Predictors of uterine evacuation following early medical abortion with mifepristone and misoprostol

Induced Abortion After Previous Caesarean Section: A Scoping Review

BACKGROUND

Previous caesarean section (CS) is increasingly common among women undergoing induced abortion.

AIMS

To map and analyse existing literature on abortion safety, outcomes and management in those with previous CS.

MATERIALS AND METHODS

Four databases were systematically searched from inception to July 2024. Primary human studies in English reporting on outcomes, safety or management of first- or second-trimester medical (MToP) or surgical (SToP) abortion in women with previous CS were included. Uterine rupture incidence was analysed cumulatively in the first and secondtrimesters by the number of CS and the type of prostaglandin used. Data on the efficacy and safety of MToP and SToP, including studies reporting on the management of abortion in the setting of abnormal placentation, were collected and analysed by theme.

RESULTS

In total, 164 articles met inclusion criteria. Incidence of uterine rupture in first-trimester MToP was 0 of 2194 cases, in second-trimester misoprostol MToP in those with 1 previous CS was 0.5% (10/1910) and 2.2% (18/835) in women with ≥ 2 CS (p < 0.001). Mifepristone priming did not increase the rupture rate in second-trimester MToP (p = 0.77). Previous CS was a modest risk factor for retained products after MToP across both trimesters (OR 1.48, CI 1.29-1.70).

CONCLUSION

Medical and surgical abortion in the first and second trimester appears safe in women with prior CS; however, risks include uterine rupture, need for surgical intervention and haemorrhage from undiagnosed placenta accreta. Further research and guidance are needed on managing abortion after previous classical CS, ≥ 3 previous CS and those with abnormally invasive placenta.

Weight and Procedural Abortion Complications: A Systematic Review

OBJECTIVE

To systematically assess the existing empiric evidence regarding a potential relationship between higher body weight and procedural abortion complications.

DATA SOURCES

EMBASE, MEDLINE, CINAHL, Web of Science, Google Scholar, and Clinicaltrials.gov were searched.

METHODS OF STUDY SELECTION

Our search identified 409 studies, which were uploaded to Covidence for review management; 133 duplicates were automatically removed. A team of two reviewers screened 276 studies, and a third reviewer resolved conflicts. Studies were included if they 1) consisted of peer-reviewed research published between 2010 and 2022, 2) were conducted in the United States, 3) included people with a higher body weight (body mass index [BMI] 30 or higher) in the study sample, and 4) assessed at least one outcome of procedural abortion safety stratified by a measure of body weight.

TABULATION, INTEGRATION, AND RESULTS

We extracted study data using Covidence and calculated an odds ratio for each study to facilitate the synthesis of results. Six studies assessing a total of 38,960 participants were included. No studies found a significant relationship between procedural abortion complications and higher body weight overall. Subgroup analysis from one study identified a significant increase in complications specifically among participants with BMIs higher than 40 who had second-trimester abortions. All studies used a retrospective cohort design and fulfilled Newcastle-Ottawa Scale criteria to be considered good quality. Studies varied in terms of clinical settings, patient populations, gestations assessed, clinician training levels, and care protocols.

CONCLUSION

Overall, higher body weight was not associated with an increased risk of procedural abortion complications in the included studies. The practice of referring patients undergoing procedural abortion with a higher body weight for hospital-based care is not based on recent safety evidence. On the contrary, this practice threatens the health of people with a higher body weight by potentially delaying their access to abortion care, extending their pregnancies into later gestations, and blocking their ability to access an abortion altogether.

Development and validation of a risk assessment model for predicting the failure of early medical abortions: A clinical prediction model study based on a systematic review and meta-analysis

OBJECTIVE

As the first model in predicting the failure of early medical abortion (EMA) was inefficient, this study aims to develop and validate a risk assessment model for predicting the failure of EMAs more accurately in a clinical setting.

