Presentation on theme: "CONTRACEPTION AND STERILIZATION By DR. MALAK AL-HAKEEM Associate professor& consultant obstetrics and gynecology."— Presentation transcript:
CONTRACEPTION AND STERILIZATION By DR. MALAK AL-HAKEEM Associate professor& consultant obstetrics and gynecology.
The ideal method should be: 1. Certain 2. Without risk to health, 3. Ethically, religiously acceptable & Inexpensive
The effectiveness (or failure rate) of a particular method of contraception is usually expressed by the “ Pearl index ”, which states the number of unwanted pregnancies that occur in 100 women using that method for a year.
COITUS INTERRUPTUS Withdrawal of the penis at the moment before ejaculation is a widely used method although the failure rate is high (index 20 to 30).
THE SAFE PERIOD It is far from reliable (index 20 to 30). The method is based on the assumption that the ovum is capable of being fertilized for only 24 hours after its release, and that sperm can fertilize the ovum for only 72 hours after they are deposited in the vagina.
Day 1Day 14Day 28 Day 9Day 17 Ovulation Safe THE SAFE PERIOD
In women with variable cycles unsafe period is determined by subtracting 18 days from the shortest cycle and 11 days from the longest cycle.
Detection of time of ovulation 1. Basal body temperature 2. Cervical mucus study 3. LH surge in urine (36 hours before ovulation) the most accurate test.
CONDOM This method is that most widely used in the UK because of its simplicity. The latex rubber sheath should be used with a chemical spermicide for additional contraceptive security.
Occasional failures occur because 1. The sheath is defective, 2. It is not worn in the earlier phases of coitus, or 3. It slips from the penis after ejaculation (index quoted 4 to 10). It’s use reduces the risk of venereal infection and is particularly important in controlling the spread of HIV infection.
OCCLUSIVE DIAPHRAGM (DUTCH CAP) USED WITH SPERMICIDE This can be an efficient method if it is used carefully and intelligently. The diaphragm is inserted before intercourse, and should not be taken out for at least 6 hours afterwards, so that the spermicide will kill any spermatozoa before its removal.
OCCLUSIVE DIAPHRAGMS AND CAPS Vaginal diaphragm
This method has the advantage that it is entirely the woman ’ s responsibility. It is not as reliable as the oral pill or intrauterine device, but many women prefer to use it because of the absence of side effects.
CERVICAL CAP This is a small, firm cup-shaped rubber cap, which fits over the cervix. It needs careful fitting.
SYSTEMIC CONTRACEPTIVES Systemic contraception, operating through its effect on the endocrine system, was first introduced in 1956 in the form of an oral preparation containing a synthetic oestrogen and a synthetic progestogen – the combined pill.
The chief advantage of this method is that intercourse can take place at any time. Provided that the pills are taken it is probably the most reliable of all contraceptive methods (indices quoted 0.1 to 1.5). The disadvantage is that she must remember to take the pill every day.
Mode of action The oestrogen and progestogen components of the pill inhibit ovulation through the feedback system that controls hypothalamic- pituitary-ovarian function. Production of GnRH is inhibited, so FSH and LH are suppressed.
Contraceptives containing progesterone make the cervical mucus thick, viscid and scanty. It causes endometrial changes, so it becomes hostile to implantation. Also, it inhibits capacitation of spermatozoa that is necessary for fertilization
Formulations The combined pill contains one of two synthetic oestrogens- ethinyloestradiol or menstranol. Although a variety of synthetic progestogens are used, they are all derivatives of 19-nortestosterone.
The doses and proportions vary in the different proprietary preparations. Because certain thrombo-embolic complications have been related to the oestrogen component of the pill, most tablets now contain less than 50 micrograms.
Patterns of administration Vary with the different preparations. The commonest regimen starts on day 5 of a cycle; a pill is taken each day for 21 days. There is then a 7-day interval during which no pills are taken (unless the maker includes 7 placebo pills in the pack).
During the interval withdrawal bleeding usually occurs, but even if it does not the woman starts the next course of pills after 7 days. The pill should be taken at the same time each day. If the woman forgets to take the pill one night she can take it the next morning. She should be warned that ovulation may not be inhibited in the first cycle.
Slight bleeding whilst taking the tablets can be ignored unless it is repeated, in which case full investigation is necessary to exclude some co-incidental lesion.
If frank breakthrough bleeding occurs, this can be controlled by increasing the dose of oestrogen, or by changing to another preparation, which contains a different proportion of oestrogen to progestogen.
OTHER METHODS OF SYSTEMIC CONTRACEPTION Variable dose combined pill The so-called triphasic pills employ a varying dose of oestrogen and progestogen during the cycle with the idea of producing a more natural hormonal pattern.
The dose of oestrogen increases from 30 micrograms of ethinyloestradiol in the first 6 days of the cycle to 40 micrograms for the next 5 days, and then reverts to 30 micrograms for 10 days. The progestogen, levonorgestrel, is increased progressively from 50 to 75 to 100 micrograms in the three successive stages. Ethinyl Est. levonorgestryl 30 gm gm
Continuous oral progestogens Continuous daily administration of a small dose of one of a variety of progestogen is another method of systemic contraception. Many women find it easier to remember to take a tablet every day.
