Ulipristal acetate versus levonorgestrel for emergency contraception: a randomised non-inferiority trial and meta-analysis. Progesterone receptor modulator for emergency contraception: a randomized controlled trial. A comparison of high-dose estrogens versus low-dose ethinylestradiol and norgestrel combination in postcoital interception: a study in 493 women. Comparison of Yuzpe regimen, danazol, and mifepristone (RU486) in oral postcoital contraception. Low dose mifepristone and two regimens of levonorgestrel for emergency contraception: a WHO multicentre randomised trial. Side effects of danazol compared with an ethinyloestradiol/norgestrel combination when used for postcoital contraception. A randomized trial to compare 24 h versus 12 h double dose regimen of levonorgestrel for emergency contraception. [Emergency contraception with mifepristone and anordrin]. Randomised controlled trial of levonorgestrel versus the Yuzpe regimen of combined oral contraceptives for emergency contraception. Task Force on Postovulatory Methods of Fertility Regulation. Comparison of three single doses of mifepristone as emergency contraception: a randomised trial. Task Force on Postovulatory Methods of Fertility Regulation. A randomised study comparing a low dose of mifepristone and the Yuzpe regimen for emergency contraception. A randomized double-blind comparison of two single doses of mifepristone for emergency contraception. Comparative evaluation of the effectiveness and safety of two regimens of levonorgestrel for emergency contraception in Nigerians. Mifepristone (RU 486) compared with high-dose estrogen and progestogen for emergency postcoital contraception. A prospective randomized comparison of levonorgestrel with the Yuzpe regimen in post-coital contraception. Gestrinone compared with mifepristone for emergency contraception: a randomized controlled trial. A randomized, double-blind, noninferiority study to compare two regimens of levonorgestrel for emergency contraception in Nigeria. Modifying the Yuzpe regimen of emergency contraception: a multicenter randomized controlled trial. A randomized comparative study on mifepristone alone and in combination with tamoxifen for emergency contraception. Assessment of two emergency contraceptive regimens in Iran: levonorgestrel versus the Yuzpe.
Emergency contraception can prevent unintended pregnancies, but current methods are only effective if used as soon as possible after sexual intercourse and before ovulation. We compared the efficacy and safety of ulipristal acetate with levonorgestrel for emergency contraception.
                Women with regular menstrual cycles who presented to a participating family planning clinic requesting emergency contraception within 5 days of unprotected sexual intercourse were eligible for enrolment in this randomised, multicentre, non-inferiority trial. 2221 women were randomly assigned to receive a single, supervised dose of 30 mg ulipristal acetate (n=1104) or 1.5 mg levonorgestrel (n=1117) orally. Allocation was by block randomisation stratified by centre and time from unprotected sexual intercourse to treatment, with allocation concealment by identical opaque boxes labelled with a unique treatment number. Participants were masked to treatment assignment whereas investigators were not. Follow-up was done 5-7 days after expected onset of next menses. The primary endpoint was pregnancy rate in women who received emergency contraception within 72 h of unprotected sexual intercourse, with a non-inferiority margin of 1% point difference between groups (limit of 1.6 for odds ratio). Analysis was done on the efficacy-evaluable population, which excluded women lost to follow-up, those aged over 35 years, women with unknown follow-up pregnancy status, and those who had re-enrolled in the study. Additionally, we undertook a meta-analysis of our trial and an earlier study to assess the efficacy of ulipristal acetate compared with levonorgestrel. This trial is registered with ClinicalTrials.gov, number NCT00551616.
                In the efficacy-evaluable population, 1696 women received emergency contraception within 72 h of sexual intercourse (ulipristal acetate, n=844; levonorgestrel, n=852). There were 15 pregnancies in the ulipristal acetate group (1.8%, 95% CI 1.0-3.0) and 22 in the levonorgestrel group (2.6%, 1.7-3.9; odds ratio [OR] 0.68, 95% CI 0.35-1.31). In 203 women who received emergency contraception between 72 h and 120 h after sexual intercourse, there were three pregnancies, all of which were in the levonorgestrel group. The most frequent adverse event was headache (ulipristal acetate, 213 events [19.3%] in 1104 women; levonorgestrel, 211 events [18.9%] in 1117 women). Two serious adverse events were judged possibly related to use of emergency contraception; a case of dizziness in the ulipristal acetate group and a molar pregnancy in the levonorgestrel group. In the meta-analysis (0-72 h), there were 22 (1.4%) pregnancies in 1617 women in the ulipristal acetate group and 35 (2.2%) in 1625 women in the levonorgestrel group (OR 0.58, 0.33-0.99; p=0.046).