METHODS

The derivation cohort was obtained from a comprehensive systematic review and meta-analysis. The clinically significant risk factors were identified and combined with their corresponding odds ratios to establish a risk assessment model. The risk factors were assigned scores based on their respective weightings. The model's performance was evaluated by an external validation cohort obtained from a tertiary hospital. The outcome was defined as the incidence of EMA failure.

RESULTS

A total of 126,420 patients who had undergone medical abortions were included in the systematic review and meta-analysis, and the pooled failure rate was 6.7%. The final risk factors consisted of gestational age, maternal age, parity, previous termination of pregnancy, marital status, type of residence, and differences between gestational age calculated using the last menstrual period and that measured via ultrasound. The risk factors were assigned scores based on their respective weightings, with a maximum score of 19. The clinical prediction model exhibited a good discrimination, as validated by external verification (402 patients) with an area under the curve of 0.857 (95% confidence interval 0.804-0.910). The optimal cutoff value was determined to be 13.5 points, yielding a sensitivity of 83.3% and specificity of 75.4%.

CONCLUSION

This study effectively establishes a simple risk assessment model including seven routinely available clinical parameters for predicting EMA failure. In preliminary validation, this model demonstrates good performance in terms of predictive efficiency, accuracy, calibration, and clinical benefit. However, more research and validation are warranted for future application.

TRIAL REGISTRATION NUMBER

CRD42023485388.

Clinical factors associated with subsequent surgical intervention in women undergoing early medical termination of viable or non-viable pregnancies

Introduction

Mifepristone-misoprostol treatment for medical abortion and miscarriage are safe and effective. This study aimed to assess clinical factors associated with subsequent surgical intervention after medical termination of early viable or non-viable pregnancy.

Methods

This retrospective, single-center study included women who underwent medical abortion at Taipei Medical University between January 2010 and December 2019. A total of 1,561 subjects, with 1,080 viable and 481 non-viable pregnancies, who were treated with oral mifepristone 600 mg followed by misoprostol 600 mg 48 h later were included. Data of all pregnancies and medical termination of pregnancy were evaluated using regression analysis. The main outcome was successful termination of pregnancy.

Results

The success rate of medical abortion was comparable in women with viable and non-viable (92.13% vs. 92.93%) pregnancies. Besides retained tissue, more existing pregnancies with ultrasonographic findings were found in the non-viable pregnancy group than in the viable pregnancy group (29.4% vs. 14.1%, p = 0.011). Multivariate analysis showed that previous delivery was an independent risk factor for failed medical abortion among all included cases. In women with viable pregnancy, longer gestational age [adjusted odds ratio (aOR): 1.483, 95% confidence interval (CI): 1.224-1.797, p < 0.001] and previous Cesarean delivery (aOR: 2.177, 95% CI: 1.167-40.62, p = 0.014) were independent risk factors for failed medical abortion. Number of Cesarean deliveries (aOR: 1.448, 95% CI: 1.029-2.039, p = 0.034) was an independent risk factor for failed medication abortion in women with non-viable pregnancies.

Conclusion

This is the first cohort study to identify risk factors for subsequent surgical intervention in women with viable or non-viable pregnancies who had undergone early medically induced abortions. The success rate of medical abortion is comparable in women with viable and non-viable pregnancies. Previous delivery is an independent risk factor for failed medical abortion. Clinical follow-up may be necessary for women who are at risk of subsequent surgical intervention.

Effect of obesity on the time to a successful medical abortion with misoprostol in first-trimester missed abortion

OBJECTIVE

To evaluate the efficacy of misoprostol used in first-trimester abortion in obese women and to determine whether obesity is associated with time to a successful medical abortion.

METHODS

The records of patients diagnosed with missed abortion at our clinic between 2018 and 2021 were retrospectively reviewed. All women aged 18 to 45 years who were diagnosed with missed abortion in the first trimester and treated with misoprostol were included in the study. The cases were divided into two groups: obese (body mass index [BMI] ≥ 30 kg/m2) and non-obese (BMI < 30 kg/m2). First, they were simultaneously administered 200 μg misoprostol orally and 400 μg vaginally. After the first misoprostol administration, the dose was repeated vaginally at 400 μg every three hours if necessary. The effect of obesity on the time taken to achieve a medical abortion was evaluated.