These preparations are less effective (index ) than the combined pill, and have the disadvantage that the endometrium tends to break down and bleed at irregular intervals.
during lactation They do not carry any risk of thrombo-embolism and they can be used during lactation. They act by causing increased viscosity of cervical mucus and endometrial changes.
Injectable steroids Slow-release, long acting, progestogen preparations can be given by IM injection at intervals of 1- 6 months. The best-known depot preparation is medroxyprogesterone acetate (Depot-Provera) but recently norethisterone enanthate in castor oil has also been used.
Uterine bleeding tends to be irregular, and may be heavy and prolonged. Subsequent amenorrhoea may also occur. The dose for 3- monthly injection is 150 mg and an index of 0.5 to 1.5 is claimed.
Injectable steroids can be used: 1. Following rubella vaccination in the puerperium, 2. While the male partner is waiting for vasectomy to be proved effective; 3. In women with mental retardation 4. For population control in developing countries. 5. During lactation
Postcoital contraception This term applies to methods used to prevent implantation of a fertilized egg after unprotected intercourse. They are only effective if used soon after intercourse, although the combined pill method may be used up to 4 days afterwards.
1. An initial dose of 2 tablets of a high-dose combined pill is given, followed by another similar dose 12 hours later. The failure rate is said to be 2 to 3 percent. 2. Ethinyloestradiol 5 mg daily for 5 days, starting not later than 36 hours after intercourse is more effective but causes troublesome nausea and vomiting.
3. The insertion of an intrauterine device in the first four days after unprotected intercourse is highly effective in preventing pregnancy.
SIDE EFFECTS OF SYSTEMIC CONTRACEPTIVES 1.Headache 2.Nausea 3.Facial pigmentation 4.Fluid retention and weight increase 5.Discomfort in the breasts
6.Inter-menstrual break-through bleeding 7.Increased cervical secretion (a cervical erosion may be found) 8.Depression or irritability Usually such symptoms improve after two or three cycles.
Menstrual periods are usually more regular and the loss is almost diminished. Dysmenorrhoea may be relieved. The effect on libido is variable.
Mortality There is an increased mortality in women using the pill over women not using it. This is related to age and smoking habits but not to the duration of use. Death is most often the results of pulmonary embolism or cerebral or coronary thrombosis, but hypertension may also be implicated.
Women under 35 years of age who are on the pill, but do not smoke, have virtually no excess mortality over other women. Those under 35 who are on the pill and smoke have excess mortality of about 10 per 100,000 woman years
Thrombosis Women taking the pill are more likely to be admitted to hospital with thrombo-embolic disorders than comparable groups of women who are not taking the pill and are not pregnant
The oestrogen content of the pill causes an increase in the platelet count and in platelet adhesiveness, and a decrease in antithrombins in the blood. Now that combined pills containing 30 micrograms of oestrogen are most often used, deep venous thrombosis and pulmonary embolism are rare.
Varicose veins are not Varicose veins of the leg without evidence of deep thrombosis are not contraindications to the use of the pill.
Contraindications (relative): 1. Heart disease 2. hypertension 3. Cholestasis & gall bladder disease 4. Diabetes mellitus 5. Allergic disease as asthma 6. Optic neuritis, retinal perivasculitis, glaucoma & otosclerosis 6. Mental disorders and depression 7. Migraine, epilepsy 8. Oligomenorrhoea & amenorrhoea 9. Fibroids 10. Sickle cell anaemia 11. Over 40 years 12. Smokers over 35 years
Contraindications (absolute): 1. Liver disease including hepatic adenoma 2. Existing or treated breast cancer 3. P.H. thrombosis, embolism, cardiovascular or cerebro-vascular accident 4. Optic neuritis and retinal peri-vasculitis
Thromboembolism The combined pill is usually contraindicated because of the added risk of thrombosis. Progestogen-only pills may be used as an alternative.
Hypertension Some women develop hypertension while taking the pill. The blood pressure should be checked before starting the pill, and at intervals while it is being used.
Metabolic effects Glucose tolerance is reduced by some oral contraceptives, as it is in pregnancy. Low-dose combined pills do not affect tolerance, but an increased production of insulin by the islet cells is needed to maintain normal glucose levels.
Gestational diabetics and women who have shown impaired glucose tolerance in pregnancy should avoid the combined pill as it may occasionally cause them to become established diabetics.
Hepatic function Both oestrogens and progestogens may affect hepatic function, and it is therefore unwise to give oral contraceptives to women who have a history of cholestasis of pregnancy.
Patients with abnormal liver function should not be given oral contraceptives until liver function tests have returned to normal. Any woman who develops jaundice or itching with the pill must discontinue it.
Carcinogenic effects Some investigators have suggested that there is an increased risk of breast cancer in women taking pills containing high-potency progestogens, especially before the birth of the first child. Other investigators have denied such an association.
