Flexible mifepristone and misoprostol administration interval for first-trimester medical termination

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.

A comparative study of second trimester termination of pregnancy with mifepristone and misoprostol vs misoprostol alone in 50 cases

The aim: To study the efficacy and safety of combined mifepristone and misoprostol used in second-trimester abortion(≥ 12 and ≤ 20 weeks) in comparison with only vaginal misoprostol. Materials and methods: This study was a prospective comparative randomised clinical study in women attending hospitals in need of a second-trimester abortion, i.e., 12–20 weeks of pregnancy were taken up and divided as Group A – 50 women with mifeprisptone and misoprostol, Group B – 50 women with misoprostol alone Results were analysed according to age, parity, gestational age, average dose of misoprostol required for complete abortion, Induction abortion interval, completeness of abortion, side effects and mean days of hospital stay. Results: Demographic details are comparable and insignificant in the comparison. The average dose of misoprostol (mcg) required for the completeness of abortion in group A is 596±28.28 mcg, and in group B, it is 1148±160.66 mcg (p<0.001) which is statistically significant. In the present study, the induction abortion interval is significantly less in group A compared to group B, with p<0.001. In addition, 10 out of 50 patients in group A aborted within 7 hours, whereas none in group B. Mean duration of hospital stay in group A is 24 hours. In group B, it is 34.82 hours which is statistically significant with a p-value of <0.001. 12 patients in group A and 26 in group B had side effects like nausea, vomiting, fever, headache and diarrhoea. 8 % of group A and 20 % of group B had a fever. These patients were treated with antipyretics. 6 % in group A and 14 % in group B had nausea and vomiting and were treated with antiemetics. 4 % in group A and 8 % in group B had diarrhoea and were treated with antimotility drugs. 6 % in group A and 10 % in group B had a headache; these patients were treated with NSAIDs. Conclusions: The combination of mifepristone and misoprostol is a highly effective and safe method for second-trimester termination of pregnancy. The amount of misoprostol needed to accomplish the abortion, and the severity of the adverse effects are lower in the mifepristone-primed group than in the misoprostol-alone group. Since there are fewer difficulties, this approach can be employed in hospitals with high patient density.

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.

Same-day mifepristone prior to second-trimester induction termination with misoprostol: A retrospective cohort study

OBJECTIVE

To evaluate whether same-day administration of mifepristone and misoprostol, compared with misoprostol alone, reduces the duration of second-trimester induction of labor for termination of pregnancy or increases the rate of fetal expulsion within 24 hours.

STUDY DESIGN

We conducted a retrospective analysis of patients undergoing induction of labor for pregnancy termination in the second trimester between 2009 and 2018. We compared patients who received mifepristone on the same day as the first dose of misoprostol to those who received misoprostol alone. The primary outcome was expulsion within 24 hours after the first dose of misoprostol.

RESULTS

Two hundred ninety-eight patients met criteria for inclusion, of whom 94 (31.5%) received same-day mifepristone. Expulsion within 24 hours occurred in 93.6% of the mifepristone-plus-misoprostol group and 79.9% of the misoprostol-only group (RR 1.17, 95%CI 1.07-1.28). Expulsion within 12 hours occurred in 56.4% of the mifepristone-plus-misoprostol group and 34.0% of the misoprostol-only group (RR 1.66, 95%CI 1.28-2.16). After adjusting for demographic and clinical characteristics, the rate of expulsion within 24 hours was similar between groups (RR 1.07, 95%CI 0.92-1.26), while the rate of expulsion within 12 hours remained different (RR 1.69, 95%CI 1.01-2.83). Median time to expulsion was shorter in the mifepristone-plus-misoprostol group than the misoprostol-only group (689 minutes vs 901 minutes, p < 0.001).

CONCLUSION(S)

Patients who received mifepristone on the same day as misoprostol had a shorter duration of induction termination and higher rate of success within 12 hours.

