2. Choosing a Birth Control Method
things to consider
• Effectiveness--statistics show two numbers:
– Failure rate: # of women per 100 who become pregnant
after 1 yr. when using a b.c. consistently & correctly
– Typical use failure rate--takes into account improper or
inconsistent use
• Factors that contribute to improper use include: lack of partner
involvement, forgetfulness, feeling guilty about sex, poor
communication w/partner, not wanting to appear “easy”
– About half of all unintended pregnancies occur among
women using contraceptives
• Cost
• Ease of use
• Side effects
3. Effectiveness of birth control methods
FDA, 1997
w/o spermicide
Also see
Table
10.1
p. 268
4. Using backup methods to increase
contraceptive effectiveness
• Backup methods: contraceptive methods used
simultaneously w/another method to support it
• Condoms, foam, diaphragm, can all be combined w/other
methods for extra protection
• When a backup method might be a good idea:
– If on the pill:
• During first cycle of the pill
• After forgetting 2 or more pills, or after several days of diarrhea or
vomiting when on the pill
• First month after switching pill type
• When taking medications that can reduce effectiveness of the pill
– During first 1-3 months after IUD insertion
– When first learning how to use a new method
– To increase overall effectiveness of contraception
5. “Outercourse”
• Noncoital forms of sexual intimacy
• Kissing, touching, mutual masturbation, oral sex, anal
sex
• Any type of sexual intimacy that avoids male
ejaculation near vaginal opening
• Can be primary or temporary means of preventing
pregnancy
• Can also be used when it’s not advisable to have
intercourse for other reasons, such as after childbirth
or abortion
• No undesirable contraceptive side effects
• Does not eliminate chances of spreading STDs,
especially if it involves oral or anal sex
…is to prevent
pregnancy, not to
protect against
STI’s
7. How hormonal
contraceptives
work
FSH & LH trigger
ovulation
Gonadotropin releasing
hormone (GnRH) triggers
release of gonadotropins
FSH & LH
Estrogen & progesterone in
hormonal contraceptives
inhibit LH, FSH, and GnRH
secretion, preventing ovulation
Progesterone also:
•thickens cervical mucus to prevent
Passage of sperm into the uterus
•changes uterine lining to inhibit implantation
8. Types of oral contraceptives
• Constant-dose combination pill
– Contains both estrogen and progestin
– Dose of each is constant throughout cycle
– Amount of estrogen in pills has decreased from approx. 175
micrograms in 1960 to avg. of 25 micrograms today
• Triphasic pill
– Levels of hormones (estrogen & progestin) fluctuate during cycle
• Seasonale
– Reduces the # of menstrual periods to 4 instead of 13 per year
– Has lower dose of estrogen and progestin
• Progestin-only pill
– Low dose of progestin and no estrogen
– For women who should not take estrogen (breastfeeding, high
b.p., at risk for blood clots, smoke)
9. How to use oral contraceptives
• Different types of OCs will differ in how to begin,
and other instructions--read instructions carefully &
talk w/health care practitioner
• Don’t skip pills, regardless of whether or not you
are having sex
• Take pill at the same time each day
– If you miss 1 pill: take missed pill as soon as you
remember, and then take next pill at the regular time
– If you miss >1 pill: consult health care practitioner for
advice; use a backup method for remainder of your cycle
10. Oral contraceptives
possible side effects & health issues
• Women who should not take OCs:
– history of blood clots, strokes, heart/circulation
problems, jaundice, breast or uterine cancer, liver
disease
• Women considered risky for taking OCs:
– Women who smoke, have migraines, depression, high
b.p., epilepsy, diabetes/prediabetes, asthma, varicose
veins
• Side effects of OCs can include:
– Weight gain, decreased sexual interest, headaches,
mood changes, nausea, bleeding between periods
– May clear up after 2-3 cycles on the pill
11. Oral contraceptives
possible side effects & health issues
• Rare but serious side effects of OCs--must be
reported to a health care practioner ASAP
10.3
12. Other hormonal methods
(contain both estrogen and progestin)
• Vaginal ring (Nuvaring)
– 2” ring inserted into the vagina during period
– Worn for 3 weeks, removed for 1 week, then
replaced with new ring
– Cost per year: $580
– Pros: no daily pill; spontaneity
– Cons: no STD protection, not effective for
women over 198 lbs.
