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THE BIRTH CONTROL PILL: HOW DOES IT WORK? IS IT SAFE?
by Paul Weckenbrock, R.Ph.
Copyright 1993. All Rights Reserved.
Reprinted Electronically via Permission of
John F. Kippley, President,
The Couple to Couple League
Controversy has surrounded "the Pill" ever since it was
first marketed in the United States in 1960. It has
been studied medically, sociologically and morally, and
yet much confusion still exists concerning these potent
artificial steroids. The billions of dollars at stake
in the marketing of the Pill and the power of the birth
control industry to lobby both lawmakers and the media
can easily divert the average person from the truth.
Research has been published, books have been written,
and common sense should make one cautious.
The following information is presented to raise
awareness about the Pill. Footnotes are marked with
asterisks; all footnotes appear at the end of this
document in a section titled REFERENCES.
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What is the Birth Control Pill?
The Birth Control Pill is any drug which uses
artificial hormones to keep a woman from getting
pregnant or from staying pregnant by interfering with
her normal fertility.
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Are all forms of the Pill the same?
No. There are several types of the Pill on the market,
but they basically break down into two groups:
combination pills and the progestin-only "minipill."
The combination type contain two artificial steroids
that mimic the effects of naturally occurring hormones,
estrogen and progesterone. Some pills work in a
"monophasic" way, keeping the dosage of hormones the
same throughout the pill cycle. Others work in a
biphasic or triphasic manner which alters the dosage of
artificial hormones two or three times respectively
through the cycle of pills, attempting to produce
fluctuations similar to what a fertile woman would
undergo naturally.
The progestin-only "minipill" uses only one artificial
hormone, progestin, which is a steroid that has a
progestational effect similar to natural progesterone.
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How does the Pill work?
The Pill is designed to interfere with several normal
functions of fertility in order to make a woman 1)
unable to conceive due to temporary sterility or sperm
immobility, and/or 2) unable to carry a pregnancy to
term(an early abortion). This process can be
accomplished in various ways.
1. Suppressing Ovulation: When a woman ovulates,
hormones released from the pituitary , a gland located
at the base of the brain, stimulate her ovaries to
ripen and release an egg. The combination pill usually
interrupts the release of these pituitary hormones
resulting in no egg being released from the ovary, thus
preventing pregnancy from occurring. With no egg
available for fertilization, the woman is chemically
sterile. The progestin-only pill, however, has a
weaker effect. It generally does not suppress
ovulation.*1*
2. Inhibiting Implantation: Another important aspect of
fertility is the process by which the lining of the
uterus is replenished and maintained. After an egg is
fertilized, it normally implants in this lining
(endometrium), drawing nourishment and sustenance. The
progestin component of the combination pill and the
progestin-only minipill cause the inner lining of the
uterus to become thin and shriveled, unable to support
implantation of the embryo(newly fertilized egg).*2*
3. Impeding Sperm Migration: Preceding ovulation, a
woman's cervix produces a watery mucus through which
sperm swim to meet the egg. The mucus also provides
nourishment to sustain the life of the sperm cells.
This mucus thickens under the influence of a progestin
and so impedes sperm migration.*3*
There are two other factors in a woman's fertility that
may be affected by the Pill.
4. Making changes in the Fallopian Tubes: Progestins
lower the efficiency with which the fallopian tubes
propel eggs from the ovaries toward the uterus. This
can cause the embryo not to reach the uterus in time to
implant successfully.*4*
5. Stopping a Pregnancy: After an ovary releases an
egg, the woman's cycle is controlled by a gland that is
formed from the now-empty egg sack, the corpus luteum;
this normally functions long enough to give an embryo
time to implant in the uterus and for the placenta to
begin to support the pregnancy.
However, hormones from the Pill can cause the corpus
luteum to function inadequately, allowing the lining of
the uterus to be shed before the embryo can
successfully implant.*5*
In summary, a woman's natural fertility requires
several systems and organs to coordinate smoothly. The
synthetic chemicals in any type of birth control Pill
interfere with this coordination, adversely affecting
her normal fertility and any "accidental" conceptions.
