Download
1 / 34
340 likes | 349 Views
Progestogen-releasing intrauterine system (IUS).
E N D
The intrauterine system was developed to overcome some of the problems associated with conventional IUCDs and heavy menstrual bleeding. The progestogen-releasing intrauterine system in current use consists of a small plastic T-shaped frame carrying a Silastic sleeve loaded with 52 mg of levonorgestrel It is inserted into the
uterus and the steroid hormone is released steadily at 20 µg/day. The hormone prevents endometrial proliferation, thickens the cervical mucus and may suppress ovulation in some cycles. The frame, by inducing a sterile inflammatory reaction, may also contribute to the contraceptive effect. The system is fifed within the first seven days of the menstrual period, when the contraceptive effect is immediate. It is licensed for 5 years of use and is more than 99% effective. A
new frameless device containing progestogen has already been developed (Fibroplant-LNG) • In addition, a lower dose T-frame IUS called Femilis (Femilis Slim for nulliparae)
Specific considerations • Irregular vaginal bleeding is common initially with the IUS, and then it gradually ceases. The uterine bleeding associated with the IUS is lighter than the menstrual period experienced when using a copper IUCD, with possible amenorrhoea in the long term. The failure rates of both intrauterine methods compare favourably with female sterilization.
Postpartum considerations • The IUS and copper IUCD have no adverse effect on lactation. They can be inserted 4 weeks after vaginal birth or Caesarean section • Following miscarriage or induced termination of pregnancy, immediate insertion is safe.
Barrier methods of contraception (male and female methods) • Barrier methods of contraception prevent the sperm coming into contact with the oocyte. These methods include male and female condoms, caps and diaphragms which can be used in conjunction with spermicidal preparations to further increase their efficacy. • Some of the advantages of using condoms are that they are easily available at many outlets • and using them does not require medical intervention. They offer some protection against STIs • and cervical cancer and can be used with another method of contraception. This is often called ‘double Dutch method’. One of the main disadvantages of using barrier methods of contraception is the possible interruption to sexual intercourse, which may be off-putting for some couples.
It is good practice to ensure that anyone choosing a barrier method is also aware of emergency contraception and how to access it, should it be required.
Male condom • Some 4.4 billion couples worldwide use the male condom for contraception, with 6 billion couples using it for Human Immunodeficiency Virus (HIV) prevention. • However, there are striking geographical differences. Japan accounts for more than one- quarter of all condom users in the world, being used by 75% of the contraception-using population.
approximately 25% of all couples in the UK use condoms but this may be occasional use or in addition to other methods. There are many varieties of condoms on the market, including latex, hypoallergenic and polyurethane. Polyurethane condoms are less sensitive to heat and humidity and not affected by oil-based lubricants • Correct use of condoms is essential. Only condoms with a CE (European standard) mark should be used and the expiry date should be checked on the condom's package. Condoms should be stored away from extremes of heat, light and damp and care should be taken when handling the condom to prevent it from tearing. The condom is rolled on to the erect penis before any genital contact is made, as it is possible for some sperm to be present in the pre-ejaculate
About 1 cm of air-free space must be leh at the tip of the condom for the ejaculate, otherwise the condom may burst. Some condoms are designed with a teat end for this purpose. The penis should be withdrawn very soon aher ejaculation before it reduces in size and the condom becomes loose. The condom should be held in place during withdrawal of the erect penis so that it does not slip off. The condom should only be used once, and then disposed of in a waste
bin: it should not be flushed down the toilet. • Oil-based lubricants can damage rubber condoms but not polyurethane types. Water- based lubricants are not known to cause damage and are therefore recommended. • The efficacy of the condom if used correctly is 98% but is dependent on experience and age of the user.
-Female condom • The female condom consists of a polyurethane sheath that is inserted into the vagina (Fig. 27.6). The closed inner end is anchored in place by a polyurethane ring, while the outer edge lies flat against the vulva. It is available free from contraception clinics and may be purchased from selected chemists. Great care has to be taken to ensure that the penis is inserted inside the polyurethane sheath and not incorrectly positioned between the condom and the vaginal wall.
The efficacy depends on age and experience of the user, as with the male condom; however, the FPA (2011b) states that if it is used correctly it is 95% effective. • Diaphragm • A diaphragm consists of a thin rubber dome with a metal circumference to help maintain its shape (Fig. 27.7). A range of types and sizes are available and, in the UK, diaphragms are individually fifed at contraception clinics and some GP practices. Less than 1% of women use this method of contraception in the UK (Guillebaud and MacGregor 2013). It is not used widely in developing countries and Guillebaud and MacGregor (2013) believe • this may be due to the fact that the device requires medical fitting.
When in place, the rim of the diaphragm should lie closely against the vaginal walls and rest between the posterior fornix and the symphysis pubis. Before insertion, a spermicide should be applied. Aher insertion, the woman has to check that her cervix is covered by the diaphragm (see Fig. 27.8). In order to preserve spontaneity during sexual intercourse, the diaphragm can be inserted every evening as a matter of routine. • FIG. 27.8 The diaphragm in place. • If sexual intercourse occurs more than 3 hours aher insertion of the diaphragm, then additional spermicide is required. The diaphragm must be leh in place for at least 6 hours aher the last intercourse, to ensure any sperm cannot reach the cervix. Once • removed, the diaphragm should be washed with a mild soap, dried and inspected for any damage. A new diaphragm should be fifed annually or following a loss or gain in weight of more than 3 kg.
