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Protecting
Against Unintended Pregnancy:
A Guide to Contraceptive Choices
by Tamar Nordenberg
I
am 20 and have never gone to see a doctor about birth control. My boyfriend
and I have been going together for a couple of years and have been using
condoms. So far, everything is fine. Are condoms alone safe enough,
or is something else safe besides the Pill?
--Letter to the Kinsey Institute for Research in Sex, Gender, and Reproduction
This young woman is not alone
in her uncertainty about contraceptive options. A 1995 report by the
National Academy of Sciences' Institute of Medicine, The Best Intentions:
Unintended Pregnancy and the Well-being of Children and Families, attributed
the high rate of unintended pregnancies in the United States, in part,
to Americans' lack of knowledge about contraception. About 6 of every
10 pregnancies in the United States are unplanned, according to the
report.
Being informed about the pros
and cons of various contraceptives is important not only for preventing
unintended pregnancies but also for reducing the risk of illness or
death from sexually transmitted diseases (STDs), including AIDS. (See
"Preventing
HIV and Other STDs.")

The Food and Drug Administration
has approved a number of birth control methods, ranging from over-the-counter
male and female condoms and vaginal spermicides to doctor-prescribed
birth control pills, diaphragms, intrauterine devices (IUDs), injectable
hormones, and hormonal implants. Other contraceptive options include
fertility awareness and voluntary surgical sterilization.
"On the whole, the contraceptive
choices that Americans have are very safe and effective," says
Dennis Barbour, former president of the Association of Reproductive
Health Professionals, "but a method that is very good for one woman
may be lousy for another."
The choice of birth control
depends on factors such as a person's health, frequency of sexual activity,
number of partners, and desire to have children in the future. Effectiveness
rates, based on statistical estimates, are another key consideration.
(See "Birth
Control Guide.") FDA has developed a consumer-friendly
table of pregnancy rates which the agency encourages all contraceptive
marketers to add to their products' labeling. Single copies of the table
may be ordered from FDA, HFZ-210, 1350 Piccard Drive, Rockville, MD
20850.
Barrier Methods
Male Condom.
The male condom is a sheath
placed over the erect penis before penetration, preventing pregnancy
by blocking the passage of sperm.
A condom can be used only
once. Some have a chemical added to kill sperm. The addition of this
spermicide, usually nonoxynol-9 in the United States, has not been scientifically
shown to provide additional contraceptive protection over the condom
alone. Because it acts as a mechanical barrier, a condom prevents direct
contact with semen, infectious genital secretions, and genital lesions
and discharges.
Most condoms are made from
latex rubber, while a small percentage are made from lamb intestines
(sometimes called "lambskin" condoms). Condoms made from a
type of plastic called polyurethane have been marketed in the United
States since 1994.
Except for abstinence, latex
condoms are the most effective method for reducing the risk of infection
from the viruses that cause AIDS, other HIV-related illnesses, and other
STDs. For people who are sensitive to latex, polyurethane condoms are
a good alternative.
Some condoms are prelubricated.
These lubricants do not increase birth control or STD protection. Non-oil-based
lubricants, such as water or K-Y jelly, can be used with latex or lambskin
condoms, but oil-based lubricants, such as petroleum jelly (Vaseline),
lotions, or massage or baby oil, should not be used because they can
weaken the condom and cause it to break.
Female condom
The Reality Female Condom,
approved by FDA in April 1993, consists of a lubricated polyurethane
sheath shaped similarly to the male condom. The closed end, which has
a flexible ring, is inserted into the vagina, while the open end remains
outside, partially covering the labia.
The female condom, like the
male condom, is available without a prescription and is intended for
one-time use. It should not be used together with a male condom because
they may slip out of place.
Diaphragm.
Available by prescription
only and sized by a health professional to achieve a proper fit, the
diaphragm is a dome-shaped rubber disk with a flexible rim that works
in two ways to prevent pregnancy. It covers the cervix so sperm can't
reach the uterus, while a spermicide cream or jelly applied to the diaphragm
before insertion kills sperm.
The diaphragm protects for
six hours after it is inserted. For intercourse after the six-hour period,
or for repeated intercourse within this period, fresh spermicide should
be placed in the vagina with the diaphragm still in place. The diaphragm
should be left in place for at least six hours after the last intercourse
but not for longer than a total of 24 hours because of the risk of toxic
shock syndrome (TSS), a rare but potentially fatal infection. Symptoms
of TSS include sudden fever, stomach upset, sunburn-like rash, and a
drop in blood pressure.
Cervical cap.
The cervical cap is a soft
rubber cup with a round rim, sized by a health professional to fit snugly
around the cervix. It is available by prescription only and, like the
diaphragm, is used with spermicide cream or jelly.
It protects for 48 hours and
for multiple acts of intercourse within this time. Wearing it for more
than 48 hours is not recommended because of the risk, though low, of
TSS. Also, with prolonged use of two or more days, the cap may cause
an unpleasant vaginal odor or discharge in some women.