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How effective is the Pill?
In theory, the Pill reaches an effectiveness of over
99%, but in practice the rate is much lower. Between
1.9% and 18.1% of women will experience an unplanned
pregnancy in the first year of using the Pill.*6*
Surprise pregnancies with the Pill are due to a number
of factors. Interactions between the Pill and some
other medications interfere with the proper blood
levels of hormones necessary for their birth control
effect. These drug interactions may be significant with
the commonly used "low dose" Pill where slight
alterations in hormonal blood levels can result in more
frequent ovulations and hence unplanned pregnancies.
Another factor in Pill pregnancy rates is not following
directions, sometimes due to the lack of motivation,
especially in younger women (ages 15-24).
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Is ovulation always suppressed?
No. Ovulation occurs in 2% to 10% of cycles of women
taking the Pill.*7,8,9,10,11,12,13* If 60 million
women worldwide are on the low-dose Pill, there would
be 1.2 to 6 million ovulations per cycle. This is known
as breakthrough ovulation, and it is even more frequent
with the progestin-only Pill.*14,15*
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What happens when ovulation does occur?
When the Pill fails to prevent ovulation, the other
mechanisms come into play. Thickened cervical mucus may
make it more difficult for the sperm to reach the egg;
however, if the egg is fertilized, a new life is
created. The hormones slow the transfer of the new life
through the fallopian tube, and the embryo may become
too old to be viable when it does enter the uterus.
If the embryo is still viable when it reaches the
uterus, under-development of the uterine lining caused
by the Pill prevents implantation. The embryo dies and
the remains are passed along in the next bleeding
episode which, incidentally, is not a true menstruation
even though it is usually perceived as such.
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Does this mean the Pill can cause an early abortion?
Yes. Preventing the newly conceived life in its
embryonic stage from being transported to the uterus
and preventing implantation in the wall of the uterus
are the "abortifacient" properties of the Pill.
Why haven't I heard about this before?
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The Pill manufacturers and many in organized medicine
are mainly concerned about the Pill's medical side
effects and its effectiveness in preventing pregnancies
and are less concerned about how the drug achieves its
effectiveness.
Unfortunately, many "otherwise" pro-life physicians and
pharmacists find it hard to admit that these
abortifacient properties exist because they would have
to discontinue prescribing and dispensing the Pill if
they were to remain consistent in their respect for
life at all its stages of development.
Pro-abortion organizations and their lawyers readily
admit the early abortion potential of the Pill. In
February 1992, writing in opposition to a Louisiana law
banning abortion, Ruth Colker, a Tulane Law School
professor, wrote, "Because nearly all birth control
devices, except the diaphragm and condom, operate
between the time of conception...and implantation..,
the statute would appear to ban most
contraceptives."*16* In 1989, attorney Frank Sussman
argued before the U. S. Supreme Court that ". . . IUDs
[and] low dose birth control pills. . . act as
abortifacients."*17*
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Is It Safe? What are the common side effects of the
Pill?
There is a range of risks from serious or fatal to
minor and trivial. The following is a list of the most
common side effects experienced by women taking the
Pill. These effects are dose related and not every
woman will experience them, but the risks still
exist.*18,19* The synthetic estrogens of the
combination Pill cause many of these; the progestin
causes others and is the only risk factor in the
progestin-only Pill (and the progestin-only implant,
Norplant).
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Heart and blood abnormalities
Blood Clots can form, restricting or blocking the flow
of blood to critical organs and other body systems,
possibly causing permanent damage. For example, a blood
clot in the heart would cause a heart attack; in the
brain it would cause a stroke or brain hemorrhage; a
clot which moved from elsewhere in the body and lodged
in the lung would cause a pulmonary embolism; in the
kidneys a clot would cause a renal artery thrombosis
and kidney damage; in the retinal arteries it would
cause temporary or permanent blindness.