The risk, if it exits, must be small since the incidence of breast cancer has not shown a rise in the United Kingdom. The incidence of benign disease of the breast seems to be reduced in pill users, and the same is true for carcinoma of the ovary and carcinoma of the endometrium.
The possibility of an association between long term pill usage and carcinoma of the cervix has also been discussed, but the existence of other etiological factors related to intercourse in this disease make the significance of any association hard to assess.
For the present the risk of cancer of the breast or cervix should not be taken as a contraindication to prescribing the pill as a contraceptive. All patients on the pill should have the breasts and cervix examined at regular intervals, and ideally should have an annual cervical smear.
Effect on menstruation Most women have regular, light and painless (anovulatory) periods while they are taking the combined pill, and usually ovulatory cycles return as soon as the tablets are stopped.
In a few women, “post-pill amenorrhoea” occurs, and may persist for several months. This is seen particularly in women who had irregular menstrual cycles or episodes of amenorrhoea before starting oral contraception. Most of these patients will resume regular menstruation spontaneously within 6 months.
Contraceptive steroids neither delay nor accelerate the onset of the menopause
Effect on subsequent pregnancy and on lactation Babies born to women who have taken the pill after pregnancy has started show no increase in the incidence of congenital abnormalities.
Combined oral contraceptives affect lactation in some women, reducing the volume and quality of the milk. Progestogen-only preparations, given either orally or by injection, are preferred during breastfeeding.
Surgical operations Most surgeons advise discontinuation of pills containing oestrogens for 2 months before and after surgical operations which themselves carry any risk of thrombosis.
INTERACTION BETWEEN DRUGS AND SYSTEMIC CONTRACEPTIVES Systemic contraceptive steroids may interfere with the treatment of hypertension because of their effect on the blood pressure. Some drugs affect the action of contraceptive steroids.
Anticonvulsants Breakthrough bleeding and failure of contraception may occur in patients taking phenytoin, rifampicin, griseofulvin or phenobarbitone, probably because these drugs increase the activities of hepatic enzymes, which metabolize steroids.
Antibiotics Ampicillin, amoxycillin, tetracyclines and neomycin prevent absorption of oestrogen and its reabsorption after excretion in the bile by killing bacteria in the gut that are responsible for hydrolyzing oestrogen that has been conjugated in the liver. As a result the blood oestrogen level falls and contraception may fail.
ESSENTIAL STEPS BEFORE PRESCRIBING SYSTEMIC CONTRACEPTIVES Apart from the general history and pelvic examination necessary to determine the best method for the particular patient, the blood pressure and weight are recorded, the breasts are examined and a cervical smear is taken. Observations of the blood pressure and weight are made at each successive visit.
INTRAUTERINE CONTRACEPTIVE DEVICES They are made of plastic material. Some devices are wound with fine copper wire, from which copper ions are constantly released.
Copper inhibits the enzymes concerned with implantation and development of the blastocyst and it may also be spermicidal.
Mode of action Intrauterine devices cause a mild inflammatory reaction in the endometrium, which becomes infiltrated with leucocytes and macrophages.
Insertion It should be immediately after menstruation, when the cervix is less tightly closed, or at a postnatal examination. A pelvic examination is made to exclude any possible contraindication, and to determine the position of the uterus.
Failure rate Intrauterine devices are more effective (index less than 3) than all other methods of contraception except the oral pill or sterilization. Pregnancy can occur if the device is expelled without the patient noticing or if the uterus is perforated.
Side-effects and complications Pain Colicky pain may occur for a time after insertion, particularly if the device is large. It is not usually severe.
Menstrual loss This is generally heavier and more prolonged for a few months after insertion. In some cases spotting precedes and follows the flow. Severe menorrhagia and dysmenorrhoea requiring removal of the device occur in about 8 percent of cases during the first year.
Expulsion Expulsion of the device is most likely to occur during the first year. Women should be told to feel for the rail of the device after each period to check that it is still in position.
Perforation of the uterus This accident occurs about once in 1000 first fitting; the incidence varies with the experience of the operator, and is usually due to too much force, especially if the cervical canal is narrow.
Salpingitis There is an increased incidence of pelvic inflammatory disease among women using intrauterine devices.
Endometritis All intrauterine devices induce an inflammatory reaction in the adjacent endometrium. This probably plays an important part in preventing a fertilized egg from implanting.
Pelvic infection with actinomyces organisms is an uncommon complication and is most likely with a plastic device that has been in situ for some years. The device should be removed and penicillin given.
Intrauterine pregnancy occurs with a device in place. The intrauterine device may be extruded spontaneously. Ectopic pregnancy There is no evidence that the incidence is greater than in the general population exposed to the risk of pregnancy, but if a pregnancy is suspected, ectopic pregnancy must be excluded early in the management. Pregnancy with an intrauterine device
Contraindications 1.Pelvic infection is a contraindication to the fitting of an intrauterine device; any active infection should be treated first. 2.Any cardiac lesion that carries a risk of bacterial endocarditis.