Sponge.
The sponge, a disk-shaped
polyurethane device containing the spermicide nonoxynol-9, is not currently
marketed but may be sold again in the future. Inserted into the vagina
to cover the cervix, the sponge is attached to a woven polyester loop
for easier removal.
The sponge protects for up
to 24 hours and for multiple acts of intercourse within this time. It
should be left in place for at least six hours after intercourse but
should be removed no more than 30 hours after insertion because of the
risk, though low, of TSS.
Vaginal Spermicides Alone
Vaginal spermicides are available
in foam, cream, jelly, film, suppository, or tablet forms. All types
contain a sperm-killing chemical.
Studies have not produced
definitive data on how well spermicides alone prevent pregnancy, but
according to the authors of Contraceptive Technology, a leading resource
for contraceptive information, the failure rate for typical users may
be 26 percent per year.
Package instructions must
be carefully followed because some spermicide products require the couple
to wait 10 minutes or more after inserting the spermicide before having
sex. One dose of spermicide is usually effective for one hour. For repeated
intercourse, additional spermicide must be applied. And after intercourse,
the spermicide has to remain in place for at least six to eight hours
to ensure that all sperm are killed. The woman should not douche or
rinse the vagina during this time.
Hormonal Methods
Combined oral
contraceptives.
Typically called "the
pill," combined oral contraceptives have been on the market for
about 40 years and are the most popular form of reversible birth control
in the United States. This form of birth control suppresses ovulation
(the monthly release of an egg from the ovaries) by the combined actions
of the hormones estrogen and progestin.
If a woman remembers to take
the pill every day at the same time of day as directed, she has an extremely
low chance of becoming pregnant. But the pill's effectiveness may be
reduced if the woman is taking some medications, such as certain antibiotics.
Besides preventing pregnancy,
the pill offers additional benefits. As stated in the labeling, the
pill can make periods more regular and lighter. It also has a protective
effect against pelvic inflammatory disease, an infection of the fallopian
tubes or uterus that is a major cause of infertility in women, and against
ovarian and endometrial cancers.
The decision whether to take
the pill should be made in consultation with a health professional.
Birth control pills are safe for most women--safer even than delivering
a baby--but they carry some risks.
Current low-dose pills have
fewer risks associated with them than earlier versions. But women over
age 35 who smoke and women with certain medical conditions, such as
a history of blood clots or breast or endometrial cancer, may be advised
against taking the pill. The pill may contribute to cardiovascular disease,
including high blood pressure, blood clots, and blockage of the arteries.
One of the biggest questions has been whether the pill
increases the risk of breast cancer in past and current pill users.
An international study published in the September 1996 journal Contraception
concluded that women's risk of breast cancer 10 years after going off
birth control pills was no higher than that of women who had never used
the pill. During pill use and for the first 10 years after stopping
the pill, women's risk of breast cancer was only slightly higher in
pill users than non-pill users. Women who have or have had breast cancer
should not use the pill because the estrogen in the pill may cause their
medical condition to worsen.
Side effects of the pill,
which often subside after a few months' use, include nausea, headache,
breast tenderness, weight gain, irregular bleeding, and depression.
Minipills.
Although taken daily like
combined oral contraceptives, minipills contain only the hormone progestin
and no estrogen. They work by reducing and thickening cervical mucus
to prevent sperm from reaching the egg. They also keep the uterine lining
from thickening, which prevents a fertilized egg from implanting in
the uterus. These pills are slightly less effective than combined oral
contraceptives.
Minipills, like combined oral
contraceptives, can decrease menstrual bleeding and cramps, as well
as the risk of endometrial and ovarian cancer and pelvic inflammatory
disease. Because they contain no estrogen, minipills don't present the
risk of blood clots associated with estrogen in combined pills. They
are a good option for new mothers who are breastfeeding because combined
oral contraceptives may decrease the quantity and quality of breast
milk. They are also a good option for those who get severe headaches
or high blood pressure from estrogen-containing products.
Side effects of minipills
include menstrual cycle changes, weight gain, and breast tenderness.
Emergency Contraceptive
("Morning After Pill")
Two emergency contraceptive
pill products have been approved by FDA for use in preventing pregnancy
after intercourse when standard contraceptives have failed or when no
contraceptives were used at all. One product contains the hormones progestin
and estrogen; the other contains just progestin.
Available by prescription
only, both products are believed to work by delaying or inhibiting ovulation,
or by keeping a fertilized egg from implanting in the uterine wall.
These pills are not effective once the fertilized egg has implanted.
Emergency contraceptives are
about 75 percent effective, which means the number of women who would
be expected to become pregnant after unprotected sex drops from eight
without the "morning after pill" to two when it is used.
Side effects include nausea
and vomiting, both of which were reported less frequently in women taking
the progestin-only pills.
Injectable progestins.
