Comparison of 400 mcg buccal and 400 mcg sublingual misoprostol after mifepristone medical abortion through 63 days' LMP: a randomized controlled trial

Combination of Mifepristone and Misoprostol for First-Trimester Medical Abortion: A Comprehensive Review of the Literature

Importance

Several medications have been used to achieve medical abortion in the first trimester of pregnancy. The most commonly used is the combination of mifepristone and misoprostol; however, different doses and routes of administration have been proposed.

Objective

The aim of this study was to summarize published data on the effectiveness, adverse effects, and acceptability of the various combinations of mifepristone and misoprostol in medical abortion protocols in the first trimester of pregnancy.

Evidence Acquisition

This was a comprehensive review, synthesizing the findings of the literature on the current use of mifepristone and misoprostol for first-trimester abortion.

Results

The combination of mifepristone and misoprostol seems to be more effective than misoprostol alone. Regarding the dosages and routes, mifepristone is administered orally, and the optimal dose is 200 mg. The route of administration of misoprostol varies; the sublingual and buccal routes are more effective; however, the vaginal route (800 μg) is associated with fewer adverse effects. Finally, the acceptability rates did not differ significantly.

Conclusions

Different schemes for first-trimester medical abortion have been described so far. Future research needs to focus on identifying the method that offers the best trade-off between efficacy and safety in first-trimester medical abortion.

Medical methods for first trimester abortion

BACKGROUND

Medical abortion became an alternative method of pregnancy termination following the development of prostaglandins and antiprogesterone in the 1970s and 1980s. Recently, synthesis inhibitors of oestrogen (such as letrozole) have also been used to enhance efficacy. The most widely researched drugs are prostaglandins (such as misoprostol, which has a strong uterotonic effect), mifepristone, mifepristone with prostaglandins, and letrozole with prostaglandins. More evidence is needed to identify the best dosage, regimen, and route of administration to optimise patient outcomes. This is an update of a review last published in 2011.

OBJECTIVES

To compare the effectiveness and side effects of different medical methods for first trimester abortion.

SEARCH METHODS

We searched CENTRAL, MEDLINE, Embase, Global Health, and LILACs on 28 February 2021. We also searched Clinicaltrials.gov and the World Health Organization's (WHO) International Clinical Trials Registry Platform, and reference lists of retrieved papers.

SELECTION CRITERIA

We considered randomised controlled trials (RCTs) that compared different medical methods for abortion before the 12th week of gestation. The primary outcome is failure to achieve complete abortion. Secondary outcomes are mortality, surgical evacuation, ongoing pregnancy at follow-up, time until passing of conceptus, blood transfusion, side effects and women's dissatisfaction with the method.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected and evaluated studies for inclusion, and assessed the risk of bias. We processed data using Review Manager 5 software. We assessed the certainty of the evidence using the GRADE approach.

MAIN RESULTS

We included 99 studies in the review (58 from the original review and 41 new studies). 1. Combined regimen mifepristone/prostaglandin Mifepristone dose: high-dose (600 mg) compared to low-dose (200 mg) mifepristone probably has similar effectiveness in achieving complete abortion (RR 1.07, 95% CI 0.87 to 1.33; I2 = 0%; 4 RCTs, 3494 women; moderate-certainty evidence). Prostaglandin dose: 800 µg misoprostol probably reduces abortion failure compared to 400 µg (RR 0.63, 95% CI 0.51 to 0.78; I2= 0%; 3 RCTs, 4424 women; moderate-certainty evidence). Prostaglandin timing: misoprostol administered on day one probably achieves more success on complete abortion than on day three (RR 1.94, 95% CI 1.05 to 3.58; 1489 women; 1 RCT; moderate-certainty evidence). Administration strategy: there may be no difference in failure of complete abortion with self-administration at home compared with hospital administration (RR 1.63, 95% CI 0.68 to 3.94; I2 = 84%; 2263 women; 4 RCTs; low-certainty evidence), but failure may be higher when administered by nurses in hospital compared to by doctors in hospital (RR 2.69, 95% CI 1.39 to 5.22; I2 = 66%; 3 RCTs, 3056 women; low-certainty evidence). Administration route: oral misoprostol probably leads to more failures than the vaginal route (RR 2.38, 95% CI 1.46 to 3.87; I2 = 39%; 3 RCTs, 1704 women; moderate-certainty evidence) and may be associated with more frequent side effects such as nausea (RR 1.14, 95% CI 1.03 to 1.26; I2 = 0%; 2 RCTs, 1380 women; low-certainty evidence) and diarrhoea (RR 1.80 95% CI 1.49 to 2.17; I2 = 0%; 2 RCTs, 1379 women). Compared with the vaginal route, complete abortion failure is probably lower with sublingual (RR 0.68, 95% CI 0.22 to 2.11; I2 = 59%; 2 RCTs, 3229 women; moderate-certainty evidence) and may be lower with buccal administration (RR 0.71, 95% CI 0.34 to 1.46; I2 = 0%; 2 RCTs, 479 women; low-certainty evidence), but sublingual or buccal routes may lead to more side effects. Women may experience more vomiting with sublingual compared to buccal administration (RR 1.33, 95% CI 1.01 to 1.77; low-certainty evidence). 2. Mifepristone alone versus combined regimen The efficacy of mifepristone alone in achieving complete abortion compared to combined mifepristone/prostaglandin up to 12 weeks is unclear (RR of failure 3.25, 95% CI 0.81 to 13.09; I2 = 83%; 3 RCTs, 273 women; very low-certainty evidence). 3. Prostaglandin alone versus combined regimen Nineteen studies compared prostaglandin alone to a combined regimen (prostaglandin combined with mifepristone, letrozole, estradiol valerate, tamoxifen, or methotrexate). Compared to any of the combination regimens, misoprostol alone may increase the risk for failure to achieve complete abortion (RR of failure 2.39, 95% CI 1.89 to 3.02; I2 = 64%; 18 RCTs, 3471 women; low-certainty evidence), and with more diarrhoea. 4. Prostaglandin alone (route of administration) Oral misoprostol alone may lead to more failures in complete abortion than the vaginal route (RR 3.68, 95% CI 1.56 to 8.71, 2 RCTs, 216 women; low-certainty evidence). Failure to achieve complete abortion may be slightly reduced with sublingual compared with vaginal (RR 0.69, 95% CI 0.37 to 1.28; I2 = 87%; 5 RCTs, 2705 women; low-certainty evidence) and oral administration (RR 0.58, 95% CI 0.11 to 2.99; I2 = 66%; 2 RCTs, 173 women). Failure to achieve complete abortion may be similar or slightly higher with sublingual administration compared to buccal administration (RR 1.11, 95% CI 0.71 to 1.74; 1 study, 401 women).