Studies continue to indicate approximately a 2-fold
increased risk of fatal heart attacks among users of
the current low-dose pill when compared to non-
users.*20* This risk is lower than the risk experienced
with the older high dosage pill, but it continues to be
significant. Similarly, the risk of a fatal brain
hemorrhage is increased 1.4 times when comparing users
to non-users. Among women who smoke, there is a 12-fold
increase in fatal heart attacks and a 3.1-fold increase
in fatal brain hemorrhage.*21*
High Blood Pressure and alterations in the blood
clotting mechanisms may be seen in women on the
Pill.*22* This may contribute to a 3-11 times
increased risk of developing blood clots in Pill users
compared to non-users. The risk is especially great for
women who smoke and/or are over 35 years old.*23*
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Cancer
Breast cancer has been repeatedly associated with using
the Pill.*24,25,26,27,28,29,30,31*
Breast cancer has been increasing at an alarming rate
in recent years, especially among young women. "Breast
cancer will kill more than 44,000 American women this
year alone," a 1991 report noted,*32* predicting
175,000 more new cases, "especially among young women."
Why is there such an increase of breast cancer among
younger women? Note first that women rarely develop
breast cancer shortly after they start taking
artificial hormones. It is generally not until ten or
more years after usage was initiated that women develop
breast cancer. Then note that in the United States,
since the mid-1970s, it has been common for the Pill to
be prescribed for girls in their teen years. Common
sense connects the link between giving the Pill to
young girls in the 1970s and the later increase in
breast cancer 15 to 20 years later among women in their
late twenties and thirties. This conclusion was
demonstrated in a study which found that Swedish women
who took the Pill in the 1960s incurred a five times
greater increase in breast cancer when compared to non-
users.*33*
The increased risk of breast cancer is seen in younger,
nulliparous women (never having borne children), and in
long duration groups (greater than five years) of Pill
users. Large tumors and a worse survival rate are
associated with the Pill's use at an early age.
Will the newer formulated low-dose pills decrease the
incidence of breast cancer? A consensus of
understanding has not been reached, and another 10 to
20 years of experience with women using this form of
the Pill must be gained before more definite
conclusions can be reached.
Breast tenderness, enlargement, lumps, and milk
secretions also may occur in women using the Pill.
Doctors are warned not to prescribe the Pill to women
who are "known or suspected" to have breast cancer.*34*
It is difficult to say what aggravating effect the
Pill's hormones would have over a truly random sample
of women taking the Pill.
Cervical Cancer and cervical dysplasia increase among
women who use the Pill.*35,36,37,38,39* How long the
Pill has been taken, how many sexual partners a woman
has had, at what age she began having intercourse,
whether she smokes, the hygiene of sexual partners and
the transmission of the human papillomavirus(HPV) are
also factors in cervical abnormalities. Because of
these several factors, the connection of the Pill and
cervical cancer may be clouded over. However, there is
no doubt that the promotion of the Pill has resulted in
early intercourse which may be the more direct cause of
cervical cancer.
Endometrial and Ovarian Cancer appear to have a lower
incidence in both women on the Pill and in those who
have been previous users of the Pill. Much of this data
comes from studies of women who were using the higher
dose estrogen/progestin Pill. Currently the low dose
monophasic and triphasic pills (less than 50mcg of
estrogen) are the only birth control pills available on
the U.S. market. It is not known if a similar
protective effect will be experienced with the
currently used Pill. More time is needed to study this
issue, and the slight protective effect is hardly a
reason to take the Pill at the risk of so many other
side effects.
It should also be noted that these forms of cancer are
rare and primarily occur among postmenopausal women in
their fifties and sixties. Second, these cancers tend
to occur in those women who had long cycles (i.e., with
a prolonged estrogen-dominant phase) or those who have
a family history of these types of cancer. Third,
extended breastfeeding amenorrhea offers the same type
of protection against these cancers since the menstrual
cycle would be suppressed and therefore the exposure to
estrogen suppressed.
Liver Tumors in younger women (15 to 40 years) have
increased as the use of oral contraceptives has
increased. Almost unheard of in this age group before
the use of synthetic hormones became commonplace, liver
tumors usually do not occur until the sixth decade of a
woman's life.
