Dr.Álvaro Monterrosa Castro, MD
EThe main benefit of combined oral contraceptives is that they are an extremely effective, convenient method and reversible, in the prevention of unwanted pregnancy (2,11,51,70).Said contraceptive effectiveness is usually determined by the Pearl index.Which is calculated by multiplying the number of unwanted pregnancies presented by 12 times 100. And dividing everything by the number of cycles observed.
Consequently, Derman (Q-4) reports that The use of oral contraceptives prevents a large number of hospitalizations and deaths.Due to pregnancy-related complications.This author cites 1991 publications from the Alan Guttmacher Institute who found that about 1,614 x 100,000 pill users prevent hospitalization each year.Due to the beneficial effects of oral contraceptives (71).
In addition, avoiding pregnancy leads to a reduction in pregnancy-related maternal mortality.Event of special importance in developing countries.However, in them, the implementation of family planning programs must face great difficulties.
Consequently, we must fight against numerous myths that give rise to the ill-founded belief: that oral contraceptives increase the risks of disease in women.A poorly informed press has contributed to this by divulging, magnifying them, the potential risks.Leaving a distorted impression on the population that leads to reluctance to use the method (51,72,73).
First, maternal mortality is considered for African countries one in 150. Which is a serious Public Health problem.
Second, in Western Europe and the United States.Maternal mortality is considered to be 1/10,000.Despite these figures, oral contraceptives are safer than the risks inherent to pregnancy (74).
Third, for 1980 Ory and Collaborators ( 75).They calculated in the USA an annual mortality related to oral contraceptives of 3.7 x 100,000 users.(With variation from 1.8 in non-smokers to 6.5 in smokers).
In conclusion, if for the same period maternal mortality was 20.6 x 100,000 live newborns.That is, five times larger.The benefit in terms of risk of death generated by oral contraceptives (76)is deducted.
Other beneficial effects: Non-contraceptives
Since the mid-sixties a series of adverse effects.Some real or potential serious cardiovascular events were reported with the use of oral contraceptives (4).Its relationship with the estrogen dose and the type of progestogen used was soon evident.(32).
But at the same time these side effects were evident.Some beneficial effects were reported (2,3,76,77,78).Today they are well established and accepted.And they are an important way to improve maternal morbidity and mortality attributable to pregnancy and childbirth.Ectopic pregnancy and voluntary termination of pregnancy (3,11,73,79).As well as offering advantages for women’s health (20,38,70,77, 80).
However, only a relatively small amount of this information has been disclosed (51).By 1982, Ory estimated that 50,000 hospitalizations were avoided each year.Among previous and current users of combined oral contraceptives in the USA exclusively (77).
In addition, many of the non-contraceptive benefits of combined oral contraceptives are unknown to the population. majority of doctors (51.73).Many of these studies, where non-contraceptive beneficial effects are demonstrated, were carried out with macrodoses (9).And there is no evidence whether these effects have been reduced or disappeared with the use of microdoses or with third-generation progestogens.
Finally, most of the non-contraceptive beneficial effects are a consequence of the suppression of ovulation (71).Table No. 3 presents a list of these benefits.Some with more evidence than others and a few under discussion (51.76).
Table N° 3: Benefits of Oral Contraceptives
Drife J.Improvement of Dysmenorrhea
Oral contraceptives are very effective in managing dysmenorrhea.In the old and now classic study of oral contraceptives carried out by the Royal Collage of General Practitioners(80).It was found that dysmenorrhea was 63% less frequent among oral contraceptive users than among non-users (49,80).
2.Correction of irregular menstrual cycles
Combined oral contraceptives by inducing balanced hormonal levels.They stabilize changes in the endometrial tissue, reducing the incidence of menorrhagia and related disorders (81).
In addition, menstrual cycles are usually regular.Menstrual discharge occurs during periods of pause in taking the pill.
Likewise, Spotting and intermenstrual bleeding due to leakage are rare effects.Which are related to the low hormonal levels present in oral contraceptive tablets.And they generally only occur in the first cycles of pill use.Gestodeneseems to establish better cycle control than Norgestimate and Desogestrel (38.64).
3.Prevention of functional ovarian cysts
Functional ovarian cysts occur very frequently in women who ovulate.When combined oral contraceptives are administered and hormonal levels are stabilized.There is an inhibitory effect on ovarian activity.Leading to a decrease in the incidence of the formation of functional ovarian cysts.Including follicular, granulosa-lutein and thecalutein (76.82).
Consequently, this reduction in risk is only while using the pill.In the Oxford/FDA study, a 49% decrease in the incidence of follicular cysts could be observed.And a 78% decrease in the incidence of persistent corpus luteum, compared to non-user patients (83).
In 1982 Ory (77)estimated that oral contraceptives prevented 35% of hospitalizations with functional ovarian cysts.