RESULTS

A successful medical abortion occurred in 45.2% of the women in the obese group and 69.0% of those in the non-obese group. The time to uterine evacuation was 8.24 ± 4.03 h in the obese group and 6.35 ± 3.54 h in the non-obese group. The relationship between obesity and time to a successful medical abortion was evaluated using the Kaplan-Meier curve, which showed a significant difference between the two groups (p = 0.028).

CONCLUSION

Our findings show that obesity affects time to a successful medical abortion. In addition, the rate of successful medical abortion after misoprostol administration was lower in the obese women.

The diagnostic value of transvaginal color Doppler ultrasonography plus serum β-HCG dynamic monitoring in intrauterine residue after medical abortion

To probe the diagnostic value of transvaginal color Doppler ultrasonography plus serum β-human chorionic gonadotropin (β-HCG) dynamic monitoring in intrauterine residue after medical abortion.In total, 200 pregnant women undergoing medical abortion in our institution from January 2017 to December 2019 were picked, and assigned to either group A (n = 75, with residue) or group B (n = 125, without residue). We detected serum β-HCG, progesterone (P), follicle stimulating estrogen (FSH) levels and ultrasonic indicators endometrial thickness (ET), peak systolic velocity (PSV), resistance index (RI) values, dissected correlation of indicators using logistic linear regression analysis, and prospected the diagnostic value of relevant indicators in intrauterine residue after medical abortion utilizingreceiver operating characteristic curve.At 7 days after abortion (T3), total vaginal bleeding and visual analogue scalescore in group A were saliently higher in contrast to group B ( P < .05). At 72 hours after abortion (T2) and T3, serum β-HCG, P and FSH levels declined strikingly in both groups, but group B held plainly higher decrease rate than group A ( P HC.05). At T3, ET and PSV levels in both groups considerably waned, whereas RI levels notedly waxed, and group B owned markedly higher decrease/increase than group A ( P wa.05). At T3, serum β-HCG in group A possessed positive association with serum P, FSH, intrauterine ET, PSV levels separately ( P HC.05), whereas negative link with RI levels ( P , .05). The specificity and sensitivity of β-HCG, P, FSH, β-HCG/ET, β-HCG/PSV and β-HCG/RI in the diagnosis of intrauterine residue after medical abortion were high ( P < .05).Serum β-HCG dynamic monitoring plus transvaginal color Doppler ultrasonography is of great value in diagnosing intrauterine residue after medical abortion. Serum β-HCG, P, FSH levels can be combined with the results of intrauterine ET, PSV, RI values, so as to boost the diagnostic accuracy of the intrauterine residue after medical abortion.

Predicting the likelihood of successful medical treatment of early pregnancy loss: development and internal validation of a clinical prediction model

STUDY QUESTION

What are clinical predictors for successful medical treatment in case of early pregnancy loss (EPL)?

SUMMARY ANSWER

Use of mifepristone, BMI, number of previous uterine aspirations and the presence of minor clinical symptoms (slight vaginal bleeding or some abdominal cramps) at treatment start are predictors for successful medical treatment in case of EPL.

WHAT IS KNOWN ALREADY

Success rates of medical treatment for EPL vary strongly, between but also within different treatment regimens. Up until now, although some predictors have been identified, no clinical prediction model has been developed yet.

STUDY DESIGN, SIZE, DURATION

Secondary analysis of a multicentre randomized controlled trial in 17 Dutch hospitals, executed between 28 June 2018 and 8 January 2020.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Women with a non-viable pregnancy between 6 and 14 weeks of gestational age, who opted for medical treatment after a minimum of 1 week of unsuccessful expectant management. Potential predictors for successful medical treatment of EPL were chosen based on literature and expert opinions. We internally validated the prediction model using bootstrapping techniques.

