Conception and Contraception

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Methods of Birth Control
Conception and Contraception
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Conception refers to the fertilization of an ovum
by a sperm. It must involve:
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A viable egg
A viable sperm
Access to the egg by the sperm
Contraception refers to methods of preventing
conception. 2 methods of effectiveness include:
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Perfect failure rate: risk of pregnancy during the first
year of use if the method is used w/o error
Typical failure rate: risk of pregnancy during the first
year of use w/ normal number of errors
Reversible Methods of Birth Control
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Intrauterine Devices (IUDs)
Hormonal methods
Barrier methods
Fertility awareness and abstinence
Intrauterine Devices (IUDs)
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Copper T IUD—An IUD is a small device that is shaped in the form of
a “T.” Your doctor places it inside the uterus to prevent pregnancy. It
can stay in your uterus for up to 10 years. This IUD is more than 99%
effective at preventing pregnancy.
Hormonal Methods
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Hormonal methods introduce synthetic hormones
into the women’s system that prevent ovulation,
thicken cervical mucus or prevent a fertilized egg
from implanting.
Oral contraceptives combine synthetic estrogen
and progesterone to prevent release of an ova
from the ovary, preventing pregnancy.
Progestin-only pills contain small doses of
progesterone and are used when suffer from sideeffects related to estrogen or are nursing a baby –
slightly less effective than combination pills.
Hormonal methods

Oral contraceptives—Also called “the pill,” it contains the
hormones estrogen and progestin. It is prescribed by a
doctor. A pill is taken at the same time each day. If you are
older than 35 years and smoke, have a history of blood clots
or breast cancer, your doctor may advise you not to take the
pill. The pill is 92–99% effective at preventing pregnancy.
Early Warning Signs of Medical
Complications for Pill Users
Figure 7.6
Hormonal methods

Patch—This skin patch is worn on the lower abdomen,
buttocks, or upper body (but not on the breasts). This
method is prescribed by a doctor. It releases hormones
progestin and estrogen into the bloodstream. You put on a
new patch once a week for three weeks. During the fourth
week, you do not wear a patch, so you can have a menstrual
period. The patch is 92–99% effective at preventing
pregnancy, but it appears to be less effective in women who
weigh more than 198 pounds.
Hormonal methods
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Hormonal vaginal contraceptive ring— The NuvaRing
releases the hormones progestin and estrogen. You place
the ring inside your vagina. You wear the ring for three
weeks, take it out for the week you have your period, and
then put in a new ring. It is 92–99% effective at preventing
pregnancy.
Hormonal methods
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Injection or "shot"—
Women get shots of
the hormone progestin
in the buttocks or arm
every three months
from their doctor. It is
97–99% effective at
preventing pregnancy.
Hormonal methods

Implant—The implant is a single, thin rod that
is inserted under the skin of a women’s upper
arm. The rod contains a progestin that is
released into the body over 3 years. It is 99
percent effective at preventing pregnancy.
Hormonal methods
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Emergency contraception—Emergency contraception
is NOT a regular method of birth control. Emergency
contraception can be used after no birth control was
used during sex, or if the birth control method failed,
such as if a condom broke.
One type of emergency contraception requires you to
take two doses of hormonal pills 12 hours apart or take
both pills at one time. (This is now over the counter for
those who are 18 years old and older. You have to take
the pills starting within three days (72 hours) after
having unprotected sex. They are sometimes referred
to as “morning after” pills, even though they can be
used up to three days later. The pills are at least 75%
effective at preventing pregnancy. Plan B is available
over-the-counter for women aged 18 years and older.
Plan B is available by prescription for women aged 17
years and younger. (Plan B is the brand name of one
product approved by the Food and Drug
Administration for use as emergency contraception.)
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Barrier methods: use of a physical or chemical block to
prevent the egg and sperm from joining
Male condom – latex sheath designed to fit over erect
penis catching ejaculate.
Foams, suppositories, jellies and creams contain chemical
spermicides which kill sperms & some STIs
Female condom is soft loose fitting polyurethane sheath
that covers the external genitalia.