• Transdermal patch (Ortho Evra)
– Patch is placed on buttock, abdomen, outer
upper arm, or upper torso
– Replaced weekly for 3 weeks, then a patch-
free week
– Cost per year: $420
– Pros: no daily pill; spontaneity
– Cons: no STD protection, skin irritation
13. Other hormonal methods (cont.)
• Injected Contraceptives
– Depo-Provera (prog.); Lunelle (prog.+est.)
– Injections: D-P every 12 weeks; Lunelle monthly
– Cost per year: $196 for D-P; $420 for Lunelle
– Pros: no daily pill; spontaneity
– Cons: no STD protection, weight gain,
bleeding, mood change, frequent clinic visits
– D-P: takes up to 10 months for a woman
to get pregnant after stopping injections
• Contraceptive Implants
– 1.5” rod is inserted under skin of upper arm
– Progestin-only
– Effective for up to 3 years
– Cost not yet known
– Pros: no daily pill; spontaneity
– Cons: no STD protection, weight gain,
bleeding, mood change, surgical procedure
14. Barrier & spermicide methods
• Include:
– Condoms (male & female)
– Spermicides (foam, sponge)
– Cervical barriers (diaphragm & cervical cap)
• Work by preventing sperm from reaching an
egg
• Only condoms provide protection against
STIs
15. Condoms (male)
• Sheath that fits over the erect penis
• The only temporary method of birth
control for men
• Only form of contraception that
effectively reduces STI transmission
• Made of thin latex, polyurethane, or natural membrane
– Natural membrane (from sheep intestines) condoms can permit passage
of viruses, incl. those that cause AIDS, herpes, hepatitis, HPV
• Many varieties
– Different features, shapes, textures, colors, flavors
– Some “extended pleasure” types have a desensitizing agent on the
inside to delay ejaculation
– Lubricated or nonlubricated
• Note: average shelf life of condoms is 5 years; don’t store latex
condoms in hot places (glove compartment, back pocket) b/c heat
can deteriorate the latex
16. How to use the (male) condom
• Pinch reservoir tip or twist tip of nonreservoir tip condom before
unrolling condom over the penis to leave room for ejaculate--
reduces chance of condom breaking
• Unroll condom over erect penis before any contact between the penis
and vulva occurs
– Common error: putting on a condom after vaginal penetration but
before ejaculation--increases risk of pregnancy & STI transmission
• Use a water-based lubricant to reduce risk of condom breaking (oil-
based lubricants deteriorate condom)
• Hold condom at the base of the penis before withdrawing from the
vagina to avoid spilling semen inside vagina
17. Female condom
• Consists of two flexible polyurethane rings and a
soft, loose-fitting polyurethane sheath
– One ring at closed end fits loosely against cervix; other
ring at open end encircles the labial area
• Can be inserted before sexual activity; don’t need to
remove it immediately following ejaculation
18. Costs, pros, & cons of condoms
• Costs
– Male condoms, about $0.75-$1 each
– Female condoms, about $3 each
• Advantages
– STI protection!
– Available w/o prescription or medical intervention
• Disadvantages
– Can reduce sensation
• Polyurethane transmits heat well, so some say that the female
condom has less reduction in sensation
– Interruption of sexual experience (though some couples find
sensual ways of incorporating condoms into foreplay)
– Note: female condom can be inserted several hours before intercourse
19. Vaginal spermicides
• Include: foam, sponge, suppositories,
creams, film
• Spermicide: chemical that kills sperm
(nonoxynol-9)
• Cost: $0.85 per application
• Advantage: no prescription necessary
• Disadvantages:
– Interruption of sexual experience (except
for the sponge)
– Skin irritation (which can increase
susceptibility to STI infection)
– No protection from STIs
– Not effective enough to be used w/o a
condom or other method
20. Cervical barrier devices
• Covering the cervix is one
of the oldest methods in
contraceptive history
– Casanova (18th century Europe)
promoted using squeezed-out
lemon half; European women
shaped beeswax to cover cervix
• Cervical cap: covers cervix only
• Diaphragm: covers upper vaginal
wall behind cervix underneath pubic bone
• FemCap & Lea’s shield have removal straps
• Lea’s Shield allows a one-way flow of fluid from cervix
to vagina
• Method is usually combined w/spermicide
diaphragm Cerv cap
Lea’s shield
FemCap
21. How to use cervical barrier devices
• Diaphragm & cervical cap: need to be fitted (may need to be refitted
w/weight gain or loss >10 lbs.)