MAIN RESULTS AND THE ROLE OF CHANCE

237 out of 344 women had a successful medical EPL treatment (68.9%). The model includes the following variables: use of mifepristone, BMI, number of previous uterine aspirations and the presence of minor clinical symptoms (slight vaginal bleeding or some abdominal cramps) at treatment start. The model shows a moderate capacity to discriminate between success and failure of treatment, with an AUC of 67.6% (95% CI = 64.9-70.3%). The model had a good fit comparing predicted to observed probabilities of success but might underestimate treatment success in women with a predicted probability of success of ∼70%.

LIMITATIONS, REASONS FOR CAUTION

The vast majority (90.4%) of women were Caucasian, potentially leading to less optimal model performance in a non-Caucasian population. Limitations of our model are that we have not yet been able to externally validate its performance and clinical impact, and the moderate accuracy of the prediction model of 0.67.

WIDER IMPLICATIONS OF THE FINDINGS

We developed a prediction model, aimed to improve and personalize counselling for medical treatment of EPL by providing a woman with her individual chance of complete evacuation.

STUDY FUNDING/COMPETING INTEREST(S)

The Triple M Trial, upon which this secondary analysis was performed, was funded by the Healthcare Insurers Innovation Foundation (project number 3080 B15-191).

TRIAL REGISTRATION NUMBER

Clinicaltrials.gov: NCT03212352.

[Evaluation of the success of medical abortion by a plasma hCG control threshold]

OBJECTIVES

In France, monitoring of the success of medical abortion is recommended 2 to 3 weeks after the procedure. However, there is no clear consensus on the modalities of this monitoring. The main objective of this study is to identify a threshold of serum hCG (human chorionic gonadotropin) control for medical abortions ≤7 weeks of gestation below which success can be confirmed without recourse to pelvic ultrasound.

METHODS

This is a retrospective multicenter study conducted over a 14-month period. The serum hCG level, measured between the 15th and 25th day following the abortion, was compared with the results of the pelvic ultrasound performed at the follow-up visit. Ultrasound failure was defined as retention or persistent pregnancy.

RESULTS

Among the 624 women included, the failure rate was 22.3%, including 86.3% of retentions, 8.6% of pregnancies stopped and 5% of pregnancies progressed. Using a ROC curve, the threshold value of hCG found to exclude failure at 95% was 253 IU/l (AUC=0.9202, sensitivity=84.17%, specificity=85.95% and positive predictive value [PPV]=63%).

CONCLUSIONS

A serum hCG level ≤253 IU/l is sufficient to affirm the efficacy of medical abortion. However, since PPV is only 63% for this threshold, ultrasound should be reserved for women with high hCG levels.

To operate or to wait? Doppler indices as predictors for medical termination for first trimester missed abortion

Purpose: Missed abortion is a common obstetrical problem with a high incidence. Evidence supports a change in approach from the traditional dilatation and curettage to medical; however, few studies have investigated the prediction success of the medical approach. This study investigates whether first trimester missed abortion can be successfully terminated using Doppler indices, such as resistance index (RI) and pulsatility index (PI), as predictors. Material and Method: In this prospective study, the sample is made up of 78 patients, with a first trimester missed abortion range of 6-13 weeks of pregnancy who meets the maternal parameters as well as transvaginal Doppler indices, RI and PI. The participants were subdivided into 3 groups based on their response to sublingual misoprostol and weeks needed to terminate as Groups I (43/78), II (26/78), and III (9/78) aborted in the first, second, and third weeks, respectively. Results: Age, BMI, and gestational age of dead fetus were not significant for Groups I, II, and III with P = 0.13, P = 0.13, and P = 0.35, respectively. Parity and delivery mode showed significant differences (P < 0.0001) between group means of PI and RI. PI for Group I plus II and Group III are 1.53 (0.75-2.70) and 1.58 (1.10-2.10), respectively. RI for Group I plus II and Group III are 0.71 (0.50-1.00) and 0.80 (0.69-0.92), respectively. The coefficient of correlation proves that RI is the primary predictor of successful termination of a first trimester missed abortion with a cut-off value of 0.74 with associated sensitivity and specificity of 68.7% and 56.7%, respectively. Conclusions: Increased parity and a history of vaginal delivery, in addition to measured RI, were predictors of successful termination of a first trimester missed abortion. These results may be used in counseling patients to decide safest and most suitable option to terminate a first trimester missed abortion, depending on their demographic criteria and ultrasound scores.

