipoproteins has been associated with an
increased incidence of ischemic heart disease. Because estrogens increase HDL
cholesterol, the net effect of an oral contraceptive depends on a balance
achieved between doses of estrogen and progestogen and the nature and absolute
amount of progestogens used in the contraceptives. The amount of both hormones
should be considered in the choice of an oral contraceptive.
Minimizing exposure to estrogen and progestogen is in
keeping with good principles of therapeutics. For any particular
estrogen/progestogen combination, the dosage regimen prescribed should be one
which contains the least amount of estrogen and progestogen that is compatible
with a low failure rate and the needs of the individual patient. New acceptors
of oral contraceptive agents should be started on preparations containing the
lowest estrogen content which is judged appropriate for the individual patient.
Persistence Of Risk Of Vascular Disease
There are two studies which have shown persistence of
risk of vascular disease for ever-users of oral contraceptives. In a study in
the United States, the risk of developing myocardial infarction after
discontinuing oral contraceptives persists for at least 9 years for women 40 to
49 years old who had used oral contraceptives for five or more years, but this
increased risk was not demonstrated in other age groups.8 In another
study in Great Britain, the risk of developing cerebrovascular disease
persisted for at least 6 years after discontinuation of oral contraceptives,
although excess risk was very small.34 However, both studies were
performed with oral contraceptive formulations containing 0.05 mg or higher of
estrogens.
Estimates Of Mortality From Contraceptive Use
One study gathered data from a variety of sources which
have estimated the mortality rate associated with different methods of
contraception at different ages (Table 2). These estimates include the combined
risk of death associated with contraceptive methods plus the risk attributable
to pregnancy in the event of method failure. Each method of contraception has
its specific benefits and risks. The study concluded that with the exception of
oral contraceptive users 35 and older who smoke and 40 and older who do not
smoke, mortality associated with all methods of birth control is low and below
that associated with childbirth.
The observation of an increase in risk of mortality with
age for oral contraceptive users is based on data gathered in the 1970's.35
Current clinical recommendation involves the use of lower estrogen dose
formulations and a careful consideration of risk factors. In 1989, the
Fertility and Maternal Health Drugs Advisory Committee was asked to review the
use of oral contraceptives in women 40 years of age and over. The Committee
concluded that although cardiovascular disease risk may be increased with oral
contraceptive use after age 40 in healthy non-smoking women (even with the
newer low-dose formulations), there are also greater potential health risks
associated with pregnancy in older women and with the alternative surgical and
medical procedures which may be necessary if such women do not have access to
effective and acceptable means of contraception. The Committee recommended that
the benefits of low-dose oral contraceptive use by healthy non-smoking women
over 40 may outweigh the possible risks.
Of course, older women, as all women who take oral
contraceptives, should take an oral contraceptive which contains the least
amount of estrogen and progestogen that is compatible with a low failure rate
and individual patient needs.
Table 2: ANNUAL NUMBER OF BIRTH-RELATED OR
METHOD-RELATED DEATHS ASSOCIATED WITH CONTROL OF FERTILITY PER 100,000
NONSTERILE WOMEN, BY FERTILITY CONTROL METHOD ACCORDING TO AGE
| Method of control and outcome |
15 to 19 |
20 to 24 |
25 to 29 |
30 to 34 |
35 to 39 |
40 to 44 |
| No fertility-control methods* |
7 |
7.4 |
9.1 |
14.8 |
25.7 |
28.2 |
| Oral contraceptives non-smoker† |
0.3 |
0.5 |
0.9 |
1.9 |
13.8 |
31.6 |
| Oral contraceptives smoker† |
2.2 |
3.4 |
6.6 |
13.5 |
51.1 |
117.2 |
| IUD† |
0.8 |
0.8 |
1 |
1 |
1.4 |
1.4 |
| Condom* |
1.1 |
1.6 |
0.7 |
0.2 |
0.3 |
0.4 |
| Diaphragm/spermicide* |
1.9 |
1.2 |
1.2 |
1.3 |
2.2 |
2.8 |
| Periodic abstinence* |
2.5 |
1.6 |
1.6 |
1.7 |
2.9 |
3.6 |
Adapted from H.W. Ory, ref. #35.
*Deaths are birth-related
†Deaths are method-related |
Carcinoma Of The Reproductive Organs And Breasts
Numerous epidemiological studies have been performed on
the incidence of breast, endometrial, ovarian, and cervical cancer in women
using oral contraceptives.
The risk of having breast cancer diagnosed may be
slightly increased among current and recent users of combined oral
contraceptives (COC). However, this excess risk appears to decrease over time
after COC discontinuation and by 10 years after cessation the increased risk
disappears. Some studies report an increased risk with duration of use while other
studies do not and no consistent relationships have been found with dose or
type of steroid. Some studies have found a small increase in risk for women who
first use COCs before age 20. Most studies show a similar pattern of risk with
COC use regardless of a woman's reproductive history or her family breast
cancer history.
Breast cancers diagnosed in current or previous oral
contraceptive users tend to be less clinically advanced than in nonusers.
Women who currently have or have had breast cancer should
not use oral contraceptives because breast cancer is usually a
hormonally-sensitive tumor.
Some studies suggest that oral contraceptive use has been
associated with an increase in the risk of cervical intraepithelial neoplasia
in some populations of women.45 to 48 However, there continues to be
controversy about the extent to which such findings may be due to differences
in sexual behavior and other factors.
