***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: The purpose of this study is to compare bleeding patterns and acceptability of a contraceptive regimen of combined 20 microg ethinyl estradiol/100 microg levonorgestrel taken with and without a hormone-free interval . Thirty-two women desiring oral contraception were r and omized to six 28-day cycles ( st and ard group ) or 168 days without a pill-free interval ( continuous group ) . Participants kept a daily bleeding calendar documenting bleeding events ( none , spotting or required sanitary protection ) and side effects ( headache , nausea , breast tenderness , depression , premenstrual syndrome and bloating ) . Primary outcome was number of bleeding days . Secondary outcomes included bleeding days requiring sanitary protection , amenorrhea , patient acceptability of bleeding patterns , method satisfaction and affective side effects . There were no differences in the baseline characteristics of the two groups . Although total bleeding days were fewer in the continuous group ( mean = 25.9 vs. 34.9 days ) , this result did not reach statistical significance . However , women in the continuous group reported significantly fewer bleeding days that required protection ( 18.4 vs. 33.8 days , p < 0.01 ) , and were more likely to have amenorrhea . Although both groups reported a high level of satisfaction with bleeding patterns and side effect profiles , women in the continuous group reported significantly fewer days of bloating ( 0.7 vs. 11.1 days , p = 0.04 ) , and menstrual pain ( 1.9 vs. 13.3 days , p < 0.01 ) . Continuous use of 20 microg ethinyl estradiol/100 microg levonorgestrel is associated with less bleeding requiring protection , and more amenorrhea than st and ard administration . Taken with or without a hormone-free interval , this oral contraceptive formulation is highly acceptable with regard to bleeding patterns and side effect profile . The continuous group had fewer light and moderate bleeding days , less bloating and menstrual pain . For patients who are seeking these results , this method may be more desirable Objective : To assess whether a low-dose oral contraceptive ( OC ) is more effective than placebo treatment for dysmenorrhea pain in adolescents . Methods : This was a r and omized , double-blind , placebo-controlled clinical trial of 76 healthy adolescents aged 19 years or younger reporting moderate or severe dysmenorrhea . Subjects were r and omly allocated to receive either an OC ( ethinyl estradiol [ E2 ] 20 & mgr;g and levonorgestrel 100 & mgr;g ) or a matching placebo for 3 months . Participants used their usual pain medications as needed during the trial . The main outcome measure was score on the Moos Menstrual Distress Question naire ( pain subscale ) for the third menstrual cycle on treatment . Secondary outcomes included pain intensity ( rated 0 to 10 ) , days of any pain , days of severe pain , hours of pain on worst day , and use of pain medications . Results : The mean Moos Menstrual Distress Question naire pain score was lower ( less pain ) in the OC group than the placebo group ( 3.1 , st and ard deviation 3.2 compared with 5.8 , st and ard deviation 4.5 , P = .004 , 95 % confidence interval for the difference between means 0.88–4.53 ) . By cycle 3 , OC users rated their worst pain as less ( mean pain rating 3.7 compared with 5.4 , P = .02 ) and used fewer pain medications than placebo users ( mean pain pills used 1.3 compared with 3.7 , P = .05 ) . By cycle 3 , OC users reported fewer days of any pain , fewer days of severe pain , and fewer hours of pain on the worst pain day than placebo users ; however , these differences did not reach statistical significance . Conclusions : Among adolescents , a low-dose oral contraceptive relieved dysmenorrhea-associated pain more effectively than placebo . Level of Evidence : 398 new users of oral contraceptives at the Research Clinic of the Southwest Foundation Texas were asked if they experienced nausea vomiting headache or breast discomfort nervousness or depression and had weight and blood pressure recorded in the pretreatment cycle and at monthly visits . Each received