Efficacy of mifepristone - Prostaglandin analogue combination in medical termination of pregnancy up to and beyond 7 weeks of amenorrhea: The RYMMa study

OBJECTIVE

To assess, in real-life conditions, the success rate of the protocol mifepristone 600 mg / prostaglandin analogue (PG) in women requesting medical termination of pregnancy (MToP) either up to or beyond 7 weeks of amenorrhea (WA).

STUDY DESIGN

The study was performed between 2015 and 2016. This was a non-interventional prospective, multicentre, longitudinal study conducted in France, among a sample of public and/or private centres dealing with MToP. Characteristics of women, term of Mtop, modality of PG used were reported. The primary outcome was success of MToP, defined as complete abortion without surgical procedure.

RESULTS

A total of 893 pregnant women with less than the legal term of 14 WA were included in this study: 490 (54.9 %) ≤7 WA and 403 (45.1 %) >7 WA comprising 29 > 9 WA. The mean age of women was 28.1 ± 6.8 years and the one of pregnancy was 7.0 WA ± 1.3 WA. The most frequently used PG combined to mifepristone 600 mg was misoprostol 400 μg (57.0 % ≤7 WA and 35.1 % >7 WA) or 800 μg per os (oral or oral transmucosal) (27.5 % ≤7 WA and 40.1 % >7 WA). Vaginal misoprostol (6.4 %, N = 48) and gemeprost (5.2 %, N = 39) were less used. In women ≤7 WA (N = 422) and women >7 WA (N = 354) for whom result of the MToP was collected, success rates were 94.5 % (95 %CI 91.9 %-96.5 %) and 92.4 % (95 %CI 89.1 %-94.9 %), respectively (p = 0.219). In multivariate regression analysis, three factors were significantly associated with a higher risk of MToP failure: increased number of previous pregnancies (OR = 1.233; 95 %CI 1.086-1.401 for one pregnancy), increased number of previous surgical ToPs (OR = 1.563; 95 %CI 1.036-2.359 for one ToP) and increased interval between mifepristone and PG intake (OR = 1.061; 95 %CI 1.012-1.112 for one hour). Term of pregnancy (OR = 1.497; 95 %CI 0.833-2.690 for ≤7 WA vs >7WA), administration route (OR = 1.553; 95 %CI 0.488-4.936 for oral vs oral transmucosal; and OR = 1.216; 95 %CI 0.625-2.366 for vaginal vs oral transmucosal), and dose of misoprostol (OR = 1.000; 95 %CI 0.999-1.001), were not associated with the risk of failure. Overall, tolerance was good.

CONCLUSION

This study showed, in real-life settings, a high rate of success for MToP using mifepristone 600 mg, independent of the pregnancy term and the therapeutic protocol used. MToP was safe and well tolerated however only a small number of women beyond 9 WA have been included.

Risk factors for surgical intervention of early medical abortion

BACKGROUND

By being noninvasive, medical termination of pregnancy has increased worldwide access to abortion and improved safety of unsafe abortion. However, secondary surgical intervention is the most frequent complication to medical abortion.

OBJECTIVE

We aimed to identify and quantify risk factors for surgical intervention in women undergoing medically induced termination of pregnancy before 9 completed weeks of gestation.