• FemCap & Lea’s Shield do not have to be fitted, but still require a
prescription in the U.S.
• Use diaphragm & cervical cap only with water-based lubricants b/c
they are latex (FemCap & L.S. are silicone)
• Can insert up to 6-8 hr. before intercourse; should leave in at least 8
hr after
23. Intrauterine Devices (IUDs)
• Small plastic objects inserted
into uterus
• 2 types
– Hormone-releasing (progesterone)
– Copper-releasing
• Have fine plastic threads
attached that hang slightly
out of cervix into vagina for removal
• Very high continuation rate (how many women are
still using it one year after starting) compared w/other
methods
progesterone
24. IUD Mechanisms of Action
Levonorgestrel-Releasing
IUD
(LNG-IUS, Mirena®
)
– Inhibits fertilization
– Thickens cervical mucous
– Inhibits sperm function
– Thins and suppresses the
endometrium
Jonsson B, et al. Contraception. 1991;43:447-458; Videla-Rivero L, et al. Contraception.
1987;36:217-226; Kulier R, et al. Cochrane Database Syst Rev. 2006;3: CD005347.
Copper-Releasing IUD
(ParaGard®
T380A)
– Inhibits fertilization
– Releases copper ions (Cu2+
)
that reduce sperm motility
– May disrupt the normal
division of oocytes and the
formation of fertilizable ova
25. Costs, pros, & cons of IUDs
• Costs
– Copper: $550 (good for up to 10 years)
– Hormone: $500-$700 (good for up to 5 years)
• Advantages
– Very effective (essentially no “user error”)
– Long-term protection
– No interruption of sexual activity
– Don’t have to remember to use
– Can be used during breast-feeding
• Disadvantages
– No STI protection
– Risk of PID (usually within first 1-2 months following insertion)
– Rare incidence of perforating uterine wall
26. Emergency Contraception
• Works mainly by preventing ovulation or fertilization
• In theory, can also interfere w/implantation
– Evidence suggests this is not primary mechanism of action
• If it was, efficacy should not decrease w/short-term delay, as long
as EC was administered some time before implantation
• However, EC is increasingly less effective w/delay
• Oral contraceptive pills
– 95% effective within 24 hrs; 75% effective within 72 hrs
– Preven: 2 doses of combined estrogen & progesterone
– Plan B: 2 doses of progesterone
– Other combinations of oral contraceptives can substitute for
these (see Table 10.7, p. 283)
• Copper-T IUD
– 99% effective if inserted within 5 days
27. Standard Days Method (w/Cyclebeads)
Arevalo M et al., Contraception, 2002;65:333-338.
On WHITE bead days
you can get pregnant.
Avoid unprotected
intercourse to prevent
a pregnancy.
On the day you start your
your period, move the
ring to the RED bead.
Every morning
move the ring
to the next
bead.
Always move
the ring from
the narrow to
the wide end.
1
2
Also, mark this date
on your calendar
When you start your
next period, move the
ring directly to red
bead and begin again.
On BROWN bead
days you can
have intercourse
with very low
probability of
pregnancy.
If you have not started
your period by the day
after you put the ring on
the last brown bread,
contact your provider.
If you start
your period
before you put
the ring on the
darker brown
bead, contact
your provider.
(may not be a good
method for you)
29. Calendar or Rhythm Method
Low-risk DaysLow-risk Days
Egg may still
be present OvulationOvulation
1414 13131616
1515
1717 1212
11
11
These days may be
unsafe if 28-day cycle
varies as much as 8-9
days between shortest
and longest cycles.
44
1010Intercourse on these days
may leave live sperm to
fertilize egg.
33
2211
99
88
77
66
55
2828
2727
262625
25
2424
2323
222221212020
1919
18
18
Billings JJ. Med J Aust. 1978;2:436.
Byer/Shainberg/Galliano. Dimensions of Human Sexuality,
5e. 1999, The McGraw-Hill Companies, Inc.
