Contraception
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Pearl index: The effectiveness of any method of contraception is measured by the number of unwanted pregnancies
that occur during 100 women years of exposure, i.e. during 1 year in 100 women who are normally fertile and are
having regular coitus.
MOAs:
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Prevent ovulation (pill, patch, vaginal rings, progesterones)
Prevent sperm reaching oocyte (female and male sterilisation)
Prevent embryo implantation in the uterus (Cu-IUD and LNG-IUS)
Poisoning sperm (spermidcides)
Allow sperm to enter vagina but block further passage (diaphragm + cap, progesterones)
Prevent sperm entering the vagina (condoms, FABs)
Barrier methods
Condoms
Diaphragms and cervical caps
MOA
Combined and triphasic pills act by suppressing gonadotrophin-releasing hormone (GnRH) and gonadotrophin secretion and, in
particular, suppressing the luteinizing hormone peak, and thus inhibiting ovulation. The endometrium also becomes less
suitable for nidation and the cervical mucus becomes hostile. Progesterone-only pills act predominantly to reduce the amount
and character of the cervical mucus, although they do alter the endometrial maturation as well. Ovulation is completely
suppressed in only 40% of women.
Hormonal contraception
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2 types:
1. Combinations of oestrogen with a progestogen (combined pill)
2. Progestogen alone (progestogen-only pill)
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Combined pill (oestrogen + progesterone) 91% effective because pills are often forgotten or missed, but otherwise is
99.7% effective
Extremely effective
Can also be used to reduce AUB. Thinner endometrium, restablish predictable bleeding patterns, can manipulate
your cycle
Main MOA: inhibition of progesterone + oestrogen on the pituitary, with the suppression of FSH and LH
Preparation is chosen with the lowest oestrogen and progestogen content that is well tolerated and gives good
cycle control in the individual woman
Taken for 21 days followed by 7 pill-free days (sugar tablets, prevents long term suppression of HPG axis which could
make fertilisation difficult), which causes a withdrawal bleed. No reason why women cant take the pill continuously
(however can help thin the endometrium)
Normal menstruation usually commences fairly soon after discontinuing treatment, and permanent loss of fertility is
rare
Preparations are monophasic (same doses of hormones throughout), but some are phasc (dose varies) – no
advantagement of phasic over monoophasic
Produces a ‘pseudo’ (hormonally) pregnant state incompatible with fertilisation. No ovulation takes place.
If 2 or more pills are missed, this puts the woman at risk of ovulation. Additional contraceptive cover during the next 7
days of pill taking is advised (condoms, abstinence) -> there are instructions depending on when this took place.
One pill missed ->The missed pill should be taken as soon as it is remembered, remaining pills continued at their usual
time.
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2 pills missed (more than 48 hours late) -> most recent missed pill should be taken ASAP, remaining pills should be
continued at usual time. Condoms should be used or sex avoided until 7 pills consecutive active pills have been taken.
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Can also use hormonal trandermal patch
Hormonal ring – flexible ring that releases estradiol + rogesterone daily -> worn in the vagina. 21 days, then 7 ring free
days.