Diaphragm w/ spermicide provides chemical and physical
barrier to sperm
Cervical cap – small latex cap that fits snugly over the
cervix to keep sperm out of uterus
Barrier Methods
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Male condom—Worn by the man, a male condom keeps
sperm from getting into a woman’s body. Latex condoms,
the most common type, help prevent pregnancy and HIV
and other STDs as do the newer synthetic condoms.
“Natural” or “lambskin” condoms also help prevent
pregnancy, but may not provide protection against STDs,
including HIV. Male condoms are 85–98% effective at
preventing pregnancy. Condoms can only be used once,
and are most effective when used consistently and
correctly. You can buy condoms, KY jelly, or water-based
lubricants at a drug store. Do not use oil-based lubricants
such as massage oils, baby oil, lotions, or petroleum jelly
with latex condoms. They will weaken the condom, causing
it to tear or break.
Barrier methods
Male Condoms
A male condom is a thin sheath
made of latex or other materials
Latex condoms
protect against pregnancy & STDs
Male Condoms
1700
1800
1993
Male Condoms
Available in various shapes,
colours, flavours, textures and sizes
Latex and polyurethane condoms also provide limited protection against
HPV that can cause genital warts
HSV that can cause genital herpes
Hepatitis-B virus
Male Condoms
How do they work?
The man puts the condom on his erect penis
The condom holds the semen
After sex, the man carefully takes off the
condom so that it does not leak.
Each condom can be used only once.
Male Condoms
Male condom instructions
Leave about one-half inch of empty space at the tip
After intercourse, hold onto the condom at the base of the penis as
you withdraw from the vagina
Lubricating the condom – contraceptive cream or jelly
For latex condom, do not use oil-based lubricants (such as petroleum
jelly or vegetable oils)
tear
Male Condoms
Benefits
No medical side-effects
inexpensive, easily accessed
Protecting against STDs ( Latex )
Condoms can help men maintain an erection for a longer period
Lower risk for cervical dysplasia and cancer
Condoms also prevent sperm allergy which some women suffer
Male Condoms
Can interrupt sexual activity
Some individuals argue that condoms reduce
sensitivity and pleasure during intercourse
May sometimes tear or leak
Can cause an allergic reaction
Female Condom
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Worn by the woman, the female condom
helps keeps sperm from getting into her
body. It is packaged with a lubricant and is
available at drug stores. It can be inserted
up to eight hours before sexual intercourse.
Female condoms are 79–95% effective at
preventing pregnancy when used
consistently and correctly, and may also help
prevent STDs.
Has two flexible rings
The inner ring at the closed end of the condom eases
insertion into the vagina, covering the cervix and holding
the condom in place
The outer ring , The larger, open ring stays outside the
vagina, covering part of the perineum and labia during
intercourse.
Spermicides
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These products work by killing sperm and come in
several forms—foam, gel, cream, film, suppository,
or tablet. They are placed in the vagina no more
than one hour before intercourse. You leave them
in place at least six to eight hours after intercourse.
You can use a spermicide in addition to a male
condom, diaphragm, or cervical cap. Spermicides
alone are about 71–82% effective at preventing
pregnancy. They can be purchased in drug stores.
barrier method
Spermicides
Spermicides are chemical
compounds act to inactivate
sperms in the vagina before it can
move into the upper genital tract
Spermicides , CHEMICAL NATURE
TWO BASIC COMPONENTS :
1-ACTIVE SPERMICIDAL AGENTS :
Surface acting (surfactants)
Nonoxynol-9
Octoxynol-9
Menfegol
Recently with antiviral activity :
CHLORHEXIDINE,CHOLIC ACID & GRAMICIDINE.
2- THE BASE ( CARRIER ) AGENT
foams, jellies, creams, foaming tablets, melting
suppositories ,aerosols soluble films
or vaginal suppositories.
Spermicides
How do I use spermicides?
*Every time of sexual intercourse.