Additionally, in 1987 Caillouette and Koehler (84)suggested that multiphasic oral contraceptives could increase the risk of functional ovarian cysts.But the Food and Drug Administration (FDA) (85)considered that the evidence was insufficient for such a relationship.And in contrast, it presented less than 40 reports of functional cysts in women who received more than 56 million cycles of multiphasic preparations between 1982 and 1986. Epidemiological studies are carried out to have greater precision (29,82,85).
4.Protection against ovarian epithelial cancer
Due to the lack of effective strategies for the early diagnosis and treatment of ovarian cancer.Prevention (76)is of capital importance.This pathology is an important cause of morbidity and mortality.
First, it was estimated that by 1980, 137,600 new cases occurred in the world (86).Large-scale studies conducted by the US Center for Disease Control and the UK Royal College of General Practitioners (RCGP).They indicate that the suppression of ovulation caused by oral contraceptives protects against the development of ovarian epithelial cancer(20.76).
Second, this beneficial effect is directly proportional to the use time.And it persists many years after planning with this method is suspended(87).The North American evaluation called: Cancer and Hormone Study (CASH).It demonstrated that the use of oral anovulatory drugs for one to five years reduces the risk of ovarian cancer by 50 to 70% (88).
In addition, this protective effect increases between longer than the time of use and extends to at least ten years after discontinuation (70.89).The World Health Organization also conducted a multicenter study confirming the protective effect of oral contraceptives against epithelial ovarian cancer(90).
Two cohort studies conducted in Great Britain Brittany.They confirmed the protective effect of the pill by finding relative risks of 0.3 and o.6 in women who had used the method at some point (83.91).
Consequently , the protective effect is both for malignant tumors and for Bordenline (92)and each of the main histological subtypes of epithelial cancer (70,93).The lower risk of epithelial ovarian cancer is both in young women and in other ages (94).Both in nulliparas and in those who have had one or more children(70).
Finally, results from the study of cancer and steroid hormones suggest that the protective effect does not depend on the dose of estrogen or progestogen.Although new evaluations are needed using microdoses and especially the new triphasic preparations (70-88).
and therefore, there is no protection against non-epithelial ovarian cancer.In the study on cancer and hormones(88).The relative risk of ovarian germ cell cancer in women who had ever used oral contraceptives was 1.6 and 1.0 in those who had used oral contraceptives for five or more years (70,88).
No relationship has been reported between the use of oral contraceptives and the risk of Benign Ovarian Teratoma.In the study carried out in Walnut Creek (95)in the USA, nor in that of the Planned Parenthood Association carried out in Oxford in the United Kingdom (83).
Finally, no relationship has been found between the use of oral contraceptives and the risk of ovarian cystadenoma (83.95).However, the British evaluation(83)suggests that the risk of ovarian cystadenoma may be lower for patients who have recently received oral contraceptives.That for old users or those who have never received them.
5.Mittelschmerz improvement
The pill usually eliminates the cramping that occurs during ovulation (19).
6 .Protection against endometrial cancer
There are several histological types of endometrial carcinoma, of which the most common is adenocarcinoma.In 1980, it was estimated that 149,000 new cases of endometrial carcinoma occurred in the world (86).The incidence rate of neoplasia increases after forty years of age.Being considered risk factors: obesity, hyperglycemia, high blood pressure, chronic anovulation.Polycystic ovary syndrome, nulliparity, early menarche and late menopause (70).
Consequently, a relationship has been observed between endometrial cancer and endogenous estrogen stimulation, when there is an inadequate cyclic exposure of progesterone (70.96).
In addition, exogenous estrogens have been observed to increase the risk of endometrial cancer in: postmenopausal women treated with estrogens without the administration of cyclic progestin.Girls with ovarian dysgenesis treated during puberty with estrogen alone.And women who received sequential oral contraceptives.Where the pharmacological preparation included many estrogen-only tablets(70.97).
A group of experts brought together in 1992 by the World Health Organization (70 ).Reviewed 11 case-control studies and 3 cohort studies.Observing a protective effect of combined oral contraceptives against endometrial cancer.
The Cancer and Hormones Study (CASH) (98)showed that with only one year The use of combined oral contraceptives reduced the risk of endometrial cancer by half.And the protective effect remained for at least 15 years.They assert that both high-dose and reduced-dose pills have a protective effect (49.98).
Likewise, some evidence shows that the protective effect emerges quite soon after from the beginning of the method (70).Another joint analysis of data from several case-control and cohort studies (97).It showed a significant trend toward decreased risk of endometrial cancer with increasing duration of oral contraceptive use.
Therefore, the risk reduction was estimated.At one year 23%, at 2 years 38%, at 4 years 51%, at 8 years 64% and at 12 years 70%.Combined oral contraceptives reduce the risk of endometrial cancer (20,71,87,99).