Mode of action:
Oestrogen inhibits secretion of FSH via negative feedback on anterior pituitary, and thus suppresses development
of ovarian follicle
Progestogen inhibits secretion of LH and thus prevents ovulation, also makes cervical mucus less suitable for
ovulation (prevents sperm entry)
Act together to alter the endometrium in a way that discourages implantation
May interfere with contractions of cervix, uterus, fallopian tubes that facilitate fertilisation and implantation
Common adverse effects: weight gain (fluid retention or anabolic effect), mild nausea, flushing, dizziness, depression,
irritability, skin changes (acne, pigmentation), amenorrhoea of variable duration on cessation of taking the pill
Reduces risk of colorectal cancer, endometrial, ovarian cancer. Increased clotting tendencies (reduced with combined
pill – reduced dramatically by progesterones) Increased risk of breast cancer, increase risk of cervical cancer
Beneficial effects: avoiding unwanted pregnancy, decreased menstrual symptoms like irregular periods and
intermenstrual bleeding, iron deficiency anaemia, premenstrual tension are reduced, benign breast disease, uterine
fibroids, lower incidence of PID and benign ovarian cysts, improves acne
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CIs
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The absolute contraindications include pregnancy, previous pulmonary embolism or deep vein thrombosis, genetic
thrombophilia, CV disease, uncontrolled HTN, sickle-cell disease, porphyria, current active liver disease or previous
cholestasis (particularly where it is associated with a previous pregnancy), migraine associated with an aura
(increased stroke risk) or carcinoma of the breast/genital tract,
It is necessary to maintain a high level of vigilance in women with varicose veins, diabetes, hypertension, renal
disease and chronic heart failure, migraines with aura, but none of these conditions constitutes an absolute
contraindication and, in some cases, the adverse effects of a pregnancy may substantially outweigh any hazard from
the pill.
Women who smoke and are also over the age of 35 years have a significantly increased risk of coronary artery and
thromboembolic disease, advise progesterone only instead (mirena)
S/Es The occurrence of migraine for the first time, severe headaches or visual disturbances, or transient neurological changes
are indications for immediate cessation of the pill. There are a series of minor side effects that may sometimes be used to
advantage or may be offset by using a pill with a different combination of steroids
Major S/Es
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Venous thrombosis + arterial disease. Women who are undergoing long distance travel should take appropriate
exercise on the journey and consider wearing graduated compression stockings
Although some reports have suggested there is a small increase in the relative risk of breast (relative risk 1.24) and
cervical cancer (relative risk 1.5–2) in pill users, especially if it is commenced before a first pregnancy, the breast
cancer increased risk is not definitely proven, and the cervical cancer risk is probably due to the incidence of wart
virus infection and not the taking of the oral contraceptive pill (OCP).
COCPs are contraindicated in women with a current or past history of VTE or a known thrombogenic mutation. Other risk
factors to exclude before prescribing a COCP include:
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a family history of VTE or thrombophilia in a first degree relative
obesity (body mass index [BMI] 35 kg/m2 or greater)
prolonged immobilisation
being under 21 days post partum.
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COCP metabolised by cp450 – drugs that upregulate this system can reduce concentrations of relevant contraceptive
hormones, resulting in pregnancies. Interactions with St John's wort, griseofulvin, protease inhibitors and older
antiepileptic drugs (eg phenytoin, carbamazepine, primidone) are commonly reported.
Current evidence suggests that most antibiotics do not interact with combined hormonal contraceptives. The only
exception is for those that induce liver enzymes (ie rifabutin, rifampicin). When taking either of these antibiotics, no
combined hormonal contraceptive at any dose can be considered effective—alternative methods (eg intrauterine
contraception) need to be considered.
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When should it be commenced?
It is best commenced on day 2–3 of the next period but can be commenced at any time. Many combined pills include 7 days of
placebo (‘sugar’) tablets so that the user takes a pill every day of the month and so reduces the risk of forgetting when to
restart the pill after the normal 7 ‘pill free’ days each cycle (sometimes labelled ‘ED’ or everyday preparations). Each tablet
including the placebos are labelled with a day of the week in these calendar packs with the placebos being a different colour.
With these pills a woman should start taking the pill on the first day of her next period starting with the inactive tablet
corresponding to the current day of the week. When changing from a higher to a lower dose pill preparation women should be
advised to start taking the active tablets of the new pill immediately on completing the last tablet of her previous pill, omitting
the normal 7 day gap
Pills and surgery
The pill increases the risk of deep vein thrombosis and should therefore be stopped at least 6 weeks before major surgery. It
should not be stopped before minor procedures – particularly before laparoscopic sterilization procedures. The risk of an
unwanted pregnancy occurring before admission is substantially greater than the risk of thromboembolism.
