Midtrimester abortion induced by hyperosmolar urea and prostaglandin F2 alpha in patients with previous cesarean section: clinical course and potential for uterine rupture

No. 360-Induced Abortion: Surgical Abortion and Second Trimester Medical Methods

OBJECTIVE

This guideline reviews evidence relating to the provision of surgical induced abortion (IA) and second trimester medical abortion, including pre- and post-procedural care.

INTENDED USERS

Gynaecologists, family physicians, nurses, midwives, residents, and other health care providers who currently or intend to provide and/or teach IAs.

TARGET POPULATION

Women with an unintended or abnormal first or second trimester pregnancy.

EVIDENCE

PubMed, Medline, and the Cochrane Database were searched using the key words: first-trimester surgical abortion, second-trimester surgical abortion, second-trimester medical abortion, dilation and evacuation, induction abortion, feticide, cervical preparation, cervical dilation, abortion complications. Results were restricted to English or French systematic reviews, randomized controlled trials, clinical trials, and observational studies published from 1979 to July 2017. National and international clinical practice guidelines were consulted for review. Grey literature was not searched.

VALUES

The quality of evidence in this document was rated using the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) methodology framework. The summary of findings is available upon request.

BENEFITS, HARMS, AND/OR COSTS

IA is safe and effective. The benefits of IA outweigh the potential harms or costs. No new direct harms or costs identified with these guidelines.

Mifepristone combined with ethacridine lactate for the second-trimester pregnancy termination in women with placenta previa and/or prior cesarean deliveries

PURPOSE

This study was aimed to evaluate the safety and efficacy of the second-trimester medical abortions using mifepristone and ethacridine lactate in women with placenta previa and/or prior cesarean deliveries.

METHODS

The patients who underwent a second-trimester pregnancy termination from January 2009 to December 2015 were retrospectively analyzed. The eligible patients were assigned to four groups based on placentation and cesarean history. The abortion interval (AI), blood loss, hospital stays, incidence of curettage, and transfusion were reviewed.

RESULTS

Two women underwent cesarean sections for placenta increta. Finally, 443 patients were enrolled in this study, including 92 with placenta previa, 153 with prior cesarean deliveries, 36 with the both factors, and 236 with normal placentation and no cesarean delivery history. All the included cases had a successful vaginal delivery. There was no significant difference in AI, hospital stay, rate of hemorrhage, and transfusion among the four groups. Patients with prior cesarean section had higher blood loss than the normal group (P = 0.0017), as well as patients with both placenta previa and prior cesarean (P = 0.0018). However, there was no obvious blood loss in patients with placenta previa when compared with normal placetal patients (P = 0.23). No uterine rupture occurred in all patients.

CONCLUSIONS

Mifepristone combined with ethacridine lactate is safe and effective for patients with low placentation or/and prior cesarean in the second-trimester pregnancy termination.

Cervical ripening agents in the second trimester of pregnancy in women with a scarred uterus: a systematic review and metaanalysis of observational studies

OBJECTIVE

The aim of this systematic review and metaanalysis was to determine the efficacy and safety of cervical ripening agents in the second trimester of pregnancy in patients with previous cesarean delivery.

STUDY DESIGN

Data sources were PubMed, EMBASE, CINAHL, LILACS, Google Scholar, and clinicaltrials.gov (1983 through 2015). Eligibility criteria were cohort or cross-sectional studies that reported on efficacy and safety of cervical ripening agents in patients with previous cesarean delivery. Efficacy was determined based on the proportion of patients achieving vaginal delivery and vaginal delivery within 24 hours following administration of a cervical ripening agent. Safety was assessed by the risk of uterine rupture and complications such as retained placental products, blood transfusion requirement, and endometritis, when available, as secondary outcomes. Of the 176 studies identified, 38 met the inclusion criteria. Of these, 17 studies were descriptive and 21 studies compared the efficacy and safety of cervical ripening agents between patients with previous cesarean and those with no previous cesarean. From included studies, we abstracted data on cervical ripening agents and estimated the pooled risk differences and risk ratios with 95% confidence intervals. To account for between-study heterogeneity, we estimated risk ratios based on underlying random effects analyses. Publication bias was assessed via funnel plots and across-study heterogeneity was assessed based on the I(2) measure.

