REVIEW ARTICLE Current Concepts in Contraception A. M. Abasiattai MBBCH, FWACS Department of Obstetrics/Gynaecology, University of Uyo Teaching Hospital, Uyo, Nigeria ABSTRACT Background: Worldwide, contraceptive use has expensive contraceptives that are easier to deliver and increased substantially over the past two decades. The cause fewer side effects than currently available increased demand for wider choices of contraceptive options4. This article thus focuses on recent methods has resulted in extensive research and developments of existing contraceptive methods and rigorous clinical trials. This has led to improvements on also reviews recently developed methods currently in existing contraceptive methods and also the use worldwide. development of several new, more effective and acceptable methods with fewer side effects. Thus, this HORMONAL METHODS article presents a review of existing literature on recent Combined Oral Contraceptives (COCs) developments on existing contraceptive methods. It These are tablets that contain a combination of also reviews recently developed contraceptive methods oestrogen and progestin and are taken daily. Though currently in use worldwide. they act primarily by suppressing ovulation, they also Methods: Relevant literature was reviewed using thicken cervical mucus thus making it impervious to manual library search, electronic sources such as CD- sperm and alter the uterine endometrium 5,6. They are ROMS and internet articles. safe, very effective when used consistently and Conclusion: More effective methods of contraception accurately with a failure rate of 0.1 in 100 pregnancies in which are generally safer and easier to administer are the first year of use 6. Currently, the development of low increasingly being developed. Hopefully, as they dose formulations has led to a reduction in the side increasingly become available in our environment, they effects of COCs including venous thrombosis and will lead to and increase in acceptance and use of myocardial infarction 6,7. Thus, most low dose pills in use contraception by our women. today contain 35micrograms (ug) or less of oestrogen and 400ug or less of progestin 7. Third generation COC KEY WORDS: Current concepts; Contraception; pills containing the progestins norgestimate, Hormonal methods; Non-hormonal methods. desogestrel and gestodene designed to reduce safety risks and side effects have also been introduced and are Paper accepted for publication 24th July 2006. now first choice oral contraceptives in most developed countries 8. These, while giving good cycle control, are INTRODUCTION less androgenic and therefore tend to be better for Contraception has been described as one of the women who have problems with acne, hirsutism and greatest advances of the twentieth century and in the weight gain; minor side effects which have been shown past two decades its use has increased substantially 9,10 12 to greatly influence compliance . COCs normalize worldwide . This has been much more striking in the menstrual bleeding, abolish primary dysmenorrhoea developing world where contraceptive prevalence rose 1 and prevent the development of pelvic inflammatory from 9% in the 1960s to 60% in 1997 . Demographic disease (PID) and benign breast disease 6,11. They also and health estimates have shown that the proportion of strongly protect against endometrial and ovarian women using modern contraceptive methods in Nigeria 2 3 cancer, with protection continuing for 10-15 years after has increased from 3% in 1990 to 8% in 2003 . Better discontinuation and with longer duration of use offering access to family planning information and services, greater protection 11. improvement in the social and economic status of women within the household and an increase in the i) Drospirenone combined oral contraceptive formal education of women has led to the increased The COC Yasmin contains 30ug of ethinyl demand for contraception and a subsequent increase in 2 estradiol and 3mg of the new progestin contraceptive use among our women . drospirenone 4. It is about as effective as other To further increase contraceptive use rates, extensive COCs in the first year of use12. In addition to research and rigorous clinical trials have resulted in preventing pregnancy, the other benefits improvements on existing contraceptive methods and drospirenone provide for some women include also the development of several more effective and less reduction in acne and hirsutism 12. Clinical trials Correspondence to: Dr. A.M. Abasiattai E-mail: [email protected] Nigerian Journal of Medicine, Vol. 15, No. 4, October - December 2006 364 Current Concepts in Contraception - A. M. Abasiattai have also found that Yasmin causes less water associated with bleeding disturbances, which have retension and thus less fluid related weight gain led to high discontinuation rates in some countries than other COCs 13. 