Progesterone only methods (99.7% effective if taken perfectly, but in real life only 91% because pills can be
forgotten/missed)
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Pill
Taken daily without interruption
Mode of action is mainly on cervical mucus, thickens it so it is inhospitable to sperm, also hinders implantation due
to thinning effects on endometrium and decreasing mobility/secretions of fallopian tubes. They act on the
hypothalamus and suppress pituitary LH surge and may inhibit ovulation.
Main MOA is via mucus, not as much in inhibiting ovulation
Beneficial effects: suitable alternative to combined pill in women in whom it is contraindicated or women whose
blood pressure increases unacceptably during oestrogen treatment, or in those who are breastfeeding
Unwanted effects: contraceptive effect less reliable than pill and missing a dose may lead to contraception,
disturbances of menstruation are common especially irregular bleeding (periods may be normal, less frequent, may
be spotting between), long-term safety data is Low dose POP – only inhibits 50% of cycles. Mainly rely on thickening
of cervical mucous. Low dose pills inhibit ovulation in less than half the cycles
Must be taken within a small window at same time each day (3hr window) – due to low dose. Strict concordance is
essential due to its effect on vaginal mucus, which can be lost if the POP is delayed for even a few hours, it doesn’t
reliably suppress ovulation
S/E: weight gain, mood changes, acne, loss of libido, persistent follciles (simple cysts)
If a pill is missed then the woman should continue taking the POP and use extraprecautions for the next 48 hours until
the progesterone effect of the mucus builds up
When taking the POP while breastfeeding, irregular bleeding may signify the return of ovulation and fluctuating
hormone concentrations. Other causes (eg pregnancy, Chlamydia trachomatis infection) need to be excluded. As long
as the POP is being taken correctly, this method of contraception can be continued. If a woman finds the bleeding
unacceptable, she can switch to another progestin-only contraception method (eg etonogestrel implant, intrauterine
system).
Take pill continuously
S/E – simple ovarian cysts, irregular bleeding, acne, headaches, breakthrough bleeding, tender breasts
Implant (Implanon, Dep-Provera) (progesterone only) (99.9% effective)
Subdermally in medial epicondyle, in 1st 5 days of the menstrual cycle
Provides contraception for three years, can remove at any time
MOA – stops ovaries from releasing an egg each month
Releases steady low dose progesterone
Main A/E – irregular bleeding patterns, amenorrhoea in 22%. However, they may cause irregular bleeding or
amenorrhoea, which can be a source of anxiety because of the possibility of pregnancy
1:5: unpredictable bleeding, 1:5 no bleeding, 3:5 somewhere in the middle
each of these injectable preparations works by making the cervical mucus hostile, the endometrium hypotrophic and
by also suppressing ovulation.
Fertility restored immediately after removal
Sometimes manage with pill to control bleeding
Injection (99% effective, 94% if youre late for injection)
depot injection of medroxyprogesterone acetate – IM or SC
inhibit ovulation
every 12-14 weeks get injection
50% amenorrhoea rates per year
Inhibits ovulation
May delay return of fertility after discontinuation (make take up to 1 year after last injection for ovulation to return)
The first injection should be given during the first 5 days of the menstrual cycle, because this provides immediate
contraceptive protection.
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S/E – possible weight gain
After stopping DMPA the time for fertility to return varies, due to persisting anovulation. The effect on fertility is not
permanent. The median conception time is 8 to 10 months after the last injection. Seventy-eight per cent of women
wanting to conceive do so within 12 months of their most recent injection, and 95% within 2 years.
Some women have erratic and prolonged bleeding as DMPA wears off after their last injection. A COCP can be used to
maintain regular cycles during DMPA withdrawal, if pregnancy is not desired.
Only hormonal method that may delay return of fertility after discontinuation - As with all progestin-only forms of
contraception, the main adverse effect of DMPA is unpredictable bleeding patterns. Other possible adverse effects
are weight gain, acne, mood changes, depression and increased risk of bone loss (with prolonged use). The decline in
bone mineral density associated with DMPA is reversible, but its use in two populations has potential concern.