Efficacy depends on the age and experience of the user and the FPA (2010a) quote that it is between 92% and 96% effective if used according to their guidance. • Cultural beliefs may affect use of this method, for example in Judaism, where it is viewed as unacceptable to use any method of contraception that prevents the sperm from reaching its intended goal
Postnatal considerations • The size of diaphragm should be reassessed at the 6th week postpartum, when the vagina and pelvic floor muscles will have regained some of their tone and any tissue injury sustained from the birth will have healed.
Cervical and vault caps • Cervical and vault caps cover only the cervix, adhering to it by suction. They are made of rubber and look smaller in diameter than the diaphragm (Fig. 27.9). They require fifing at a contraception clinic. Only one cervical cap, the FemCap, is now available in the UK
Spermicidal products • Spermicidal agents have not been shown to increase efficacy of condoms and because they can cause irritation to genitalia, may in fact increase the risk of HIV transmission. Use of Nonoxinol-9 lubricated condoms is no longer generally recommended. However, current advice is still to use this spermicide with the female barrier methods – diaphragms and caps – as this has been shown to be beneficial (Guillebaud and MacGregor 2013). Up until recently, a range of spermicidal products were available for use in the UK. However, the only product now available is Gygel, a clear gel containing Nonoxinol-9. Spermicidal pessaries are no longer available in the UK. Foams and aerosols are yet to be introduced into the UK market, but may well be available in other countries
Efficacy • General teaching in the UK is that spermicidal products are not effective when used alone. • Emergency contraception • Emergency contraception is required when contraception has not been used before, or during sexual intercourse, used incorrectly or when there is perceived to have been a failure in the contraception used, e.g. a condom mishap such as breaking, tearing or coming off. There are three types of emergency contraception: • emergency hormonal contraception (EHC) • selective progesterone receptor modulator (SPRM) • copper intra-uterine contraceptive device (IUCD).
Emergency hormonal contraception (EHC) • EHC is a progestogen preparation with the brand name Levonelle which consists of one pill containing 1.5 mg of levonorgestrel and is available in many countries throughout the world. In the UK it is free from sexual health clinics, walk-in centres, some accident and emergency departments and GP practices. Many health centres and clinics provide EHC free of charge through selected pharmacies in an effort to reduce unwanted pregnancies. It can also be purchased over the counter from pharmacies. • This method works by delaying ovulation or preventing implantation of the fertilized oocyte, depending on the stage of ovulation. This method may be contraindicated if there has been more than one episode of unprotected sexual intercourse (UPSI) during the cycle, as the earlier sexual intercourse may already have resulted in a pregnancy. Very careful questioning by the practitioner needs to take place prior to supplying EHC to prevent an unfavourable outcome.
Nausea is uncommon with the progestogen-based pill but an additional pill may be required if the woman vomits within 2 hours of taking the medication. The next menstrual period may begin earlier or later than expected and it should be stressed that • contraception must be used until the next period commences. If the woman receives the EHC in a contraception clinic in the UK, she is always given an appointment to return to the clinic if menstruation does not commence on time, or is shorter or lighter than usual. If menstruation is more than 7 days late, a pregnancy test will be offered. Any unusual lower abdominal pain must be investigated as this could be a sign of an ectopic pregnancy. • The efficacy of EHC depends on how quickly the emergency contraception is commenced. If taken within 24 hours of unprotected sexual intercourse, it will prevent 95% of pregnancies. This gradually decreases to 58% by 72 hours (FPA 2011c ). There are very few contraindications to using this method but those health professionals administering Levonelle need to know about any other medication being used by the woman. Emergency hormonal contraception can be used more than once in each menstrual cycle, but it may disrupt the menstrual period pattern.
Selective progesterone receptor modulator (SPRM) • Ulipristal acetate with the brand name ellaOne is an emergency contraception that has been in use since 2009. In the UK ellaOne is free from sexual health clinics, walk-in centres, some accident and emergency departments and GP practices. It is given as a • 30 mg oral dose which should be taken as soon as possible aher UPSI or failed contraception. The action of SPRM is thought to be due to inhibition or delay in ovulation and alteration of the endometrium EllaOne is licensed for up to 120 hours following an exposure of risk to pregnancy. Only one dose of ellaOne can be taken per menstrual cycle. As with EHC, careful questioning within a consultation is required to ensure that there has been no previous risk of pregnancy either within a previous or the current menstrual cycle.
Randomized controlled trials (RCTs) have shown that ellaOne is at least as effective at preventing pregnancy as Levonelle, and pooled data demonstrate that ellaOne is more effective than EHC up to 120 hours following UPSI or failed contraception • Side-effects include abdominal pain, menstrual disorders such as irregular vaginal bleeding, disruption to the menstrual cycle with most women reporting lengthening of their cycle by 3 days; however, some women report a shortening of their cycle. Drug interactions can occur with liver enzyme-inducers such as carbemazepine and drugs that increase gastric pH, such as antacids. Ulipristal binds to progesterone receptors and therefore may reduce the efficacy of progesterone-containing contraceptives