A study by the American College of Surgeons' Commission
on Cancer found "a large peak in the 26-to-30-year age
group which corresponds with the increased use of oral
contraceptives in this age group."*40* Liver cancer in
women on the Pill is typically associated with those
over 30 who have used it more than four years, but
cases of liver cancer in younger women have been
cited.*41,42,43,44*
Other Cancers: Skin cancer (melanoma) has also been
found to increase among women on the Pill. Naturally
occurring estrogen is involved with maintaining healthy
skin tissue. It is reasonable to suspect that exposure
to the more potent synthetic estrogen in the Pill
increases the risk of this type of cancer.*45,46,47*
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Cycle irregularities
Women who take the Pill have been reported to
experience bleeding or spotting in mid-cycle, changes
in menstrual flow, and even loss of menstruation, which
can lead them to wonder if they are pregnant. For some,
painful menstruation (dysmenorrhea) has been reported
to worsen, even though many women take these hormones
in an attempt to relieve the problem.*48*
Although some women are given the Pill for irregular
cycles, it does nothing to improve the underlying
problem causing the irregularity. Often the
irregularity returns when the Pill is discontinued,
sometimes more severely.
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Are there other side effects?
Yes. Some side effects are minor while some may be more
severe and call for discontinuing the drug.*49,50,51*
The following adverse effects have been experienced by
women on the Pill:
Headaches, migraines, mental depression (even to the
point of suicide and/or suicidal tendencies), a
decrease or loss of sexual drive, abdominal cramps,
bloating, weight gain or loss, and water retention;
nausea and vomiting(in about 10% of users); symptoms of
PMS, vaginitis and vaginal infections, changes in
vision (temporary or permanent blindness, and an
intolerance to contact lenses); gall bladder disease
and either temporary or permanent infertility, when
discontinuing the Pill, in users with previous
menstrual irregularities or who began the drug before
full maturity. Several of the symptoms, such as
migraine headaches, contraindicate the use of the Pill
because of life endangering complications.
Consult the Physicians' Desk Reference at your public
library or consult your pharmacist for a more complete
list of the Pill's harmful effects.
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Is the Pill safer than pregnancy?
No. The health risks of the Pill outweigh by far the
risks of pregnancy and childbirth to a woman's
health,*52* and any claim to the contrary is based on
erroneous comparisons between healthy women on the Pill
and women who do not receive normal care during
pregnancy.
A precondition for obtaining the Pill is routine
medical care and checkups. For example: if such a woman
on the Pill is diagnosed as "precancerous," or if some
other side effect is exhibited, she has the advantage
of early detection. However, many pregnant women do not
receive routine medical care. A clearer picture of the
safety of the Pill compared to the safety of pregnancy
would be made if healthy women receiving routine
medical care during pregnancy and delivery were
compared with women receiving routine medical care
while taking the Pill.
The mortality statistics of childbirth have
continuously declined since the early part of this
century, mostly due to better maternal healthcare.*53*
Most of the high risk pregnancies and deliveries occur
to women who have not sought proper medical
attention.*54* This is most evident in the Third World
where adequate health care is sparse.
Mortality statistics of pregnancy and delivery, usually
called maternal mortality, include the mortality rates
due to abortion. Abortion is clearly used as birth
control, preventing the birth of the child; therefore
it must be included with the mortality statistics of
birth control methods. In one study, 25% to 50% of the
reported maternal mortality was a result of deaths from
abortion.*55*
Fifty percent of woman taking the Pill discontinue it
within the first year because of side effects, the
development of benign breast disease, or some
abnormality of the sexual organs. Studies of Pill usage
do not include these women, and the result is an
unbalanced picture of only the healthiest of women who
tolerate the Pill.*56* This is compared with the
general population of women who are pregnant.
The fact is that there are 13.8 million women in the
U.S. and 60 million women worldwide who use the Pill
(conservative numbers).*57* And there are 7.9 Pill-
related deaths per 100,000 women ages 15-44.*58*
Therefore, one can calculate that there are over 1090
deaths each year in the U.S. alone simply due to the
Pill.
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But I've heard there are no side effects with the Pill
I use.