Progestin only contraception – Cis
Progestin-only contraception is contraindicated in women with active breast cancer within the last 5 years, but has relatively
few other contraindications. The harms outweigh the benefits in the following conditions: antiphospholipid antibodies with
systemic lupus erythematosus, unexplained vaginal bleeding, ischaemic heart disease or stroke, severe cirrhosis or
hepatocellular carcinoma.
Emergency contraception
Oral
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After unprotected intercourse, missed combined pill or a burst condom, a single 750 mg levonorgestrel tablet is
taken within 72 hours of intercourse, followed by a second dose exactly 12 hours later. 96 hours after unprotected
sex is effective
The levonorgestrel-only method has fewer side effects than the previously used combined method and, in some
countries, is available to women over the age of 16 years directly from pharmacists. Side effects include mild nausea,
vomiting (an additional pill should be taken if vomiting occurs within 2–3 hours of the first dose) and bleeding.
Work by delaying ovulation so that the sperm present in the reproductive tract will have lost the ability to fertilise the
oocyte when it is eventually released
Oral EC is much less effective than CU-IUD for EC and is estimated to prevent only 2/3 of pregnancy
Another option is progesterone receptor modular ulipristal aetate – 96 hours after unprotected sex
Cu-IUD
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Most effective method
Its effect on endometrium is thought to prevent implantation if fertilisation has occurred
Since the blastocyst implants 6-10 days after the fertilisation, it can be inserted up to 5 days after unprotected sex or
5 days after predicted ovulation
Can be used in emergency contraception
S/E- pills can be heavier and more painful
Non-medical methods of contraception
The most fertile phase of the menstrual cycle occurs at the time of ovulation. In a 28-day cycle, this occurs on day 13 or 14 of
the cycle. The fertile phase is associated with changes in cervical mucus that a woman can learn to recognize by selfexamination and hormone changes that can be measured by home urine testing kits. Avoidance of the fertile period can be an
extremely effective method in well-motivated couples.
Natural methods of family planning include the following:
• The rhythm method: Avoiding intercourse mid-cycle and for 6 days before ovulation and 2 days after it. The efficacy of this
method depends on being able to predict the time of ovulation. If a regular 28 day cycle occurs, ovulation is predicted for day
14, and abstinence should be from days 8 to 16. If the cycles are very variable, varying between 24 and 32 days, the earliest
ovulation would be on day 10 and the latest on day 18, so abstinence would be required between days 4 and 20.
• The ovulation method : This method takes into account the ability of a woman to recognize the increase in vaginal wetness
due to cervical mucus productionin the phase before ovulation, and abstaining from sex during that time and for 2 days after
the peak wetness has been observed. This method is much better than the rhythm method, but many women only get 4 days
advanced warning of the time of ovulation, so intercourse on the preceding 2 days can result in a pregnancy.
• Coitus interruptus (withdrawal): A traditional and still widely used method of contraception that relies on withdrawal of the
penis before ejaculation. It is not a particularly reliable method of contraception, because the best sperm often reach the tip of
the penis before the male experiences the imminent ejaculation, or he forgets in the ‘heat’ of the moment.
• Lactational amenorrhoea method: Breastfeeding has historically been the most important means of family ‘spacing’.
Ovulation resumes on average 4–6 months later in women who continue to breastfeed. During the first 6 months after birth
this is an effective method of contraception in mothers providing they are fully breastfeeding, not giving the baby any nonbreast milk or other food, AND have remained amenorrhoeic, with failure rates as low as 1/100 women being seen
Intrauterine contraceptive device
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These devices have the advantage that, once inserted, they are retained without the need to take alternative
contraceptive precautions. It seems likely that they act mainly by preventing fertilization. This is a result of a
reduction in the viability of ova and the number of viable sperm reaching the tube.