Depo-Provera, approved by
FDA in 1992, is injected by a health professional into the buttocks
or arm muscle every three months. Depo-Provera prevents pregnancy in
three ways: It inhibits ovulation, changes the cervical mucus to help
prevent sperm from reaching the egg, and changes the uterine lining
to prevent the fertilized egg from implanting in the uterus. The progestin
injection is extremely effective in preventing pregnancy, in large part
because it requires little effort for the woman to comply: She simply
has to get an injection by a doctor once every three months.
The benefits are similar to
those of the minipill and another progestin-only contraceptive, Norplant.
Side effects are also similar and can include irregular or missed periods
(which is not harmful and does not mean that the method isn't working),
weight gain, and breast tenderness.
Implantable progestins.
Norplant, approved by FDA
in 1990, and the newer Norplant 2, approved in 1996, are the third type
of progestin-only contraceptive. Made up of matchstick-sized rubber
rods, this contraceptive is surgically implanted under the skin of the
upper arm, where it steadily releases the contraceptive steroid levonorgestrel.
The six-rod Norplant provides
protection for up to five years (or until it is removed), while the
two-rod Norplant 2 protects for up to three years. Norplant failures
are rare, but are higher with increased body weight.
Some women may experience
inflammation or infection at the site of the implant. Other side effects
include menstrual cycle changes, weight gain, and breast tenderness.
Intrauterine Devices
An IUD is a mechanical device
inserted into the uterus by a health-care professional. Two types of
IUDs are available in the United States: the Paragard CopperT 380A and
the Progestasert Progesterone T. The Paragard IUD can remain in place
for 10 years, while the Progestasert IUD must be replaced every year.
It's not entirely clear how
IUDs prevent pregnancy. They seem to prevent sperm and eggs from meeting
by either immobilizing the sperm on their way to the fallopian tubes
or changing the uterine lining so the fertilized egg cannot implant
in it.
IUDs have one of the lowest
failure rates of any contraceptive method. "In the population for
which the IUD is appropriate--for those in a mutually monogamous, stable
relationship who aren't at a high risk of infection--the IUD is a very
safe and very effective method of contraception," says Lisa Rarick,
M.D., director of FDA's division of reproductive and urologic drug products.
The IUD's image suffered when
the Dalkon Shield IUD was taken off the market in 1975. This IUD was
associated with a high incidence of pelvic infections and infertility,
and some deaths. Today, serious complications from IUDs are rare. Side
effects can include pelvic inflammatory disease (an infection of a woman's
reproductive organs), ectopic pregnancy (in which a fertilized egg implants
in the fallopian tube instead of the uterus), perforation of the uterus,
heavier-than-normal bleeding, and cramps. Complications occur most often
during and immediately after insertion.
Traditional Methods
Fertility awareness.
Also known as natural family
planning or periodic abstinence, fertility awareness entails not having
sexual intercourse on the days of a woman's menstrual cycle when she
is more likely to become pregnant or using a barrier method of birth
control on those days.
Because a sperm may live in
the female's reproductive tract for up to seven days and the egg may
remain fertile for about 24 hours, a woman could get pregnant from intercourse
that occurred from seven days before ovulation to 24 hours or more after.
Methods to approximate when a woman is fertile are usually based on
the menstrual cycle, changes in cervical mucus, or changes in body temperature.
"Natural family planning
can work," Rarick says, "but it takes an extremely motivated
couple to use the method effectively."
Withdrawal.
In this method, also called
coitus interruptus, the man withdraws his penis from the vagina before
ejaculation. Fertilization is prevented if the sperm don't enter the
vagina.
Effectiveness depends on the
male's ability to withdraw before ejaculation. Also, withdrawal doesn't
provide protection from STDs, including HIV. Infectious diseases can
be transmitted by direct contact with surface lesions and by pre-ejaculatory
fluid.
Surgical Sterilization
Surgical sterilization is
a contraceptive option intended for people who don't want children in
the future. It is considered permanent because reversal requires major
surgery that is often unsuccessful.
Female sterilization.
Female sterilization blocks
the fallopian tubes so the egg can't travel to the uterus. Sterilization
is done by various surgical techniques, usually under general anesthesia.
Complications from these operations
are rare and can include infection, ectopic pregnancy, hemorrhage, and
problems related to the use of general anesthesia.
Male sterilization.
This procedure, called a vasectomy,
involves sealing, tying or cutting a man's vas deferens, which otherwise
would carry the sperm from the testicle to the penis.
Vasectomy involves a quick
operation, usually under 30 minutes, with possible minor postsurgical
complications, such as bleeding or infection.
Research continues on effective
contraceptives that minimize side effects. One important research focus,
according to FDA's Rarick, is the development of birth control methods
that are both spermicidal and microbicidal to prevent not only pregnancy
but also transmission of HIV and other STDs.
Tamar Nordenberg
is a staff writer for FDA Consumer.
Publication
No. (FDA) 00-1277
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