STUDY DESIGN

We conducted a nationwide cohort study, including all pregnancies terminated before 63 gestational days in women aged 15-49 years during the period 2005-2015. Induction regimen was 200 mg mifepristone followed 24-48 hours later by 0.8 mg vaginal misoprostol. All included pregnancies were followed up for 8 weeks from mifepristone administration. Data were retrieved from national health registers. Multiple logistic regression provided adjusted odds ratios of surgical intervention with 95% confidence intervals. The discriminative ability of the risk factors in identifying surgical intervention was assessed by cross-validated area under the receiver operating characteristic curve.

RESULTS

Of 86,437 early medical abortions, 5320 (6.2%) underwent a surgical intervention within 8 weeks after induction. The proportion of surgical interventions increased from 3.5% in the 5th to 6th gestational week to 10.3% in week 9, odds ratio, 3.2 (95% confidence interval, 2.9-3.6). Compared with women aged 15-19 years, the risk of surgical intervention increased with increasing maternal age until the age of 30-34 years, odds ratio, 1.7 (95% confidence interval, 1.5-1.9), where after the risk decreased to an odds ratio for age group 40-49 of 1.2 (95% confidence interval, 1.0-1.4). Compared with nulliparous women, a history of only vaginal deliveries with spontaneous delivery of placenta implied an odds ratio of 1.1 (95% confidence interval, 1.0-1.2), women with a history of at least 1 cesarean delivery, an odds ratio of 1.5 (95% confidence interval, 1.3-1.6), and women having experienced a manual removal of placenta after a vaginal birth, an odds ratio of 2.0 (95% confidence interval, 1.7-2.4). Previous medically induced abortion decreased the risk of surgical intervention, odds ratio 0.84 (95% confidence interval, 0.78-0.91), whereas previous early (before 56 days of gestation) surgically induced abortion implied a 53% (95% confidence interval, 1.4-1.7) increased risk of surgical intervention. Previous surgical abortion after 55 days of gestation increased the risk by 17% (95% confidence interval, 1.1-1.3). The area under the receiver operating characteristic curve of the model including all quantified risk factors was 63% (95% confidence interval, 62-64%).

CONCLUSION

Gestational age, maternal age, previous deliveries, and history of medically and surgically induced abortions all had a significant influence on the risk of surgical intervention of early medical abortion. However, inclusion of all quantified risk factors still left most interventions unpredictable.

Serum hCG threshold to assess medical abortion success

OBJECTIVES

The main aim of the study was to establish a threshold for serum human chorionic gonadotropin (hCG) level that ruled out ongoing pregnancy after induced medical abortion (MA). The secondary aim was to discover risk factors for the need for uterine aspiration.

METHODS

This prospective study included women who underwent MA with mifepristone-misoprostol at ≤9 weeks of gestation between 2012 and 2014. Serum hCG levels were measured 14-21 days after MA. The main outcome measure, ongoing pregnancy, was defined as the presence of an embryo with cardiac activity on transvaginal ultrasonography after MA. The receiver operating characteristic curve was plotted to determine the optimal serum hCG threshold. Risk factors for the need for uterine aspiration were calculated using multivariate logistic regression and expressed as odds ratios (ORs) with 95% confidence intervals (CIs).

RESULTS

The study included 814 women. Mean gestational age was 46.5 ± 7.4 days for ongoing pregnancies and 44.2 ± 4.8 days for MA success (p = .43). The ongoing pregnancy rate after MA was 0.9%. A serum hCG threshold ≥900 IU/l to diagnose ongoing pregnancy gave 100% sensitivity and 81.5% specificity, compared with 85.7% sensitivity and 83.5% specificity using a threshold ≥1000 IU/l. Independent risk factors for uterine aspiration requirement were: gravidity (OR 3.8; 95% CI 1.1, 13.2; p = .001), gestational age >6 weeks (OR 6.0; 95% CI 1.8, 6.0; p = .006) and previous surgical abortion (OR 2.4; 95% CI 1.1, 5.2; p < .001).

CONCLUSION

Serum hCG measurement <900 IU/l, 14-21 days after MA, is an efficient strategy for excluding ongoing pregnancy after first trimester MA.