Progesterone releasing intrauterine system (99.8% effective)
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Release the progesterone levonorgesterel into the uterus
Mirena (LNG-IUS) – 5 years of contraception
Exerts a potent hormonal effect on the endometrium, preventing endometrial proliferation + implantation, also
has thickening of the mucus
It does not prevent ovulation – in first few months women may have unpredictable bleeding. Usually improves with
time and get lighter/absent periods
It should be inserted in the first 7 days of the menstrual cycle, 6 weeks post partum, can be inserted at any time, as
long as are certain woman is not pregnant
Reduces HMB + dysmenorrhoea
Most common S/E – acne, breast tenderness, mood disturbance, headaches
Most notable effect is reducing HMB, more effective than COCP and transaexamic acid at this
Also beneficial for dysmenorrhoea, pain with endo, adenomyosis, protect endometirum from hyperplasia
S/E – can be painful when inserting especially if haven’t given birth before
Cu-IUD (99%)
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Duration of use between 3-10 years
The addition of copper to a contraceptive device produces a direct effect on the endometrium by interfering with
endometrial oestrogen-binding sites and depressing uptake of thymidine into DNA. It also impairs glycogen storage in
the endometrium
Stimulates inflamm reaction in the uterus, effects are toxic to both sperm + egg
May experience painful or heavier menses. Can be tolerated by most, However, in 15% of such women it is
sufficiently severe to necessitate removal of the device. It can be controlled by drugs such as tranexamic acid or
mefenamic acid
If pregnancy occurs with it in-situ, an USS should be conducted to exclude ectopic pregnancy
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Advisable that IUDs should be removed before 12 weeks gestation in view of the greater risk of miscarriage, preterm
delivery, septic abortion and chorioamntiotis if the device is left in situ
Risks
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Associated with risks:
 Perforation (increased risk if breastfeeding/less than 6 months post partum)
 Expulsion (1 in 20 will be expelled in first 3 months, but after this, risk decreasesz0
 Infection (risk of infection in first 3 weeks following insertion is low)
 Missing threads (indicates pregnancy, expulsion or perforation) – pregnancy test done and emergency
contraception given
 If do fall pregnant, then risk of ectopic pregnancy is high,., should be removed before 12 weeks gestation in view
of greater risk of miscarriage/preterm delivery/septic abortion/chorioamnionitis
Pre-existing PID is a contraindication to this method of contraception. There is a small increase in the risk of acute PID
in IUD users, but this is largely confined to the first 3 weeks after insertion. If PID does occur, antibiotic therapy is
commenced and, if the response is poor, the device should be removed.
Pelvic pain - Pain occurs either in a chronic low-grade form or as severe dysmenorrhoea. The incidence is widely
variable, with up to 50% of women suffering some pain. However, the pain may be acceptable if it is not severe, and
this is a decision that has to be made by the patient in relation to the convenience of the method.
Vaginal discharge – slightly watery/mucoid discharge
Erratic bleeding and spotting. specially in the first 3 to 5 months, but blood loss decreases dramatically over 6 months.
Amenorrhoea or light bleeding occurs in up to 65% of women after 12 months of use.
Women should be reviewed 4 to 6 weeks after the LNG-IUS has been inserted, to:
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exclude post-insertion pelvic inflammatory disease (rare)
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ensure the strings attached to the LNG-IUS have not lengthened (suggesting partial expulsion).
Women should be reviewed annually after that. They should be told to return immediately if they develop:
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pelvic pain
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pain during intercourse
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a dramatic change in bleeding patterns, after initial changes settle.
Sterilisation
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Women should be advised to continue to use other contraception until the period occurs following the sterilization
procedure. Men should be advised to use alternative contraception until they have had two consecutive semen
analyses showing azoospermia 2–4 weeks apart, with these analyses not done until at least 10 ejaculations have
occurred.