RESULTS

The most commonly used agent was PGE1. In descriptive studies, PGE1 was associated with a vaginal delivery rate of 96.8%, of which 76.3% occurred within 24 hours, uterine rupture in 0.8%, retained placenta in 10.8%, and endometritis in 3.9% in patients with ≥1 cesarean. In comparative studies, the use of PGE1, PGE2, and mechanical methods (laminaria and dilation and curettage) were equally efficacious in achieving vaginal delivery between patients with and without prior cesarean (risk ratio, 0.99, and 95% confidence interval, 0.98-1.00; risk ratio, 1.00, and 95% confidence interval, 0.98-1.02; and risk ratio, 1.00, and 95% confidence interval, 0.98-1.01; respectively). In patients with history of ≥1 cesarean the use of PGE1 was associated with higher risk of uterine rupture (risk ratio, 6.57; 95% confidence interval, 2.21-19.52) and retained placenta (risk ratio, 1.21; 95% confidence interval, 1.03-1.43) compared to women without a prior cesarean. However, the risk of uterine rupture among women with history of only 1 cesarean (0.47%) was not statistically significant (risk ratio, 2.36; 95% confidence interval, 0.39-14.32), whereas among those with history of ≥2 cesareans (2.5%) was increased as compared to those with no previous cesarean (0.08%) (risk ratio, 17.55; 95% confidence interval, 3.00-102.8). Funnel plots did not demonstrate any clear evidence of publication bias. Across-study heterogeneity ranged from 0-81%.

CONCLUSION

This systematic review and metaanalysis provides evidence that PGE1, PGE2, and mechanical methods are efficacious for achieving vaginal delivery in women with previous cesarean delivery. The use of prostaglandin PGE1 in the second trimester was not associated with significantly increased risk for uterine rupture among women with only 1 cesarean; however, this risk was substantially increased among women with ≥2 cesareans although the absolute risk appeared to be relatively small.

Safety of late second-trimester pregnancy termination by laminaria dilatation and evacuation in patients with previous multiple cesarean sections

OBJECTIVE

To assess whether there is an increased perioperative risk in termination of late second-trimester pregnancy after multiple cesarean sections by laminaria dilatation and evacuation.

STUDY DESIGN

During the period between January 2002 and June 2008, 636 consecutive patients underwent late second-trimester (17-24 weeks) pregnancy terminations by dilatation and evacuation. Patients were divided into 3 subgroups: those with no previous cesarean section (n = 545), those with 1 previous cesarean section (n = 59), and those with several previous cesarean sections (n = 32).

RESULTS

There were no significant differences in major perioperative complications, such as anesthetic complications, need for blood transfusion, and cervical lacerations comparing the 3 subgroups. Importantly, there were neither cases of uterine perforation nor retained products of conception in the 3 subgroups.

CONCLUSION

Late second-trimester pregnancy termination after multiple cesarean sections by laminaria dilatation and evacuation is probably not associated with an increased perioperative risk. Larger studies are needed to empower this study.

Second trimester medical abortion with mifepristone-misoprostol and misoprostol alone: a review of methods and management

Second trimester abortions constitute 10-15% of all induced abortions worldwide but are responsible for two-thirds of major abortion-related complications. During the last decade, medical methods for second trimester induced abortion have been considerably improved and become safe and more accessible. Today, in most cases, safe and efficient medical abortion services can be offered or improved by minor changes in existing health care facilities. Second trimester medical abortion can be provided by a nurse-midwife with the back-up of a gynaecologist. Because of the potential for heavy vaginal bleeding and serious complications, it is advisable that second trimester terminations take place in a health care facility where blood transfusion and emergency surgery (including laparotomy) are available. This article provides basic information on regimens recommended for second trimester medical abortion. The combination of mifepristone and misoprostol is now an established and highly effective method for second trimester abortion. Where mifepristone is not available or affordable, misoprostol alone has also been shown to be effective, although a higher total dose is needed and efficacy is lower than for the combined regimen. Therefore, whenever possible, the combined regimen should be used. Efforts should be made to reduce unnecessary surgical evacuation of the uterus after expulsion of the fetus. Future studies should focus on improving pain management, the treatment of women with failed medical abortion after 24 hours, and the safety of medical abortion regimens in women with a previous caesarean section or uterine scar.

Sonographic findings of uterine rupture with expulsion of the fetus into broad ligament

We report the sonographic findings of a rare case of uterine rupture with extrusion of the fetus into the broad ligament during a second-trimester abortion. Sonography revealed the empty uterus with an indistinct defect on the side wall and the dead fetus lying outside, surrounded by a thin membrane. At surgery, the uterine rupture was confirmed with the fetus lying in the broad ligament. This study shows the importance of timely sonography in second-trimester abortion, enabling immediate management and preventing further complications.