7.Protection against benign breast tumors
The breasts can be affected by pathologies that consist of benign proliferation.Conditions that must be studied both clinically and by pathology, to differentiate them from breast cancer.There are a variety of classifications of benign breast disease.
First, the most common condition is called fibro-cystic mastopathy.Although many other terms are used.It is characterized by proliferation and regression of breast tissues with abnormal interrelation of the epithelium with the connective tissue (70,100).
The second most frequent pathology belonging to benign breast disease is fibroadenoma.Benign breast disease is a frequent cause of consultation and a great producer of anxiety, since affected women usually believe they have cancer(70).
In addition, the maximum rate of appearance of fibroadenoma is between 20 and 39 years and that of fibro-cystic mastopathy is between 40 and 50 years(101).It has been asserted that microdose oral contraceptives are related to a lower incidence of cystic fibrosis of the breast and breast fibroadenoma.Benign conditions that, as has been said, should not be confused with breast carcinoma.
In this regard, the group brought together by the World Health Organization (70)analyzed 15 studies of cases – controls and 3 of cohorts.Most of them made in the seventies.Where it is observed that oral contraceptives have a protective effect and reduce the risk of benign breast disease by 25% (102).
Consequently, said protection is increasingly higher the longer the duration of pill use.And it is related to the progestin content.There is greater protection the higher the hormonal potency (70).
Finally, given that the components and doses of combined oral contraceptives have changed over time and they keep changing.It would be unlikely that results from previous studies could be applied to formulas from modern times.Therefore, it is necessary to investigate the potency of the different classes of estrogens and progestogens.As well as its effects on the mammary gland (70).
8.Protection against pelvic inflammatory disease
Pelvic inflammatory disease (PID) usually causes sequelae: infertility, increased rate of ectopic pregnancy and chronic pelvic pain(11).An RCGP study showed that the relative risk of PID among oral contraceptive users is half that among non-users(76.20).
Since 1980 Senanayake and Kramen (103)analyzing 7 studies had asserted the same conclusion.This protective effect is likely due to the thickening of cervical mucus produced by the hormones present in the tablet.Prevent the rise and spread of bacteria in the internal genital tract.As well as the decrease in menstrual flow.
However, the exact mechanism of the protective effect is unknown(76).Studies indicate that protection is limited to current users of oral contraceptives.And to women who have used them for at least twelve months.Protection disappearing shortly after the method was suspended(76,104).
In addition, based on figures from the Women’s Health Study (105).It is estimated that oral contraceptives prevent 50,000 initial cases of PID and 12,500 hospitalizations due to its complications each year.Wolner-Hanssem and Collaborators (106), in women with PID studied by laparoscopy.They demonstrated that oral contraceptives, in addition to reducing the frequency, reduce the severity of pelvic inflammatory involvement.
The proportion of protection against Gonococcal and non-Gonococcal PID is not specified (76).In 1985, Washington and Collaborators (107)cite studies suggesting that oral contraceptive users have a double or triple risk of Chlamydea Trachomatis infection in the lower third of the genital tract.
Consequently, this event would be related to the possibility that oral contraceptive users were more sexually active than non-users.Or a deviation produced by the greater detection in women with cervical ectropion.Which is related to the use of oral contraceptives.
Finally, the apparent greater risk of infection of the lower genital third by Chlamydea Trachomatis in users of oral contraceptives (81)requires more studies.Especially since the increased risk of cervicitis does not seem to be related to the risk of upper genital tract infection.EPI (20,71,76,108).
(Read Also: Effects of Oral Contraceptives on the Body)
9.Decrease in the incidence of ectopic pregnancy
Ectopic pregnancy can be a consequence of previous Pelvic Inflammatory Disease.It is considered that one, two, three or more episodes of PID may be related to an ectopic pregnancy rate in future pregnancies of 4, 11 and 20% respectively (11).
First, the use of oral contraceptives reduces the risk of ectopic pregnancy by more than 90%.This is because combined oral contraceptives are very effective in preventing pregnancy, mainly by inhibiting ovulation (76).The fewer eggs that are available to be fertilized, the lower the chance of pregnancy and the lower the chance of ectopic pregnancy.
In addition, the Oxford Family Planning Association (FPA) study.It did not find any cases of ectopic pregnancy among users of combined oral contraceptives.Compared to an incidence of 6.9% among users of the Intrauterine Device (81).The protective effect seems to be limited to the time of use of the oral contraceptive (76).
Finally, Mol et al (110)recently conducted a meta-analysis -analysis to evaluate the risk of ectopic pregnancy caused by various family planning methods.And they confirm that oral contraceptives have a protective effect against ectopic pregnancy.
10.Prevention of iron deficiency anemia
Combined oral contraceptives would probably cause an increase in iron stores (111).Since they cause a decrease in the amount of menstruation.They produce regularization of menstrual cycles.And they reduce the incidence of menorrhagia.