Timing of sterilisation
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Can be done anytime in the cycle but done in follicular phase
A pregnancy test should be performed preoperatively if a woman has a late or missed period or thinks she may be
pregnant.
Lap sterilisation
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The majority of procedures involves interruption of the Fallopian tubes but may vary from the application of clips on
the tubes to total hysterectomy. In general terms, the more radical the procedure the less likely there is to be a
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failure. However, very low failure rates can now be achieved using methods with high reversibility prospects and
these should be the methods of choice.
Effective contraception is required until the menstrual period following lap procedure or 3 months following
hysteroscopic procedure
Method is considered as irreversible, failure rate 1:200 lap, 1:400 hysteroscopic, risks and complications (1:1000 risk
of traumat o bowel, bladder, blood vessels)
Vasectomy is safter, quicker, easier, less morbidity
It does not protect against STIs
Pregnancy is extremely rare, but there is an increased risk of ectopic
Reversal is highly skilled, cannot be performed after hysteroscopy csterilisation, and if conducted effectively after lap,
then it is associated with an increased risk of ectopic pregnancy
emember the reported failure rate for third-generation/levonorgestrel IUDs is comparable to that of sterilization but
male sterilization has a significantly lower failure rate.
Apart from the complications of laparoscopy, if it was performed to enable sterilization, the longer-term complications of any
tubal sterilization are tubal recanalization and pregnancy, ectopic pregnancy, menstrual irregularity and loss of libido. Apart
from the complications of laparoscopy, if it was performed to enable sterilization, the longer-term complications of any tubal
sterilization are tubal recanalization and pregnancy, ectopic pregnancy, menstrual irregularity and loss of libido.
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Tubal clips
 Most widely used
 Advantage: minimal damage to the tube, disadvantage – higher failure rate
 1:200 failure rate
Tubal coagulation and division
 Sterilization is effected by either unipolar or bipolar diathermy of the tubes in two sites 1–2 cm from the
uterotubal junction. A considerable amount of tube can be destroyed with this technique. Division of the
diathermied tube is said to reduce the risk of ectopic pregnancy. The failure rate depends on the length of tube
destroyed.
 Because of the risk of thermal bowel injury with subsequent leakage and faecal peritonitis, diathermy should not
be used as the primary method of sterilization unless mechanical methods of tubal occlusion are technically
difficult or fail at the time of the procedure.
Tubal ligation
 These procedures are usually performed through a small abdominal incision (mini-laparotomy) or at the time of
caesarean section. They are less widely used with the increase in laparoscopic procedures. Even when
laparoscopy is contraindicated for some reason it is still more common now to use clips to occlude the tubes.
Hysteroscopic sterilisation
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Outpatient procedure
This procedure consists of insertion of a small device into each tube at the time of a hysteroscopic examination, with
this device resulting in fibrosis and ultimate occlusion of the tube on each side. This insertion can often be done
without anaesthesia and does not require a laparoscopy
Timing
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The operation can be performed at any time in the menstrual cycle, but is best done in the follicular phase of the
cycle. A pregnancy test should be performed preoperatively if a woman has a late or missed period or thinks she may
be pregnant.
Vasectomy
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Performed under LA
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Two small incisions are made over the spermatic cord and 3–4 cm of the vas deferens is excised . The advantage of
the technique is its simplicity. The disadvantages are that sterility is not immediate and should not be assumed until
all spermatozoa have disappeared from the ejaculate. On average, this takes at least 10 ejaculations.
Post vasectomy semen analysis should be conducted at 12 weeks to confirm the absence of sperm in ejaculate.
Harder to reverse than female sterilisation
Failure rate 1/2000
Safer, quicker, less morbidity
Risk of scrotal haematoma and infection with this procedure
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Condoms
Failure rate 24%
98% effective, but less effective in real life (82%) as break/not always used correctly
Preventing against STIs
Diaphragm and cap
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18% failure rate
82-86% effective
Withdrawal method
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78-96% effective, not recommended