                Ulipristal acetate provides women and health-care providers with an effective alternative for emergency contraception that can be used up to 5 days after unprotected sexual intercourse.
                HRA Pharma.
                Copyright 2010 Elsevier Ltd. All rights reserved. Compare the efficacy and adverse effects of CDB-2914, a new progesterone receptor modulator, to levonorgestrel for emergency contraception.
                We performed a randomized, double-blinded noninferiority trial, enrolling healthy women seeking emergency contraception within 72 hours of unprotected intercourse. Participants were randomly assigned to receive a single dose of 50 mg of CDB-2914, plus a placebo 12 hours later or two doses of 0.75 mg of levonorgestrel taken 12 hours apart. Follow-up was scheduled 5 to 7 days after the expected onset of the next menstrual period. Posttreatment pregnancy was established by a positive urine test at follow-up and confirmed by quantitative serum beta-hCG. Daily diaries were used from the time of emergency contraception use until next menses to record adverse effects and sexual activity.
                Product efficacy was evaluable in 775 of CDB-2914 users and 774 of levonorgestrel users. Pregnancies occurred in 7 (0.9%, 95% confidence interval 0.2-1.6%) and 13 (1.7%, 95% confidence interval 0.8-2.6%) women, respectively. Based on the estimated cycle day of unprotected intercourse, 85% and 69% of anticipated pregnancies, respectively, were averted. Nausea was reported by a somewhat greater percentage of CDB-2914 than levonorgestrel users (29% compared with 24%, P=.03), but the distribution of other adverse effects was similar in both groups. Women in both groups experienced considerable variation in menstrual cycle length as compared with their reported individual normal cycle lengths.
                CDB-2914 is at least as effective as levonorgestrel in preventing pregnancies after unprotected intercourse and has a similar side effect profile.
                I. Ethinylestradiol (EE), at a dosage of 5 mg/day for 5 consecutive days (5 mg EE), has generally been used for interception. A combination of 200 micrograms EE and 2 mg dl-norgestrel (EE + NG) was proposed as an effective alternative. Efficacy and tolerance of these methods were compared in a randomized, double-blind study. A group of 465 women was studied with a follow-up rate of 94.3%. In the 5 mg EE group a pregnancy rate of 0.9% was observed, and in the EE + NG group a rate of 0.4% was found. These rates differ significantly from the expected rates (P less than 0.0005, in both series). Nausea was noted in 59.1% of the 5 mg EE group and in 54.0% of the EE + NG series. Nausea and vomiting occurred in 20.8% and 15.8%, respectively. The efficacy of both methods as alternative morning-after medication was confirmed. The new method is preferable because treatment is limited to only 1 day. To compare the effectiveness and acceptability of three regimens of postcoital contraception.
                Randomised group comparison of ethinyloestradiol 100 micrograms plus levonorgestrel 500 micrograms repeated after 12 hours (Yuzpe method); danazol 600 mg repeated after 12 hours; and mifepristone 600 mg single dose.
                Community family planning clinic.
                616 consecutive women with regular cycles aged 16 to 45 years.
                Number of pregnancies, incidence of side effects, and timing of next period.
                The raw pregnancy rates (with 95% confidence intervals) for the Yuzpe, danazol, and mifepristone groups were 2.62% (0.86% to 6.00%), 4.66% (2.15% to 8.67%), and 0% (0% to 1.87%) respectively. Overall, these rates differed significantly (chi 2 = 8.988, df = 2; p = 0.011). The differences between the mifepristone and Yuzpe groups and between the mifepristone and danazol groups were also significant. Side effects were more common and more severe in the Yuzpe group (133 women (70%)) than in either the danazol group (58 (30%)) or the mifepristone group (72 (37%)). The Yuzpe regimen tended to induce bleeding early but mifepristone prolonged the cycle. Three women bled more than seven days late in the Yuzpe group compared with 49 in the mifepristone group.