Therefore, there is less menstrual blood loss with the consequent prevention of iron deficiency anemia (20).Great value benefit.Especially for women in developing countries where iron deficiency anemia is common due to low nutritional intake (111).The effect applies to both current and past users(76).
In addition, in 1982 Ory (77)calculated that the use of oral contraceptives It prevented almost 320 cases of iron deficiency anemia per 100,000 users per year in the US.Even in patients with uterine myomatosis who receive oral contraceptives.A decrease in the duration of days of menstrual flow and an increase in hematocrit has been observed(66).
11.Lower incidence of rheumatoid arthritis
Studies conducted in Great Britain and Holland in the late 1970s.They reported that oral contraceptives were related to a 40 to 50% decrease in the incidence of Rheumatoid Arthritis (76).
Likewise, subsequent studies (112,113) indicated an absence of protective effect.Since then, it has been strongly debated whether combined oral contraceptives exert a protective effect against Rheumatoid Arthritis.
Spector and Hochberg (114)conducted a meta-analysis of 12 studies.And they conclude that oral contraceptives have not been shown to protect against Rheumatoid Arthritis.But it is very likely that they modify or delay its evolution.
12.Lower incidence of postmenopausal osteoporosis
In 1986, Lindsay and colleagues (115)suggested that the use of combined oral contraceptives increased vertebral bone density in young women .At a rate of 1% per year of use, without an increase in peripheral bone mass.
Polatti and Col (116)assert that this result is due to the fact that the pills then used contained more than 30 ugs of Ethinyl-Estradiol.They cite Shargil who reported that the administration of a triphasic oral contraceptive.(Ethynyl-Estradiol: 30-40-30 + Levonorgestrel 0.05-0.07-0.12) for more than three years in perimenopausal women.It prevented 6% of the loss of bone density observed in untreated women.
More recently, however, the same researchers (116)demonstrate that the administration of oral contraceptives that They contain Ethinyl-Estradiol 20 ug + Desogestrel 150 mg for 5 years to young women.It does not modify the vertebral bone mineral content, when evaluating urinary OH-proline excretion and bone mass density.
In addition, Beck Jr. (87)cites the study by Kritz-Silverstein (117).Who found in 239 post-menopausal women aged between 55 and 69 years.Who had used the pill for 6 or more years.A significant increase in bone density in the spine compared to women who were never users of the pill.
However, the use of oral contraceptives to prevent osteoporosis remains controversial ( 87).New studies are necessary to clarify the effect of oral contraceptives on bone mineral content (116).
13.Improvement of premenstrual syndrome
Premenstrual syndrome that occurs 7 to 10 days before the start of the period.And it affects a considerable number of women during their fertile age.It is less common among oral contraceptive users than among non-users.
14.Prevention of uterine fibroids
Uterine fibroids are benign tumors that form from the myometrium.They are common, reach very different sizes and are a frequent cause of hospitalization (70).The high peaks of normally circulating endogenous estrogens during the menstrual cycle.They act on the receptors in the myometrium and are considered to be factors related to the formation of uterine fibroids.
Likewise, these high levels of endogenous estrogens could be avoided with the simultaneous use of estrogen and synthetic gestagen.Present in microdose combined oral contraceptives.Which would reduce the incidence of uterine fibroids by 17% for every five years of use(118, 119).Therefore, the protective effect seems to be limited to the time of use of the method (70).
In addition, in the study carried out by the Family Planning Association in Oxford and published by Ross et al (118).The analysis of 535 women with fibroids revealed a decreasing risk trend.Compared with the risk for women who had never used oral contraceptives.
Consequently, the relative risk of fibroids related to the period of use, determined in the study was: 1 to 24 months 1.04 .25 to 48 months 0.80.46 to 96 months 0.79.97 to 144 months 0.73.145 and more months 0.54.P=0.015 in the linear trend of the logistic model (70,118).Contraceptives are not indicated in the medical treatment of uterine myomatosis.
Finally, Friedman and Thomas(66)in women with uterine myomatosis.They observed that microdose oral contraceptives do not produce significant changes.– neither increase nor decrease -, in uterine size.When evaluating them by clinical examination and ultrasound.They note having observed a decrease in the duration of menstrual flow and an increase in hematocrit(66).
15.Acne improvement
Combined oral contraceptives containing Gestodene, Desogestrel and especially Norgestimate.They increase the concentration of Sex Hormone Binding Globulin (SHBG) in the serum.Therefore they reduce free testosterone (6).Producing an antiandrogenic effect, which clinically translates into an improvement in acne (64).
Norgestimate does not have androgenic properties (40).Because Levonorgestrel has a relatively high androgenic activity, it will not have a protective effect.And on the contrary, it would very occasionally be associated with acne and hirsutism (62).
.