*Insert the recommended dose deep into vagina to
cover the cervix well just before sexual intercourse
*Insert tablets or suppositories or films 10 minutes
( 5-30 min) before sexual intercourse
Spermicides
*Use a second dose of spermicides
If more than one hour passes before you have
sexual intercourse
*An additional application of the spermicides is
needed for each additional act of intercourse
*Douching should not be allowed for at least 6
hours after intercourse
Spermicides
Characteristics of spermicides?
Does not require a prescription
May be discontinued at any time
Safe
May cause irritation in the vagina or on the penis
Can cause an allergic reaction
May interrupt sexual activity
Not recommended for preventing STIs
Diaphragm or cervical cap
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Each of these barrier methods are placed
inside the vagina to cover the cervix to block
sperm. The diaphragm is shaped like a
shallow cup. The cervical cap is a thimbleshaped cup. Before sexual intercourse, you
insert them with spermicide to block or kill
sperm. The diaphragm is 84–94% effective
at preventing pregnancy. Visit your doctor
for a proper fitting because diaphragms and
cervical caps come in different sizes.
The Diaphragm
TYPES
Coil Spring
Arching Spring
Flat Spring
barrier methods
Cervical Cap
A cervical cap is a soft, deep rubber cup
(like a thimble) with a firm, round rim that
fits snugly over the cervix.
Cervical Cap
Different sizes
With Spermicide
TYPES
Fertility awareness and abstinence
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Continuous abstinence—This method means not
having vaginal intercourse at any time. It is the
only 100% effective way to prevent pregnancy.
Natural family planning or fertility awareness—
Understanding your monthly fertility pattern can
help you plan to get pregnant or avoid getting
pregnant. Your fertility pattern is the number of
days in the month when you are fertile (able to get
pregnant), days when you are infertile, and days
when fertility is unlikely, but possible. If you have
a regular menstrual cycle, you have about nine or
more fertile days each month. If you do not want
to get pregnant, you do not have sex on the days
you are fertile, or you use a form of birth control
on those days. These methods are 75–99% effective
at preventing pregnancy.
Withdrawal
Withdrawal is a method in which
the man takes his penis out of
the woman's vagina just before
he ejaculates
Permanent Methods of Birth Control
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These methods are meant for people who want a permanent method of birth
control. In other words, they never want to have a child, or they do not want
more children. The methods listed here are more than 99% effective at
preventing pregnancy.
Female Sterilization—Tubal ligation or “tying tubes.”— A woman can have her
fallopian tubes tied (or closed) so that sperm and eggs cannot meet for fertilization.
The procedure can be done in a hospital or in an outpatient surgical center. You can go
home the same day of the surgery and resume your normal activities within a few days.
This method is effective immediately.
Transcervical Sterilization— A thin tube is used to thread a tiny device into each
fallopian tube. It irritates the fallopian tubes and causes scar tissue to grow and
permanently plug the tubes. It can take about three months for the scar tissue to grow,
so use another form of birth control during this time. Return to your doctor for a test
to see if scar tissue has fully blocked your fallopian tubes.
Male Sterilization–Vasectomy—This operation is done to keep a man’s sperm from
going to his penis, so his ejaculate never has any sperm in it that can fertilize an egg.
This operation is simpler than tying a woman’s tubes. The procedure is done at an
outpatient surgical center. The man can go home the same day. Recovery time is less
than one week. After the operation, a man visits his doctor for tests to count his sperm
and to make sure the sperm count has dropped to zero; this takes about 12 weeks.
Another form of birth control should be used until the man’s sperm count has
dropped to zero.
Surgical Methods
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Sterilization
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Female
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Tubal ligation is a method where surgery ties or cuts and
cauterizes the uterine tubes. This blocks the sperm’s access to
released eggs.
Hysterectomy is the surgical removal of the uterus. It’s usually
done only when there is disease or damage to the uterus.
Male
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Vasectomy is a procedure where both ductus deferens are
surgically cut and tied shut.
Sterilization
Figure 7.7
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