Induced abortion

Abortion is common. Data on abortion rates are inexact but can be used to explore trends. Globally, the estimated rate in the period 2010-2014 was 35 abortions per 1000 women (aged 15-44 years), five points less than the rate of 40 for the period 1990-1994. Abortion laws vary around the world but are generally more restrictive in developing countries. Restrictive laws do not necessarily deter women from seeking abortion but often lead to unsafe practice with significant mortality and morbidity. While a legal framework for abortion is a prerequisite for availability, many laws, which are not evidence based, restrict availability and delay access. Abortion should be available in the interests of public health and any legal framework should be as permissive as possible in order to promote access. In the absence of legal access, harm reduction strategies are needed to reduce abortion-related mortality and morbidity. Abortion can be performed surgically (in the first trimester, by manual or electric vacuum aspiration) or with medication: both are safe and effective. Cervical priming facilitates surgery and reduces the risk of incomplete abortion. Diagnosis of incomplete abortion should be made on clinical grounds, not by ultrasound. Septic abortion is a common cause of maternal death almost always following unsafe abortion and thus largely preventable. While routine follow-up after abortion is unnecessary, all women should be offered a contraceptive method immediately after the abortion. This, together with improved education and other interventions, may succeed in reducing unintended pregnancy.

Simultaneous administration of mifepristone and misoprostol for early termination of pregnancy: a randomized controlled trial

AIM

To compare the efficacy of different intervals of misoprostol administration (simultaneously vis-à-vis 24 h), after mifepristone, in women undergoing medical termination of pregnancy up to gestation of 49 days.

METHODS

Eighty eligible women with single intrauterine pregnancy of ≤ 7 weeks of gestation requesting abortion were randomized to receive either 200 mg of mifepristone orally and 400 μg of misoprostol vaginally simultaneously (Group 1) or at 24-h interval (Group 2).Women who had no bleeding after the drugs were offered a second dose of misoprostol 24 h after the first dose. All patients were followed up on day 14. Primary outcome measure was the complete abortion rate. Secondary outcome measures were the induction-abortion interval, adverse effects, especially bleeding, and treatment acceptability rate. Treatment was considered a failure if surgical intervention was needed for any indication.

RESULTS

Complete abortion was achieved in 38 women [95%; 95% confidence interval (CI) 88%, 100%] in Group 1 and 39 women (97.50%; 95% CI 93%,100%) in Group 2 (p = 0.56). A second dose of misoprostol was needed in two patients in Group 1 and in only one patient in Group 2. The induction-abortion interval was 6.50 ± 1.48 h in Group 1 and 5.95 ± 1.81 h in Group 2 (p = 0.13). The difference in frequency of adverse effects in the two groups was statistically insignificant (p = 0.18). The treatment acceptability rate was 97.50% in Group 1 and 95% in Group 2 (p = 0.56).

CONCLUSION

Simultaneous administration of mifepristone and 400 μg vaginal misoprostol is an effective alternative to standard regimens for medical abortion up to 49 days of gestation.

Is mifepristone 100mg an effective alternative to standard dose for medical abortion

OBJECTIVE

To study the efficacy of a low dose of mifepristone (100 mg) in combination with misoprostol, in women undergoing medical termination of pregnancy up to gestation of 49 days.

MATERIAL AND METHODS

A prospective study was performed in 50 women (mean age 26.54±3.68 years) with single intrauterine pregnancy of up to 49 days of gestation, presenting to our institution between November 2007 and October 2009. 100 mg mifepristone was given orally, followed 24 hours later by 400 micrograms misoprostol vaginally. Misoprostol 400 micrograms was repeated vaginally on the third day if indicated. The primary outcome of complete abortion rate and secondary outcomes of induction-abortion interval and adverse effects, especially bleeding, were assessed.

RESULTS

Mean period of gestation was 38.74±3.90 days. None of the women expelled the products of conception before misoprostol insertion. A second dose of misoprostol was needed in four patients. Complete abortion was achieved in 94.00% of patients, incomplete abortion in 4% and missed abortion in 2%. Approximately all the women reported one or more adverse effects but none of them had any serious ones, the most common being pain in 42 (84%) women followed by nausea, vomiting, fever and diarrhoea in 12 (24%), 6 (12%), 4 (8%) and 3 (6%) women respectively. The overall acceptability rate of the dosing regimen in our study was 94%.

CONCLUSION

A regimen of low dose mifepristone (100 mg) followed 24 hours later by vaginal misoprostol can be safely and effectively used for early abortion.