Mid-trimester induced abortion: a review

Mid-trimester abortion constitutes 10-15% of all induced abortion. The aim of this article is to provide a review of the current literature of mid-trimester methods of abortion with respect to efficacy, side effects and acceptability. There have been continuing efforts to improve the abortion technology in terms of effectiveness, technical ease of performance, acceptability and reduction of side effects and complications. During the last decade, medical methods for mid-trimester induced abortion have shown a considerable development and have become safe and more accessible. The combination of mifepristone and misoprostol is now an established and highly effective method for termination of pregnancy (TOP). Advantages and disadvantages of medical versus surgical methods are discussed. Randomized studies are lacking, and more studies on pain treatment and the safety of any method used in patients with a previous uterine scar are debated, and data are scarce. Pain management in abortion requires special attention. This review highlights the need for randomized studies to set guidelines for mid-trimester abortion methods in terms of safety and acceptability as well as for better analgesic regimens.

Misoprostol for Second-Trimester Pregnancy Termination in Women With a Prior Cesarean Delivery

OBJECTIVE

To evaluate the use of misoprostol in second-trimester abortion in women with prior cesarean deliveries.

METHODS

A review of women with prior cesarean deliveries undergoing abortion at 14-28 weeks of gestation for a fetal anomaly over a 7.5-year period. Outcome data were compared with a contemporaneous cohort of women with unscarred uteri undergoing the same procedure. Misoprostol was used to induce abortion in all cases, and a variety of dosage regimens were used, the most frequent being 400 mug vaginally every 6 hours (71.3%).

RESULTS

During the study period, 720 consecutive women underwent a second-trimester abortion for a fetal anomaly using misoprostol. One hundred one women (14%) had at least 1 prior cesarean delivery: 78 women had 1, 19 women had 2, and 4 women had 3 prior cesarean deliveries. Women with a prior cesarean birth were significantly older (30 years [interquartile range 26-35] versus 33 years [29-37], no cesarean delivery versus cesarean delivery, P = < .001) and of increased parity. The median gestational age at delivery was 19.4 weeks (interquartile range 18-20.7) versus 19.3 weeks (17.7-21), no cesarean delivery versus cesarean delivery, P = .48. The presence of a prior uterine scar did not impact upon abortion duration (16.6 hours [12.1-23.8] versus 14.5 hours [11.4-21.4], no cesarean delivery versus cesarean delivery, P = .07). No differences in blood loss, major hemorrhage, or blood transfusion occurred. There was no case of uterine rupture or hysterectomy.

CONCLUSION

In second-trimester abortion, the use of misoprostol in women with prior cesarean delivery was not associated with an excess of complications compared with women with unscarred uteri.

LEVEL OF EVIDENCE

II-2.

Misoprostol for second trimester pregnancy termination in women with prior caesarean section

OBJECTIVE

To examine whether a previous caesarean section increases the risk for complications in women undergoing a mid-trimester pregnancy termination by labour induction.

DESIGN

Retrospective analysis of case records between 1997 and 2002.

SETTING

Fetal Medicine Unit of a large teaching hospital.

POPULATION

One hundred and eight women with a previous caesarean section (study group) and 216 women without such a history (controls), who underwent a second trimester termination of pregnancy.

METHODS

All the terminations were performed between 17 and 24 weeks of gestation by using 400 mug of oral administration of misoprostol in combination with 400 mug of intravaginal misoprostol. The same dose of intravaginal misoprostol was repeated every 6 hours for a maximum of five doses.

MAIN OUTCOME MEASURES

Severe haemorrhage requiring blood transfusion, post-abortal infection, retained placenta and uterine rupture.

RESULT

Complications occurred in 16 out of 108 women of the study group (15%) and in 26 out of 216 of the controls (12%), with only one ruptured uterus in the control group.

CONCLUSION

We found no evidence that a previous caesarean delivery affects the incidence of complications when women with such a history undergo a mid-trimester pregnancy termination with misoprostol.