                Mifepristone was effective in reducing expected pregnancy rates and the Yuzpe method also had a clinical effect. Danazol had little or no effect. A further multicentre trial is needed. A single 10 mg dose of mifepristone, and two 0.75 mg doses of levonorgestrel 12 h apart, are effective for emergency contraception. Because no studies had compared the efficacies of both compounds, or investigated a single dose of 1.5 mg levonorgestrel, we undertook this three-arm trial.
                We did a randomised, double-blind trial in 15 family-planning clinics in 10 countries. We randomly assigned 4136 healthy women with regular menstrual cycles, who requested emergency contraception within 120 h of one unprotected coitus, to one of three regimens: 10 mg single-dose mifepristone; 1.5 mg single-dose levonorgestrel; or two doses of 0.75 mg levonorgestrel given 12 h apart. The primary outcome was unintended pregnancy; other outcomes were side-effects and timing of next menstruation. Analysis was by intention to treat, but we did exclude some patients from the final analyses.
                Of 4071 women with known outcome, pregnancy rates were 1.5% (21/1359) in those given mifepristone, 1.5% (20/1356) in those assigned single-dose levonorgestrel, and 1.8% (24/1356) in women assigned two-dose levonorgestrel. These proportions did not differ significantly (p=0.83). The relative risk of pregnancy for single-dose levonorgestrel compared with two-dose levonorgestrel was 0.83 (95% CI 0.46-1.50), and that for levonorgestrel (the two regimens combined) compared with mifepristone, 1.05 (0.63-1.76). Side-effects were mild and did not differ greatly between groups, and most women menstruated within 2 days of the expected date. Women who took levonorgestrel had earlier menses than did those who took mifepristone.
                The three regimens studied are very efficacious for emergency contraception and prevent a high proportion of pregnancies if taken within 5 days of unprotected coitus. Mifepristone and levonorgestrel do not differ in efficacy. A 1.5 mg single levonorgestrel dose can substitute two 0.75 mg doses 12 h apart. A postcoital contraceptive with a lower incidence of nausea and vomiting than oestrogen-progestogen combinations would be a significant advance. During a nine-month period, 101 women were treated at the Margaret Pyke Centre in London with either an oestrogen-progestogen combination or with danazol. A comparison of the side effects of each drug is reported. Those treated with danazol were six times less likely to experience nausea and none vomited. With the exception of breast symptoms, other side effects were five times less common in women receiving danazol. These differences give danazol a clear advantage in terms of patient acceptability. Further experience will enable the efficacy of danazol to be evaluated and so determine whether this drug should become the preferred hormonal postcoital treatment. Levonorgestrel (0.75 mg given for two doses 12 h apart) has been proven to be an effective regimen for emergency contraception when the first dose is given within 72 h of unprotected coitus. However, the dosing interval is inconvenient for those taking the first dose in the afternoon. We conducted a randomized study to evaluate two levonorgestrel dosing regimens for emergency contraception. Two doses of levonorgestrel 0.75 mg were administered with the first dose given up to 120 h after unprotected intercourse. The second dose was given 12 h later in the first regimen and 24 h later in the second regimen.
                We conducted a double-blind, randomized trial between 1997 and 2003 at five centres in China. A total of 2071 women requesting emergency contraception within 120 h of unprotected intercourse were recruited. They were randomized to receive two doses of 0.75 mg of levonorgestrel, given either 24 h apart or 12 h apart.
                Outcome was unknown for 53 women (24 in the 24 h group and 29 in the 12 h group). Among the remaining 2018 women, the crude pregnancy rate was 1.9% in the 24 h group [95% confidence interval (CI) 1.17-2.94] and 2.0% in the 12 h group (95% CI 1.19-2.99). The proportion of pregnancies prevented was estimated to be 72% in the 24 h group and 75% in the 12 h group. Side-effects were mild in both groups. The efficacy of the 12 h regimen declined significantly when there were further acts of intercourse after treatment (5.0 versus 1.0%, P<0.01). This was not observed in the 24 h group.
