Oral contraceptives continuous

Composition of Commonly Prescribed Oral Contraceptives" (Continued)... 

Areas of Continued Research. Research continues in many academic and pharmaceutical laboratories throughout the wodd with the objective of improving oral contraceptives and better understanding their pharmacological and clinical actions. 

Susan Parker, a mother of three young children, calls the health clinic where you work stating that she has missed 3 days of oral contraceptives when she was ill. She wants to know if she can continue with the oral contraceptive. Discuss what information Susan needs to know to protect herself from becoming pregiant. 

Like the medical treatment of uterine leiomyomas, danazol, gestrinone, mifepristone, and GnRH-a, with or without add-back therapy, have been proposed for the treatment of endometriosis as well (Olive et al. 2001 Stones et al. 2004), but unlike leiomyomas, oral contraceptive pills, in cyclic or continuous administration, and medroxyprogesterone acetate also seem to be effective (Olive et al. 2001 Stones et al. 2004). A significant benefit in terms of pelvic pain relief also is obtained with the use of nonsteroidal anti-inflammatory drugs (Olive et al. 2001 Stones et al. 2004). 

Oral contraceptives Probable induction of cytochrome P450 metabolic pathway Reduced blood levels with risk of breakthrough bleeding Possible failure to prevent conception Weigh benefits of continuing use of SJW and possibiy reduced contraceptive effect... 

The incidence of serious known toxicities associated with the use of these drugs is low—far lower than the risks associated with pregnancy. There are a number of reversible changes in intermediary metabolism. Minor adverse effects are frequent, but most are mild and many are transient. Continuing problems may respond to simple changes in pill formulation. Although it is not often necessary to discontinue medication for these reasons, as many as one third of all patients started on oral contraception discontinue use for reasons other than a desire to become pregnant. 

There is some reason to distinguish this from the ischemia that can be caused by oral contraceptives, in that it is restricted to the colon, can have a chronic or remitting course, can present with non-specific abdominal and colonic symptoms, can be reversible despite continued use of estrogen, and does not require surgical treatment. The symptoms of intestinal ischemia resolve within days to weeks after withdrawal of the estrogen. However, oral contraceptives have also been reported to cause ischemic colitis. 

Many studies have also shown a duration-related protective effect of combined oral contraceptives on endometrial cancer, the risk before age 60 being reduced by 38% after 2 years of use and up to a 70% reduction after 12 years (114). This beneficial effect continued for at least 15 years after the end of use. As with ovarian cancer, the CASH study results suggest that the lower-dose combined oral contraceptives have a protective effect similar to that of the higher-dose tablets (115). 

A meta-analysis of epidemiological studies of ovarian cancer showed a summary estimated relative risk of 0.64 for ever-use of combined oral contraceptives, implying a 36% reduction in ovarian cancer risk (130). This protective effect increased with increasing duration of oral contraceptive use and continued for at least 10 years after discontinuation. Although most of the oral contraceptives reported in these studies were older, higher-dose formulations, the Cancer and Steroid Hormone (CASH) study included users of tablets containing ethinylestradiol 35 pg or less, and this subgroup of women had a reduced risk of ovarian cancer (115). 

A systematic review of published data on the occurrence of headache with the more modest combination products now used has shown little indication that they have a clinically important effect on headache in most women (142). Headache that occurs during early cycles of oral contraceptive use tends to improve or disappear with continued use. No clear evidence supports the common clinical practice of switching from one oral contraceptive to another in the hope of attaining a lower incidence of headache. However, manipulating the extent or duration of estrogen withdrawal during the cycle may provide benefit. 

A 40-year-old white woman with skin type II who for 4 months had been taking a low-dose combined oral contraceptive based on levonorgestrel and ethinylestradiol developed skin fragility on her sun-exposed forearms, with blisters, erosions, and scars. Histology led to a diagnosis of pseudoporphyria, since porphyrin concentrations were not raised. After the oral contraceptive was withdrawn the lesions healed slowly, despite continuing sun exposure. 

The Oxford Family Planning Association s continuing study has shown convincingly that death from all causes is more than doubled in oral contraceptive users who smoke 15 or more cigarettes daily (310). 

While the Norplant device has lost favor in some countries because of local intolerance and difficulties with removal, it continues to be widely used elsewhere. The difference in usage of Norplant between countries seems to reflect in part the degree of sophistication of users. Where, as in many western countries, low-dose oral contraceptives are very widely used and have become the standard by which users judge the acceptability of other means of contraception, the Norplant method has remained popular where expectations are somewhat lower. 

Edelman AB, Gallo Ml1, Jensen JT, et al. Continuous or extended cycle vs. cyclic use of combined oral contraceptives for contraception. Cochrane Database Syst Rev. 2005 CD004695. 

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