22. Hence, new generation implants designed to make insertion and removal much easier, with more Progesterone Only Methods effectiveness and fewer complications, and with Progesterone only methods of contraception that less discomfort for users have been developed and were introduced to avoid the side effects of oestogens are now in use in the developed world. These are becoming increasing popular. All progestogen only include Jadelle (formerly known as Norplant 2); an methods act locally on the cervical mucus and the implant containing two 4 cm levonorgestrel uterine endometrium thereby preventing sperm releasing rods with effectiveness for 5 years and transport and implantation 14. Higher dose progestins Implanon; a reversible single rod containing also inhibit ovulation 14. etonogestrel effective for 3 years 8,20. Jadelle though easier to insert and remove, delivers the ii) Progesterone only injections same daily dose of LNG that Norplant delivers and These are very effective, safe, convenient for its side effects, continuation rates and most users, very easy for providers to deliver, can contraceptive effectiveness are similar to be self administered, can also be distributed easily Norplant's 23. Implanon however does not require a in non-clinical settings by non-physicians and its skin incision and releases 30-40ug of 3- administration ensures compliance 14. The two main ketodesogestrel (etonogestrel) per day 8 . This progestin only injectables are depotmedroxy hormonal level is designed to achieve complete progesterone acetate (DMPA) and norethisterone inhibition of ovulation and so far there has not been enanthate 14. DMPA, which is administered a single pregnancy reported with its use 24. intramuscularly at a dose of 150 milligrams (mg) Implanon is the only contraceptive to have a pearl every 12-calendar weeks, is far more widely used index of zero and return of fertility after removal of 8,15. It is one of the most effective methods of an implanon implant is prompt, as studies have contraception (pregnancy rate 0.3 pregnancies/ shown return of ovulation within 6 weeks 24. 100 women in the first year of use) with an efficacy equal to that of female sterilization 16. Proper iv) Desogestrel Progestin-only Contraception counselling is important before administration as These pills each contain 75ug of desogestrel, disturbances of menstruation may occur which may which are taken daily 25. Unlike other progestin only be marked and unpredictable. Also, though pills (POPs) that work primarily on the cervical reversible, there is usually a median delay in return mucus, desogestrel is unique in that it acts primarily of fertility of six months (not including the duration of by preventing ovulation and also, a pill can be taken the last injection) 8. DMPA reduces the incidence of as much as 12 hours late without reducing its endometrial and ovarian cancers, ectopic effectiveness 26. pregnancy, iron deficiency anaemia and PID 17. It is the ideal contraceptive for sicklers and epileptics as Combined Oestrogen/Progesterone Injectables it prevents sickling of cells thus reducing sickling Cyclofem, a combination of medroxy-progesterone crisis 18 and also reduces the frequency of seizures acetate (25mg) and oestradiol cypionate (5mg) and in epileptics 19. Mesigna (norethisterone 50mg and oestradiol valerate 5mg) are new injectable contraceptives that are iii) Subdermal Implants administered monthly and provide effective Norplant comprises of six 3 centimetre (cm) contraception mainly by inhibiting ovulation 27. They silastic capsules each containing 36 milligrams have been shown to have first year failure rates of 0.1- (mg) of levonorgestrel (LNG), which is inserted into 0.4/100 women years 27. Compared to progestin-only the non-dominant upper arm under local injectables, not only is there far less menstrual anaesthesia 20,21. Approximately 30ug/day of LNG is disturbance as bleeding tends to occur predictably once released and it provides excellent contraceptive a month after the first few months of use, but there is protection for 5 years (failure rate = 0.1 also an earlier return of ovulation after women pregnancies/100 women in first year of use) 8 with discontinue their use 27. Hence, women who stop using no compliance required by the user. However, it is combined injectables can become pregnant as soon as Nigerian Journal of Medicine, Vol. 15, No. 4, October - December 2006 365 Current Concepts in Contraception - A. M. Abasiattai 6 weeks after their last injection. However lack of access constant rate of drug release. Upon removal, plasma to these remains a major problem, as many women