In spite of many studies of the relationship between oral
contraceptive use and breast and cervical cancers, a cause-and-effect
relationship has not been established.
Hepatic Neoplasia
Benign hepatic adenomas are associated with oral
contraceptive use, although the incidence of benign tumors is rare in the
United States. Indirect calculations have estimated the attributable risk to be
in the range of 3.3 cases/100,000 for users, a risk that increases after four
or more years of use especially with oral contraceptives of higher dose.49
Rupture of benign, hepatic adenomas may cause death through intra-abdominal
hemorrhage.
Studies from Britain have shown an increased risk of
developing hepatocellular carcinoma in long-term ( > 8 years) oral
contraceptive users. However, these cancers are extremely rare in the U.S. and
the attributable risk (the excess incidence) of liver cancers in oral
contraceptive users approaches less than one per million users.
Ocular Lesions
There have been clinical case reports of retinal
thrombosis associated with the use of oral contraceptives. Oral contraceptives
should be discontinued if there is unexplained partial or complete loss of
vision; onset of proptosis or diplopia; papilledema; or retinal vascular
lesions. Appropriate diagnostic and therapeutic measures should be undertaken
immediately.
Oral Contraceptive Use Before Or During Early Pregnancy
Extensive epidemiological studies have revealed no
increased risk of birth defects in women who have used oral contraceptives
prior to pregnancy.56 to 57 The majority of recent studies also do
not indicate a teratogenic effect, particularly in so far as cardiac anomalies
and limb reduction defects are concerned,55,56,58,59 when oral
contraceptives are taken inadvertently during early pregnancy.
The administration of oral contraceptives to induce
withdrawal bleeding should not be used as a test for pregnancy. Oral
contraceptives should not be used during pregnancy to treat threatened or
habitual abortion.
It is recommended that for any patient who has missed two
consecutive periods, pregnancy should be ruled out. If the patient has not
adhered to the prescribed schedule, the possibility of pregnancy should be
considered at the time of the first missed period. Oral contraceptive use
should be discontinued if pregnancy is confirmed.
Gallbladder Disease
Earlier studies have reported an increased lifetime
relative risk of gallbladder surgery in users of oral contraceptives and
estrogens.60,61 More recent studies, however, have shown that the
relative risk of developing gallbladder disease among oral contraceptive users
may be minimal. The recent findings of minimal risk may be related to the use
of oral contraceptive formulations containing lower hormonal doses of estrogens
and progestogens.
Carbohydrate And Lipid Metabolic Effects
Oral contraceptives have been shown to cause a decrease
in glucose tolerance in a significant percentage of users.17 This
effect has been shown to be directly related to estrogen dose.65 In
general, progestogens increase insulin secretion and create insulin resistance,
this effect varying with different progestational agents.17,66 In
the nondiabetic woman, oral contraceptives appear to have no effect on fasting
blood glucose.67 Because of these demonstrated effects, prediabetic
and diabetic women should be carefully monitored while taking oral
contraceptives.
A small proportion of women will have persistent
hypertriglyceridemia while on the pill. As discussed earlier, changes in serum triglycerides and lipoprotein levels have been
reported in oral contraceptive users.
Elevated Blood Pressure
Women with significant hypertension should not be started
on hormonal contraception.98 An increase in blood pressure has been
reported in women taking oral contraceptives68 and this increase is
more likely in older oral contraceptive users69 and with extended
duration of use.61 Data from the Royal College of General
Practitioners12 and subsequent randomized trials have shown that the
incidence of hypertension increases with increasing progestational activity and
concentrations of progestogens.
Women with a history of hypertension or
hypertension-related diseases, or renal disease70 should be
encouraged to use another method of contraception. If these women elect to use
oral contraceptives, they should be monitored closely and if a clinically
significant persistent elevation of blood pressure (BP) occurs ( ≥ 160 mm
Hg systolic or ≥ 100 mm Hg diastolic) and cannot be adequately
controlled, oral contraceptives should be discontinued. In general, women who
develop hypertension during hormonal contraceptive therapy should be switched
to a non-hormonal contraceptive. If other contraceptive methods are not
suitable, hormonal contraceptive therapy may continue combined with
antihypertensive therapy. Regular monitoring of BP throughout hormonal
contraceptive therapy is recommended.102 For most women, elevated
blood pressure will return to normal after stopping oral contraceptives,69
and there is no difference in the occurrence of hypertension among former and
never users.68,70,71
Headache
The onset or exacerbation of migraine or development of
headache with a new pattern which is recurrent, persistent or severe requires
discontinuation of oral contraceptives and evaluation of the cause.
Bleeding Irregularities
Breakthrough bleeding and spotting are sometimes encountered
in patients on oral contraceptives, especially during the first three months of
use. Nonhormonal causes should be considered and adequate diagnostic measures
taken to rule out malignancy or pregnancy in the event of breakthrough
bleeding, as in the case of any abnormal vaginal bleeding. If pathology has
been excluded, time or a change to another formulation may solve the problem.
In the event of amenorrhea, pregnancy should be ruled out.
Some women may encounter post-pill amenorrhea or
oligomenorrhea, especially when such a condition was pre-existent.
Ectopic Pregnancy
Ectopic as well as intrauterine pregnancy may occur in
contraceptive failures.
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