                Two doses of 0.75 mg levonorgestrel given either 24 or 12 h apart are effective for emergency contraception up to 120 h after unprotected intercourse. Further research to investigative more effective methods of emergency contraception is warranted. To study the efficacy of mifepristone or with anordrin for emergency contraception.
                300 healthy women were recruited within 7.2 hours after unprotected intercourse or contraceptive failure and randomly allocated into 3 groups. Group 1 (n = 100), mifepristone 25 mg twice with 12 hours apart; group 2 (n = 99), single dose of mifepristone 25 mg; and group 3 (n = 101), mifepristone 25 mg and anordrine 7.5 mg given once.
                No pregnancy occurred in group 1, while 1 pregnancy in each group 2 and 3. The contraceptive effectiveness were 100.0%, 83.8% and 86.1% for the 3 groups respectively. The overall menstruation disturbances and side effects were low.
                Both mifepristone 50 or 25 mg were effective for emergency contraception and no synergetic effects of anordrin in combination with mifepristone was shown in this study. A previous randomised study suggested that the progestagen, levonorgestrel, given alone in two separate doses each of 0.75 mg caused nausea and vomiting in fewer women and might be more effective than the Yuzpe regimen of combined oral contraceptives for emergency contraception, although the difference was not significant. We compared these two regimens when started within 72 h of unprotected coitus.
                We enrolled in the double-blind, randomised trial 1998 women at 21 centres worldwide. Women with regular menses, not using hormonal contraception, and requesting emergency contraception after one unprotected coitus, received levonorgestrel (0.75 mg, repeated 12 h later) or the Yuzpe regimen (ethinyloestradiol 100 microg plus levonorgestrel 0.5 mg, repeated 12 h later).
                Outcome was unknown for 43 women (25 assigned levonorgestrel, 18 assigned Yuzpe regimen). Among the remaining 1955 women, the crude pregnancy rate was 1.1% (11/976) in the levonorgestrel group compared with 3.2% (31/979) in the Yuzpe regimen group. The crude relative risk of pregnancy for levonorgestrel compared with the Yuzpe regimen was 0.36 (95% CI 0.18-0.70). The proportion of pregnancies prevented (compared with the expected number without treatment) was 85% (74-93) with the levonorgestrel regimen and 57% (39-71) with the Yuzpe regimen. Nausea (23.1 vs 50.5%) and vomiting (5.6 vs 18.8%) were significantly less frequent with the levonorgestrel regimen than with the Yuzpe regimen (p<0.01). The efficacy of both treatments declined with increasing time since unprotected coitus (p=0.01).
                The levonorgestrel regimen was better tolerated and more effective than the current standard in hormonal emergency contraception. With either regimen, the earlier the treatment is given, the more effective it seems to be. Mifepristone is a highly effective and well-tolerated emergency contraceptive when given in a dose of 600 mg within 72 h of unprotected coitus. We assessed whether the same effectiveness can be achieved with lower doses of mifepristone (50 mg and 10 mg) and a longer postcoital treatment period (120 h).
                We undertook a multicentre, single-masked, randomised trial in 11 family-planning clinics in Australia, China, Finland, Georgia, the UK, and the USA. 1717 healthy women with regular menstrual cycles who requested emergency contraception within 120 h of unprotected coitus were randomly assigned to three treatment groups.
                32 women were lost to follow-up and one was pregnant before treatment. The 600 mg, 50 mg, and 10 mg groups did not differ in the proportions of pregnancies (seven [1.3%] of 559, six [1.1%] of 560, and seven [1.2%] of 565). Two pregnancies (both in the 50 mg group) were tubal. Among women without further acts of intercourse, treatment delay did not appear to influence the effectiveness. No major side-effects occurred, except a delay in the onset of next menses, significantly (p<.001) related to the mifepristone dose.
                Lowering the dose of mifepristone sixty-fold did not decrease its effectiveness as an emergency contraceptive under typical use, though a study of this size cannot exclude differences in effectiveness up to almost three-fold. Lower doses of mifepristone were associated with less disturbance of the menstrual cycle. Thus, a dose as low as 10 mg seems preferable to the 600 mg dose. To compare 100 mg mifepristone with the standard Yuzpe regimen for emergency contraception.