AUTHORS' CONCLUSIONS

Safe and effective medical abortion methods are available. Combined regimens (prostaglandin combined with mifepristone, letrozole, estradiol valerate, tamoxifen, or methotrexate) may be more effective than single agents (prostaglandin alone or mifepristone alone). In the combined regimen, the dose of mifepristone can probably be lowered to 200 mg without significantly decreasing effectiveness. Vaginal misoprostol is probably more effective than oral administration, and may have fewer side effects than sublingual or buccal. Some results are limited by the small numbers of participants on which they are based. Almost all studies were conducted in settings with good access to emergency services, which may limit the generalisability of these results.

Medical termination for pregnancy in early first trimester (≤ 63 days) using combination of mifepristone and misoprostol or misoprostol alone: a systematic review

Background

A wide range of drugs have been studied for first trimester medical abortion. Studies evaluating different regimens, including combination mifepristone and misoprostol and misoprostol alone regimens, show varying results related to safety, efficacy and other outcomes. Thus, the objectives of this systematic review were to compare the safety, effectiveness and acceptability of medical abortion and to compare medical with surgical methods of abortion ≤63 days of gestation.

Methods

Pubmed and EMBASE were systematically searched from database inception through January 2019 using a combination of MeSH, keywords and text words.

Randomized controlled trials on induced abortion at ≤63 days that compared different regimens of medical abortion using mifepristone and/or misoprostol and trials that compared medical with surgical methods of abortion were included.

We extracted data into a pre-designed form, calculated effect estimates, and performed meta-analyses where possible. The primary outcomes were ongoing pregnancy and successful abortion.

Results

Thirty-three studies composed of 22,275 participants were included in this review. Combined regimens using mifepristone and misoprostol had lower rates of ongoing pregnancy, higher rates of successful abortion and satisfaction compared to misoprostol only regimens. In combined regimens, misoprostol 800 μg was more effective than 400 μg. There was no significant difference in dosing intervals between mifepristone and misoprostol and routes of misoprostol administration in combination or misoprostol alone regimens. The rate of serious adverse events was generally low.

Conclusion

In this systematic review, we find that medical methods of abortion utilizing combination mifepristone and misoprostol or misoprostol alone are effective, safe and acceptable. More robust studies evaluating both the different combination and misoprostol alone regimens are needed to strengthen existing evidence as well as assess patient perspectives towards a particular regimen.

Acceptability and feasibility of 400 μg buccal misoprostol after 200 mg mifepristone for early medical abortion in Georgia

OBJECTIVES

The aim of the study was to examine the acceptability and feasibility of early medical abortion using 200 mg mifepristone and 400 μg buccal misoprostol in Georgia, outside the capital city of Tbilisi.

METHODS

A total of 622 women in four regions of western and eastern Georgia who presented for termination of pregnancy at up to 63 d of gestation were enrolled in the study. In the western regions, women took one 200 mg pill of mifepristone in the clinic and were given the option of administering 400 μg misoprostol buccally, either at the clinic or at home, 24-48 h later. In the eastern region, women were given the option to take both drugs at home. Abortion status was determined 2 weeks after mifepristone administration.