30. Basal Body Temperature Method
• BBT=body temp in resting state on waking
• Slight drop immediately before ovulation
• After ovulation, release of progesterone
causes slight increase in temperature
31. Fertility Awareness Methods
pros & cons
• Pros:
– Essentially free
– No medical side effects
– Does not interrupt sexual activity
– Woman gains awareness about her body and natural
cycles, which can increase comfort w/sexuality
– Acceptable to Catholic Church
• Cons:
– No STI protection
– Requires some degree of discipline in order to keep track
of calendar/charts, etc.
– Need to abstain from intercourse or use a backup
method during fertile days
32. Sterilization
• Essentially permanent, although vasectomies are
sometimes reversible
• Does not affect hormones, desire, sexual functioning
• Female sterilization
– Tubal sterilization: fallopian tubes are severed to block
passage of sperm & eggs
– Transcervical sterilization: tiny coil inserted through cervix
into fallopian tubes
• Coil promotes tissue growth that, after 3 months, blocks fallopian
tubes
• Male sterilization (vasectomy)
– Safer, less expensive, fewer complications than female
sterilization
– Cutting and closing vas deferens (ducts that carry sperm)
33. Ex. of female sterilization procedure
• Laparoscope: narrow, lighted viewing instrument that is
inserted into abdomen to locate the fallopian tubes
34. Ex. of male sterilization procedure
• Vas deferens on
each side is cut;
small section is
removed, and the
ends are tied off or
cauterized
35. Less than Effective Methods
• Nursing
– amenorrhea is common for a brief period after birth while
breastfeeding
– 80% of women ovulate before first period (and so do not
know that they are fertile)
• Withdrawal before ejaculation
– difficult to judge when to withdraw
– anxiety may lower pleasure for both partners
– Cowper's gland fluid may carry sperm
– any sperm on vulva may travel into vagina/uterus
• Douching
– sperm reach uterus in 1-2 minutes
– douching may speed sperm along
– irritates vaginal tissue
36. New Directions in Contraception
for men
• The “male pill”: Testosterone & progestin
may lower sperm count
• New forms of reversible vasectomy
– Injection of a blocking gel into vas deferens; gel
is dissolved to reverse the procedure
– Insertion of two plugs into each vas deferens--
can be removed later
37. • Most new developments are improvements
on existing contraception for females
– Variations on methods of delivery, formulation of
hormones
– New designs of IUDs, female condoms
– spermicides with microbicides (to kill microbes
that cause STIs)
New Directions in Contraception for
women
Editor's Notes
Intrauterine Contraceptives: Mechanisms of Action The primary method of action in intrauterine contraceptives (IUDs) is to prevent the fertilization of ova, which is supported by the low rate of ectopic pregnancies among users.The mechanisms of action of the levonorgestrel-releasing intrauterine system (LNG-IUS, Mirena®) are similar to that of levonorgestrel implants or levonorgestrel-containing mini-pills. The LNG-IUS has several different contraceptive actions: thickening of the cervical mucus; inhibition of sperm capacitation, survival, and motility; suppression of ovulation in some women; endometrial thinning; and stimulation of an inflammatory reaction that may impede sperm function and prevent implantation. A high concentration of levonorgestrel in the endometrium leads to increased endometrial atrophy that, in turn, results in a substantial reduction in menstrual flow or in amenorrhea in some users. The release of copper ions (Cu2+) from the ParaGard® IUD is believed to affect sperm motility and viability which impairs fertilization, and to disrupt the normal division of oocytes and the formation of fertilizable ova. Changes also occur in the endometrium that could interfere with the implantation of a fertilized ovum, which explains why this device is particularly effective as a method for emergency contraception. References:
Jonsson B, Landgren BM, Eneroth P. Effects of various IUDs on the composition of cervical mucus. Contraception. 1991;43:447-458. Videla-Rivero L, Etchepareborda JJ, Kesseru E. Early chorionic activity in women bearing inert IUD, copper IUD and levonorgestrel-releasing IUD. Contraception. 1987;36:217-226.Kulier R, Helmerhorst FM, O'Brien P, Usher-Patel M, d'Arcangues C. Copper containing, framed intra-uterine devices for contraception. Cochrane Database Syst Rev. 2006;3:CD005347.