                Randomised controlled trial.
                Family Planning Clinic, Aberdeen.
                One thousand women seeking emergency contraception within 72 hours after an episode of unprotected sexual intercourse.
                Women were randomised to receive either 100 mg (half tablet) of mifepristone as a single dose or the Yuzpe regimen (two tablets each with 50 microg ethinyloestradiol and 0.25 mg levonorgestrel, to be repeated 12 hours later).
                Crude pregnancy rates, proportion of pregnancies prevented, side effects and patient acceptability.
                The crude pregnancy rates (95% CI) for the Yuzpe regimen and mifepristone were 3.6% (2.3-5.7) and 0.6% (0.2-1.8), respectively, with a significant difference between the two groups (RR 6.04; 95% CI 1.75-20.75). Mifepristone prevented 92% of pregnancies and the Yuzpe regimen preventing 56%. An increasing coitus to treatment interval was associated with contraceptive failure in the Yuzpe group (P = 0.03) with no association seen with mifepristone. Following administration of mifepristone 24.5% and 13.1% given the Yuzpe regimen had a delayed period (RR 2.14; 95% CI 1.46-3.15). Overall, mifepristone was better tolerated than the Yuzpe regimen with significantly fewer side effects. More women were satisfied (P < 0.0001) with mifepristone as an emergency contraceptive and would recommend it to a friend (P = 0.02).
                Mifepristone administered in a 100 mg dose is a highly effective post-coital contraceptive with high patient acceptability and fewer side effects compared with the standard Yuzpe regimen. Delay in the onset of menstruation did not decrease patient acceptability. Previous trials have shown the potential of 10 mg of mifepristone in emergency contraception. The aim of this trial was to investigate whether 10 mg of mifepristone has the same efficacy as 25 mg.
                This double-blind, randomized trial was carried out in 10 family planning institutes and hospitals in China. Women who met recruitment criteria and requested emergency contraception within 120 h of a single act of unprotected coitus were randomized using a computer-generated list to either 10 or 25 mg of mifepristone within each centre.
                Among 3052 women enrolled, the outcome was known for 3030 women, 1516 in the 10 mg group and 1514 in the 25 mg group. Seventeen pregnancies occurred in each group, giving a pregnancy rate of 1.1%. The relative risk of pregnancy for women treated with 10 mg mifepristone compared with those treated with 25 mg was 1.0 (95% CI: 0.51-1.95) and equivalence was demonstrated within a two-fold margin. Both doses prevented 85-86% of pregnancies expected to have occurred if no treatment had been given. The pregnancy rate nearly doubled if women had further acts of intercourse. Efficacy decreased with treatment delay. Side-effects were uncommon and mild.
                A dose of 10 mg of mifepristone is sufficient for emergency contraception. Earlier treatment is preferable, although the method can be used effectively for up to 5 days after intercourse. Emergency contraception was introduced in Nigeria over two decades ago, but few women have used this method even in emergency situations because of the side effects. To find an acceptable levonorgestrel regimen for emergency contraception in our community, the two-dose regimen 0.75-mg levonorgestrel 12 h apart (group A) and the single dose 1.5-mg levonorgestrel (group B) were studied in 1118 volunteers. Mild side effects such as nausea, vomiting, lower abdominal pains, menorrhagia, dizziness, headache, and breast tenderness were reported. Significantly more women in the high-dose group reported headache, breast tenderness, and heavy menstrual flow. Eleven pregnancies (1.0%) were reported (7 in group A and 4 in group B). The crude relative risk of pregnancies was similar in the two groups (RR = 0.71, 95% CI = 0.32-1.55; p > 0.05) [corrected]. On the other hand, the estimated effectiveness rate of 86.80% in group A was significantly lower than the 92.99% for group B (p < 0.05). The pregnancy rates increased with delay in starting treatment and if further acts of unprotected sexual intercourse took place after treatment. It was concluded that both regimens were effective and safe. Mifepristone (RU 486) is a synthetic steroid with potent antiprogestational and antiglucocorticoid properties that provides an effective medical method of inducing abortion in early pregnancy. Since progesterone is essential for implantation, we tested the use of mifepristone for emergency postcoital contraception.