All drugs, including all brands of the birth control
pill, have potential side effects. There is no telling
in advance how any particular woman will react to the
Pill, but there is a good chance of some type of
reaction. It is possible that a woman will be unaware
that there is any connection between the reaction and
the Pill especially if it takes years to manifest
itself.
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Aren't there any therapeutic benefits from the Pill?
The only "indication," or use for the Pill that is
approved by the Food and Drug Administration is "the
prevention of pregnancy in women . . . as a method of
contraception."*59* Some unapproved uses, considered
experimental, include its use as a "morning after" pill
(causing an early abortion), and for relief from the
symptoms of mild endometriosis.*60*
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I'm breastfeeding my baby; can I use the Pill?
No. Artificial hormones pass from breast milk to the
baby; the Pill also decreases both the quantity and
protein content of the milk produced.*61*
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What is my alternative to using the Pill?
Natural Family Planning (NFP) is safe, healthy and
effective and it's also inexpensive. A woman observes
and records changes in her basal body temperature, the
normal flow of cervical mucus, and if she wishes, the
physical changes in the cervix itself. She then
crosschecks these signs of fertility to follow, day by
day, the natural course of her fertility cycle. No
drugs, no devices, no surgical procedures, no threat of
death, no side effects, no chemical abortions!
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Does NFP really work?
Yes. Married couples can achieve a 99% effectiveness
if they learn the method, correctly interpret the
fertility signs, and follow the rules.*62* One positive
side benefit for couples who are committed to making
this method work is the potential for a healthier
marriage -- psychologically, physically and
spiritually.*63,64*
-- Paul Weckenbrock, R.Ph.
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How can I find out more about Natural Family Planning?
Write the national office of The Couple to Couple
League, P. O. Box 111184, Cincinnati, OH 45211, USA; 1-
513-661-7612.
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Fertil Steril 48 (3), 409-413.
10. Edgren RA, Sturtevant FM (Aug 1976). Potencies of
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19. Ortho-Novum (1993). Physicians' Desk Reference,
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22. Stampfer MJ, Willett WC, Colditz GA, Speizer FE,
Hennekens CH (1990). Past use of oral contraceptives
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(1989). Breast cancer before age 45 and oral
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(1983). Breast cancer in young women and use of oral
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(May 1 1991). Beating breast cancer. New York: CBS.
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(1991). Early oral contraceptive use and premenopausal
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(1990). The pill: Combined oral contraceptives.
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melanoma in relation to exogenous hormones and
reproductive factors. J Natl Cancer Inst 70, 827.
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42, 531-535.
56. Grant E (1985). The bitter pill. London: Elm Tree
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57. Hatcher RA (1990). 228.
58. Harlap S (1991). 98-99.
59. Demulen (1992). Physicians' Desk Reference, 2253.
60. Oral Contraceptives (Nov 1989 insert). Facts and
Comparisons. 107c.
61. Oral Contraceptives (Nov 1989 insert). Facts and
Comparisons. 107g.
62. Wade ME, McCarthy P, Braunstein GD and 5 others
(1981). A randomized prospective study of the use-
effectiveness of two methods of natural family
planning. Am J Obstet Gynecol 141 (4) 368-376.
63. Kippley, J Kippley, S (1991). The Art of Natural
Family Planning. (3rd ed, 5th print) Cincinnati: Couple
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64. Tortorici, J (1979). Conception regulation, self-
esteem, marital satisfaction among Catholic couples:
Michigan State University study. Int Rev NFP III(3)
191-205.
c 1993 The Couple to Couple League International, Inc,
P.O. Box 111184, Cincinnati, OH 45211-1184, USA, 1-513-
661-7612. CompuServe Address: 73311,256. Web home
page: http://www.dris.com/~megamall/cathlc/ccl
The information contained in this document is for
private use and may not be reproduced, published,
broadcast or otherwise distributed without the prior
written permission of the Couple to Couple League.
This information is from a brochure titled "The Pill:
How does it Work? Is it Safe?" The brochure and
related material may be ordered from Couple to Couple
League direct.
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