placebo Oracon ( sequential ) Ovulen-21 ( combination ) Norinyl-1 or .5 mg chlormadinone acetate in a double-blind protocol incorporating a pretreatment placebo cycle crossover to an active pill for 4 cycles and 2 more crossovers for Cyles 5 and 6 . The only symptoms significantly higher than in the pretreatment ( placebo ) cycle were nausea and vomiting with Oracon ( p greater than .05 ) and headache with Ovulen ( p greater than .05 ) . Pointing out that the highest incidence of complaints occurred in the placebo cycle the authors conclude that controls are necessary in contraceptive trials but the first cycle is not valid for comparison This r and omized , multicenter , parallel group study evaluated four new oral contraceptive regimens of norgestimate ( NGM ) and ethinyl estradiol ( EE ) relative to ORTHO TRI-CYCLEN ( NGM 180/215/250 microg/EE 35 microg ) . Healthy women ( 50/group ) received three cycles of either ORTHO TRI-CYCLEN Lo ( NGM 180/215/250 microg/EE 25 microg ) , one of three cyclophasic regimens ( NGM cycling 180 - 250 microg/EE 35 microg or 25 microg ) or ORTHO TRI-CYCLEN . Among all five regimens , ovulation suppression , cycle control and safety were generally comparable . Presumed ovulation ( serum progesterone levels > or=3 ng/mL during Days 19 - 21 of Cycle 3 ) , occurred in 0/41 ( 0 % ) subjects on ORTHO TRI-CYCLEN Lo and 3/43 ( 7 % ) subjects on ORTHO TRI-CYCLEN . Breakthrough bleeding and /or spotting ( BBS ; % total cycles ) was 17.2 % for ORTHO TRI-CYCLEN Lo and 14.4 % for ORTHO TRI-CYCLEN . The mean number of days of BBS/cycle for ORTHO TRI-CYCLEN Lo and ORTHO TRI-CYCLEN was 3.7 and 3.1 , respectively , for those subjects with such bleeding . Thus , ORTHO TRI-CYCLEN Lo appears similar to ORTHO TRI-CYCLEN in inhibiting ovulation and providing cycle control Efficacy , cycle control , tolerance , and adverse events were studied in a clinical Phase IV study using a new progestogen , gestodene , in an amount of 75 micrograms combined with 30 micrograms ethinylestradiol . The study was performed as a multicenter trial in 96,000 patients over a period of 6 cycles . Half of the patients taking the new preparation were first-time OC users , the other half switched from another OC . With regard to contraceptive efficacy , the life-table analysis showed a value of 0.032 % for method failure and 0.114 % for patient failure . The correspondent Pearl-Index is 0.062 and 0.22 . The new drug was found acceptable by more than 90 % of the women involved in the trial . Dysmenorrhea present in the " switchers " mostly disappeared on the new OC , while body weight and blood pressure remained virtually unchanged . Thus , it can be concluded that blood pressure and body weight behaviour is similar to that seen with other low-dose OCs . The new combined pill offers excellent cycle stability and has a very favourable effect on dysmenorrhea . The number of clinical ly diagnosed thrombotic events documented in this study was 0.65 per 1000 woman-years ( TWY ) and does not exceed the range of events seen in groups of women using non-hormonal methods of contraception ( Oxford-FPA study 0.4/TWY and RCGP study 0.8/TWY ) OBJECTIVE To compare the cycle control and tolerability of two oral contraceptives containing 20 micrograms ethinylestradiol and either 150 micrograms desogestrel or 75 micrograms gestodene . METHODS A r and omized , multicenter study was conducted in which 1016 healthy adult women received the desogestrel  ( n = 509 ) or the gestodene ( n = 507 ) preparation for six treatment cycles . RESULTS No significant differences in bleeding patterns were detected between the two treatments . The incidence and duration of irregular bleeding decreased markedly , and to a similar extent , during each treatment . The occurrence of irregular bleeding per cycle decreased from 24.6 to 9.4 % in the desogestrel group and from 19.7 to 8.6 % in the gestodene group . Its duration fell from 1.1 to 0.2 days and from 0.9 to 0.3 days , respectively . There was a consistently low incidence of amenorrhea ( 1.0 - 2.8 % ) . There were no significant differences between treatments for the incidence , intensity or