                We studied 800 women and adolescents requesting emergency postcoital contraception who had had unprotected intercourse within the preceding 72 hours. A total of 398 women and adolescents were randomly assigned to treatment with 100 micrograms of ethinyl estradiol and 1 mg of norgestrel, each given twice 12 hours apart (standard therapy), and 402 women and adolescents were randomly assigned to receive 600 mg of mifepristone.
                None of the women and adolescents who received mifepristone became pregnant, as compared with four of those who received standard therapy; the difference in failure rates between the two regimens was not statistically significant. The number of pregnancies in each group was significantly lower than the number expected according to calculations based on the day of the cycle during which intercourse had taken place (P less than 0.001). In many subjects the stage of the cycle as calculated by menstrual history was inconsistent with measurements of plasma progesterone or urinary pregnanediol excretion. The subjects treated with mifepristone reported less nausea (40 percent vs. 60 percent) and vomiting (3 percent vs. 17 percent) on the day of treatment, as well as lower rates of other side effects, than the subjects treated with the standard regimen, but they were more likely to have a delay in the onset of the next menstrual period (42 percent vs. 13 percent).
                Mifepristone is a highly effective postcoital contraceptive agent that, if used more widely, could help reduce the number of unplanned and unwanted pregnancies. A prospective randomized study was conducted at the Family Planning Association of Hong Kong to compare the efficacy of the Yuzpe regimen and levonorgestrel (0.75 mg for two doses 12 h apart) in post-coital contraception. A total of 424 subjects were recruited into the Yuzpe group and 410 subjects into the levonorgestrel group; 77 subjects in the Yuzpe group and 79 subjects in the levonorgestrel group had further acts of intercourse during the treatment cycle. Fifteen pregnancies (3.5%) occurred in the Yuzpe group and 12 pregnancies (2.9%) in the levonorgestrel group. After excluding the patients who had further acts of intercourse, the failure rates in the Yuzpe group and the levonorgestrel group were 2.6 and 2.4% respectively. The incidence of nausea, vomiting and fatigue in the Yuzpe group was significantly higher than those in the levonorgestrel group. We conclude that levonorgestrel is an effective drug for post-coital contraception with a lower incidence of side-effects than the Yuzpe regimen. To compare the efficacy of gestrinone with that of mifepristone for emergency contraception.
                A randomized double-blind trial was conducted in five family-planning clinics in China. We randomly assigned 998 healthy women with regular menstrual cycles and negative urine pregnancy tests who were requesting emergency contraception up to 72 hours after unprotected coitus to receive single-dose 10 mg gestrinone (n=499) or 10 mg mifepristone (n=499). We monitored them to 7 days after the expected first day of their next menstrual period. The study was powered to detect a 5% failure rate between the two regimens.
                The treatment groups did not differ significantly; posttreatment pregnancy rates were 2.4% in the gestrinone group compared with 1.8% in the mifepristone group (P=.51). The majority of women menstruated the first day of expected menses, and groups did not differ regarding side effects.
                The effectiveness of 10 mg gestrinone is not significantly different from 10 mg mifepristone as an emergency contraceptive method.
                ISRCTN Register, isrctn.org, ISRCTN87842530.
                I. Unplanned pregnancies are common in Nigeria. Much of the unplanned pregnancies is due to low contraceptive prevalence and high contraceptive user failure rates. High user failure rates suggest the important role of emergency contraception to prevent unplanned pregnancy.
                Randomized, controlled, double-blind, multicenter, noninferiority trial comparing efficacy and side effects of two emergency contraceptive regimens up to 5 days after unprotected intercourse among 3022 Nigerian women: levonorgestrel administered in two doses of 0.75 mg given 12 h apart and levonorgestrel administered in a single dose of 1.5 mg.
                Efficacy was similar between the treatment groups; post-treatment pregnancy proportions were 0.57% in the two-dose regimen vs. 0.64% in the single-dose regimen (risk difference 0.07% (95% CI -0.50 to 0.64). The majority of women menstruated the first day of expected menses and the groups did not differ regarding reported side effects.
                This study shows the simplified emergency contraceptive regimen of single-dose levonorgestrel is not inferior in efficacy to the two-dose regimen among Nigerian women.
