***TASK***
the task is to simplify the input abstract of a biomedical literature

***INPUT***
the input is the abstract of a biomedical literature

***OUTPUT***
the output is the simplified abstract for the input abstract of a biomedical literature

***DOCUMENTATION***

***EXAMPLES***

Input: Only one trial of limited quality compared a biphasic and monophasic preparation. The study examined 533 user cycles of a biphasic pill (500 μg norethindrone plus 35 μg ethinyl estradiol (EE) for 10 days, followed by 1000 μg norethindrone plus 35 μg EE for 11 days; Ortho 10/11) and 481 user cycles of a monophasic contraceptive pill (1500 μg norethindrone acetate plus 30 μg EE daily; Loestrin). The study found no significant differences in intermenstrual bleeding, amenorrhea and study discontinuation due to intermenstrual bleeding between the biphasic and monophasic oral contraceptive pills. Conclusions are limited by the identification of only one trial, the methodological shortcomings of that trial, and the absence of data on accidental pregnancies. However, the trial found no important differences in bleeding patterns between the biphasic and monophasic preparations studied. Since no clear rationale exists for biphasic pills and since extensive evidence is available for monophasic pills, the latter are preferred.
Output:

We did a computer search for studies of birth control pills with two phases versus pills with one phase. We also wrote to researchers and manufacturers to find other trials. We included randomized trials in any language. We found only one trial that looked at one-phase versus two-phase birth control pills. The study authors did not report all their methods. Many of the women dropped out of the trial, and the authors did not give the reasons. The pills did not differ in any major ways, including bleeding patterns and the numbers of women who stopped using the pills. This review did not find enough evidence to say if two-phase pills worked any better than one-phase types for birth control, bleeding patterns, or staying on the pill. The one trial report had method problems and lacked data on pregnancies. Therefore, one-phase pills are the better choice, since we have much more evidence for such pills and two-phase pills have no clear reason for use.