RESULTS

Ninety-five percent of participants had a successful abortion. Twenty-one percent of women in the eastern region elected to take mifepristone at home; nearly all participants in both regions (98%) chose to take misoprostol at home. Ninety-five percent of women were very satisfied or satisfied with the method, and 95% said they would prefer medical abortion for a future procedure.

CONCLUSIONS

Medical abortion with mifepristone and 400 μg buccal misoprostol is an acceptable and feasible option for women in Georgia, outside the capital city of Tbilisi.

Mifepristone With Buccal Misoprostol for Medical Abortion: A Systematic Review

OBJECTIVE

To summarize clinical outcomes and adverse effects of medical abortion regimens consisting of mifepristone followed by buccal misoprostol in pregnancies through 70 days of gestation.

DATA SOURCES

We used PubMed, ClinicalTrials.gov, and reference lists from published reports to identify relevant studies published between November 2005 and January 2015 using the search terms "mifepristone and medical abortion" and "buccal and misoprostol."

METHODS OF STUDY SELECTION

Studies were included if they presented clinical outcomes of medical abortion using mifepristone and buccal misoprostol through 70 days of gestation. Studies with duplicate data were excluded.

TABULATION, INTEGRATION, AND RESULTS

We included 20 studies with a total of 33,846 women through 70 days of gestation. We abstracted efficacy and ongoing pregnancy rates as an overall rate and by gestational age in days in reference to completed weeks (eg, 49 days or less, 50-56 days, 57-63 days, 64-70 days) and adverse effects when reported. The overall efficacy of mifepristone followed by buccal misoprostol is 96.7% (95% confidence interval [CI] 96.5-96.8%) and the continuing pregnancy rate is 0.8% (95% CI 0.7-0.9%) in approximately 33,000 pregnancies through 63 days of gestation. Only 332 women with pregnancies between 64 and 70 days of gestation are reported in the literature with an overall efficacy of 93.1% (95% CI 89.6-95.5%) and a continuing pregnancy rate of 2.9% (95% CI 1.4-5.7%). Currently available data suggest that regimens with a 24-hour time interval between mifepristone and buccal misoprostol administration are slightly less effective than those with a 24- to 48-hour interval. Rates of surgical evacuation for reasons other than ongoing pregnancy range from 1.8% to 4.2%. Severe adverse events like blood transfusion (0.03-0.6%) and hospitalization (0.04-0.9%) are uncommon.

CONCLUSION

Outpatient medical abortion regimens with mifepristone followed in 24-48 hours by buccal misoprostol are highly effective for pregnancy termination through 63 days of gestation. More data are needed to evaluate clinical outcomes with regimens containing mifepristone followed in 24 hours by buccal misoprostol and in pregnancies beyond 63 days of gestation.

Pain during medical abortion, the impact of the regimen: a neglected issue? A review

OBJECTIVES

To evaluate pain and other early adverse events associated with different regimens of medical abortion up to nine weeks of amenorrhoea.

METHODS

The literature was searched for comparative studies of medical abortion using mifepristone followed by the prostaglandin analogue misoprostol. Publications, which included pain assessment were further analysed.

RESULTS

Of the 1459 publications on medical abortion identified, only 23 comparative, prospective trials corresponded to the inclusion criteria. Patients in these studies received different dosages of mifepristone in combination with different dosages of misoprostol administered via diverse routes or at various intervals. Information on pain level was reported in 12/23 papers (52%), information regarding systematic administration of analgesics in 12/23 articles (52%) and information concerning analgesia used was available for only 10/23 studies (43%).

CONCLUSIONS

Neither pain nor its treatment are systematically reported in clinical trials of medical abortion; this shortcoming reflects a neglect of the individual pain perception. When data are mentioned, they are too inconsistent to allow for any comparison between different treatment protocols. Standardised evaluation of pain is needed and the correlation between the dosage of misoprostol and the intensity of pain must be assessed in future studies.

Efficacy and acceptability of early mifepristone-misoprostol medical abortion in Ukraine: results of two clinical trials

BACKGROUND

Abortion services are legally available in Ukraine although there are issues in quality and access. Two studies were conducted in Ukraine to expand options for women, and to determine the efficacy and acceptability of medical abortion.

STUDY DESIGN

Two open-label clinical trials were conducted at six clinics in Ukraine. Women were given 200 mg mifepristone followed after 48 hours by 400 μg oral misoprostol (Study One) and mifepristone followed after 24 hours by 400 μg sublingual misoprostol (Study Two). Follow-up visits were scheduled for two weeks after mifepristone administration to assess whether complete uterine evacuation had occurred.

RESULTS

Success rates were 97% in the first study and 98% in the second one. The vast majority of participants were satisfied or very satisfied with their abortion method (Study One: 94%; Study Two: 98%).

CONCLUSIONS

The two studies demonstrate high rates of success and acceptability of early medical abortion in Ukraine.