Standard DaysTM Method
The Standard DaysTM method of contraception is based on a formula that accounts for natural variations in the length of the menstrual cycle and the occurrence of ovulation within the cycle (26 to 32 days). Accordingly, women are to abstain from unprotected intercourse between days 8 and 19 of their menstrual cycle. To use this method successfully, however, a woman must have no more than 2 cycles a year that are outside the 26- to 32-day range. This stipulation renders this method unfeasible for approximately 25% of women.With correct use during the first year, 5% of women who use this technique risk an unintended pregnancy. With typical use, the risk of unintended pregnancy during the first year of use increases to 12%. A set of color-coded set beads, called Cycle BeadsTM, help users track their menstrual cycle and the days they are likely to become pregnant.References:
Arevalo M, Jennings V, Sinai I. Efficacy of a new method of family planning: the Standard Days Method. Contraception. 2002;65:333-338.
Hatcher RA, Trussell JA, Stewart F, Cates W, Stewart GK, Guest F, Kowal D, eds. Contraceptive Technology. 18th rev. ed. New York: Bridging the Gap Communications; 2004.
CycleBeads™ and Standard Days™ are trademarks of Georgetown University. CycleBeads are a patented product and are used by Cycle Technologies under license. Website located at www.cyclebeads.com. Accessed September 11, 2006.
Cervical Mucous Method
This method relies on the female becoming familiar with and tracking the changes in her cervical mucous. The amount of cervical mucous increases and becomes slipperier, stretchier, and clearer as the fertility window approaches during the course of the normal menstrual cycle. These changes are sufficiently predictable, and the quality of the mucous on the day before ovulation is directly related to the risk of conception. With correct use, it is estimated that 3% to 4% of women experience an unintended pregnancy during the first year of using this method.This method is not appropriate for patients who produce little or no cervical mucous or who cannot interpret its changes. Douching, spermicides, lubricants, and semen can interfere with recognizing the correct characteristics of cervical mucous.
Reference:
Stanford JB, Smith KR, Dunson DB. Vulvar mucous observations and the probability of pregnancy. Obstet Gynecol. 2003;101:1285-1293.
Calendar or Rhythm Method
The simplest and perhaps the least accurate method of determining the window of fertility in the menstrual cycle is the calendar or rhythm method, sometimes called the fixed days method. To use this method, a woman must first determine the length of her shortest and longest cycle by measuring it for 6 to 12 months. Then, to determine the first and last day of fertility in her average cycle, she subtracts 18 days from the shortest cycle and 11 days from the longest, respectively. To avoid becoming pregnant, she avoids unprotected intercourse from days 8 through 21 of her menstrual cycle. With perfect use during the first year, 9% of women using these techniques experience an unintended pregnancy.
References:
Billings JJ. Natural family planning. Med J Aust. 1978;2:436.
Hatcher RA, Trussell JA, Stewart F, Cates W, Stewart GK, Guest F, Kowal D, eds. Contraceptive Technology. 18th rev. ed. New York: Bridging the Gap Communications; 2004.
Byer/Shainberg/Galliano. Dimensions of Human Sexuality, 5e. 1999, The McGraw-Hill Companies, Inc.
Basal Body Temperature Method
Basal body temperature, the body’s waking/resting temperature dips and then begins to rise approximately 3 days before ovulation during the course of the normal menstrual cycle. Women are considered to be fertile from the beginning of the temperature rise until 3 days after a sustained increase of at least 0.4 degrees Fahrenheit (0.2 degrees Celsius). However, this is not an accurate method of estimating the fertility window, since ovulation can only be identified in retrospect. Nonetheless, with perfect use, it is estimated that only 5% of women experience an unintended pregnancy during the first year with this method.
Patients should be counseled to track their basal body temperature for 3 months before relying on this contraceptive method. Computerized devices that pool temperature data from several cycles have been developed to assist women who use this technique.References:
1. Frackelton B. Hormonal Forecaster. Available at: http://www.hormonalforecaster.com/captures.html. Accessed September 10, 2006.
2. Hatcher RA, Trussell JA, Stewart F, Cates W, Stewart GK, Guest F, Kowal D, eds. Contraceptive Technology. 18th rev. ed. New York: Bridging the Gap Communications; 2004.