emergence of dysmenorrhea . During both treatments , the incidence of premenstrual syndrome and complaints such as breast tenderness , nausea and headache dropped markedly . CONCLUSION Ultra low-dose oral contraceptives containing desogestrel or gestodene offer equivalent , good cycle control and improvements in dysmenorrhea and premenstrual syndrome and have similar , excellent tolerability profiles The contraceptive efficacy , cycle control , and safety of a new low-dose , triphasic desogestrel/ethinyl estradiol oral contraceptive ( CTR 77 , Cyclessa(TM ) ) was compared to that of a marketed , triphasic norethindrone/ethinyl estradiol oral contraceptive ( Ortho-Novum(R ) 7/7/7 ) . Two identical multicenter , open-label , r and omized , parallel group , comparative Phase III 6-cycle trials were design ed to each enroll 4200 healthy women . The combined comparative data for Cyclessa versus Ortho-Novum 7/7/7 for both studies are reported here . Cyclessa and Ortho-Novum 7/7/7 had comparable contraceptive efficacy . Despite a lower ethinyl estradiol dose ( 25 microg/day vs. 35 microg/day ) , the Cyclessa group had significantly improved cycle control in comparison to the Ortho-Novum 7/7/7 group for presence of a withdrawal bleed ( p = 0.001 ) , lack of early withdrawal bleed ( p = 0.01 ) , and breakthrough bleeding/spotting ( p = 0.001 ) . For each of the months of the study , the incidence of breakthrough bleeding/spotting was lower in the Cyclessa group than the Ortho-Novum 7/7/7 group ( breakthrough bleeding , p = 0.006 ; breakthrough spotting , p = 0.001 ) . The incidence of other adverse events was similar among treatment groups , an observation that supports the safety of both formulations . There was significantly less weight gain ( p = 0.0002 ) and less increase in the body mass index ( BMI ) ( p = 0.0002 ) in the Cyclessa group . The contraceptive efficacy and safety of Cyclessa is comparable to Ortho-Novum 7/7/7 . Cyclessa provides significantly improved cycle control with no weight gain Prostagl and in synthetase inhibitors have been used in clinical trials for the treatment of primary dysmenorrhea on the theory that the disorder may be caused by a high level of prostagl and ins . However , a causal role of prostagl and in in dysmenorrhea has not been established , and there is only indirect evidence that the amelioration of dysmenorrhea by prostagl and in synthetase inhibitors is related to their inhibition of prostagl and in synthesis in the uterus . We , therefore , monitored menstrual prostagl and in release in 14 dysmenorrheic patients in a controlled , double-blind , cross-over trial of ibuprofen ( Motrin ) and in two dysmenorrheic subjects while they were receiving oral contraceptive therapy and while they were not . A total of 89 menstrual cycles were studied . We found that ibuprofen therapy reduced menstrual prostagl and in release and relieved dysmenorrhea but that placebo therapy did not . Oral contraceptives decreased menstrual flow , reduced prostagl and in release and also alleviated dysmenorrhea . We conclude that primary dysmenorrhea is related to a high level of menstrual prostagl and in release .  Ibuprofen inhibits prostagl and in synthesis whereas oral contraceptives inhibit ovulation and cyclic endometrial development . Thus , the two drugs suppress endometrial prostagl and in through different mechanisms . Reduction of menstrual prostagl and in release leads to alleviation of dysmenorrhea OBJECTIVE This study was undertaken to compare the effects of 2 oral contraceptive regimens on menstrual cycle control and laboratory findings . METHODS In a multicenter r and omized study 100 microg levonorgestrel with 20 microg ethinyl estradiol ( Alesse or Loette ) was given to 155 healthy women . A triphasic preparation of 500 , 750 , and 1000 microg norethindrone with 35 microg ethinyl estradiol ( Ortho-Novum 7/7/7 or TriNovum ) was given to 167 women for 1 to 4 
    Output:
    
There is limited evidence for pain improvement with the use of the OCP ( both low and medium dose oestrogen ) in women with dysmenorrhoea .
There is no evidence of a difference between different OCP preparations