                Copyright © 2010 Elsevier Inc. All rights reserved. Emergency contraceptives can prevent unintended pregnancy after unprotected intercourse. The best-studied regimen ("Yuzpe") consists of ordinary combined oral contraceptives containing levonorgestrel and ethinyl estradiol. Women traditionally take one dose within 72 hours after unprotected intercourse, and a second dose 12 hours later. Historically, half experience nausea and a fifth vomit. The purpose of this study was to determine whether 1). women could use combined oral contraceptives other than those containing levonorgestrel and 2). eliminating the second dose improves comfort and convenience.
                Women presenting within 72 hours after unprotected intercourse were randomized to receive 1). standard two-dose Yuzpe, 2). a variant of Yuzpe substituting norethindrone for levonorgestrel, or 3). only the first dose of Yuzpe, followed 12 hours later by a placebo.
                Perfect-use failure rates were low in all groups and did not differ in a statistically significant way (standard Yuzpe 2.0% [n = 589], norethindrone-ethinyl estradiol 2.7% [n = 547], single dose of Yuzpe 2.9% [n = 546]). Typical-use failure rates were slightly higher but similarly did not differ significantly. Side effects were similar across groups, except that women taking the single dose reported half the vomiting. Taking the pills with food did not seem to reduce nausea or vomiting, and the pills were not more effective when started sooner after unprotected intercourse.
                Oral contraceptives containing norethindrone-ethinyl estradiol work approximately as well for emergency contraception as levonorgestrel-ethinyl estradiol formulations and should be offered when first-line therapies are not available. The purpose of the clinical study was to compare the efficacy and side effects of 10 mg of mifepristone alone (Group 1) and with 20 mg of tamoxifen (Group 2) for emergency contraception, especially as used within 72-120 h after coitus. Four-hundred female volunteers with one act of unprotected intercourse or contraception failure (200 cases in each group) were recruited and completed the study. There were 198 women treated < 72 h after coitus (100 in Group 1 and 98 in Group 2), whereas the remaining 202 patients were treated between 72-120 h (100 in Group 1 and 102 in Group 2). In total, four pregnancies occurred; one treated < 72 h in each group, two between 72-120 h in Group 1. Efficacy for prevention of unwanted pregnancy by Trussell method is 84% for Group 1, and 95% for Group 2, and which is not significantly different between the two groups and even subgroups. The side effects (15.5% for Group 1 and 14.5% for Group 2) and changes in menstruation were infrequent and mild in both groups. Further studies should be conducted to determine whether tamoxifen combined with mifepristone for emergency contraception is more effective as compared with mifepristone alone. The purpose of this study was to compare the efficacy and tolerability of two emergency contraception (EC) methods, levonorgestrel versus the Yuzpe.
                In a prospective, randomized, comparative study, we included 122 healthy volunteers who in the observed cycle had had only one act of unprotected intercourse within 72 h of treatment. They were randomly allocated in levonorgestrol group (n=62) and Yuzpe (n=60). The levonorgestrel regimen consisted of two pills: 0.75 mg levonorgestrel, taken twice in the 12-h interval within 72 h after unprotected intercourse. The Yuzpe method included two HD contraceptive pills taken as another regimen. Data were collected by questionnaire at first and 3 weeks later. The differences were compared with X2 & Fisher exact tests.
                There were no significant differences between two groups in any of the observed parameters. The levonorgestrel regimen was found superior to Yuzpe because it's more effectiveness (respectively 100% vs 91%, p=0.026) and fewer side effects.
                The study showed more effectiveness and safety of the levonorgestrel regimen as emergency contraception. Thus we recommend levonorgestrel as an alternative EC method instead of the Yuzpe regimen in Iran or other developing countries in order to decrease unwanted pregnancy.
Intermediate-dose mifepristone (25-50 mg) was superior to LNG and Yuzpe regimens. Mifepristone low dose (< 25 mg) may be more effective than LNG (0.75 mg two doses), but this was not conclusive. UPA may be more effective than LNG. LNG proved to be more effective than the Yuzpe regimen. The copper IUD was the most effective EC method and was the only EC method to provide ongoing contraception if left in situ.