Prostaglandins for induction of second-trimester termination and intrauterine death

The introduction of synthetic prostaglandin has revolutionized the treatment protocol for induction of second-trimester abortion and intrauterine death. Gemeprost is the only licensed synthetic prostaglandin analogue for second-trimester abortion in the United Kingdom. However, it is expensive and needs to be stored in a refrigerator. Misoprostol is marketed for use in the prevention and treatment of peptic ulcer. It is inexpensive and can be stored at room temperature. It has been widely used for induction of second-trimester abortion and intrauterine death. Misoprostol, 400 microg given vaginally every 3hours, is probably the optimal regimen for second-trimester abortion. The combination of misoprostol and mifepristone significantly reduced the induction-to-abortion interval when compared with the misoprostol-only regimen. In addition, misoprostol can also be used as a cervical priming agent prior to dilatation and evacuation in second-trimester abortion.

Induction of labor with vaginal misoprostol for second trimester termination of pregnancy in the scarred uterus

OBJECTIVES

To assess the safety of vaginal misoprostol for second trimester pregnancy termination in patients with a history of cesarean section.

METHODS

A consecutive series of 593 women with pregnancies of 14-26 weeks were studied. A cohort of 56 cases had undergone previous cesarean section delivery. The 528 cases who had no history of prior uterine surgery served as the controls. The termination was carried out according to the regimen used at the time of enrollment, either 600 microg applied at every 6 or every 12 h, or 800 microg applied at every 12 h using the vaginal route.

RESULTS

The median induction to abortion time in the previous cesarean section group (15.1 h) was not significantly different from that of the controls (15.8 h). The median total dosage of misoprostol used was the same for both groups (1200 microg). The rates of incomplete abortion and analgesia usage were significantly higher in the previous cesarean section group as compared with the controls.

CONCLUSIONS

Vaginal misoprostol was effective for the second trimester pregnancy termination but the safety of misoprostol in the scarred uterus cannot be assumed from this study. A large series is needed to reach the power to see the difference.

Complications of midtrimester pregnancy termination: the effect of prior cesarean delivery

OBJECTIVE

Our purpose was to determine whether a prior cesarean delivery affects the incidence of complications in women having an indicated midtrimester medical pregnancy termination.

STUDY DESIGN

A retrospective review of women who underwent a midtrimester medical termination of pregnancy from January 1980 to July 1995 ascertained obstetric history, uterotonic agent(s), and the occurrence of uterine rupture, blood transfusion, or curettage. The frequencies of maternal complications were compared in women with and without a prior cesarean section.

RESULTS

Our study population included 606 women with a mean gestational age of 21.1 +/- 3.1 weeks and a mean maternal age of 26.3 +/- 7 years. Seventy-nine (13%) had undergone a prior cesarean section. There was no significant difference in the need for curettage between women with and without a prior cesarean section. However, there was an increased need for blood transfusions in women with a prior cesarean delivery (11.4% vs 5.3%, odds ratio 2.3, 95% confidence interval 1.1 to 5.0, p = 0.04). The incidence of uterine rupture was significantly higher among women with a prior cesarean (3.8% vs 0.2%, odds ratio 20.8, 95% confidence interval 14.1 to 104, p = 0.008).

CONCLUSION

Our data suggest that a prior cesarean section is a risk factor for uterine rupture and blood transfusion in women having a midtrimester pregnancy termination.

Safety of midtrimester pregnancy termination by laminaria and evacuation in patients with previous cesarean section

OBJECTIVE

The objective of this study was to retrospectively assess whether there was an increased perioperative risk in midtrimester pregnancy termination by laminaria and evacuation associated with a previous uterine scar.

STUDY DESIGN

From 1978 to 1993 1064 patients underwent midtrimester (14 to 22 weeks) pregnancy termination by means of laminaria and evacuation. Of these, 70 patients had a previous uterine scar and are the subjects of this study.

RESULTS

There were no major operative complications, such as anesthetic complications, perforations, or cervical lacerations, in the entire series. Mean operative time (minutes) for induced abortion was statistically similar in the unscarred compared with the scarred uteri groups (8.03 +/- 4.40 vs 7.46 +/- 4.42, respectively) and was statistically different when the indication for evacuation was missed abortion (6.08 +/- 1.86 vs 4.81 +/- 2.11, respectively; p < 0.005). This difference in operative time could be explained by the number of laminaria tents used in each group. Atony with hemorrhage occurred in two patients who underwent induced abortion, and disseminated intravascular coagulation occurred in eight missed abortion cases, but none had scarred uterus.

CONCLUSION

Previous cesarean section scar does not seem to increase the perioperative risk of late termination (14 to 22 weeks) by the laminaria and evacuation technique.

Continuous extraovular prostaglandin F2 alpha instillation for late pregnancy termination in patients with previous cesarean section delivery

Late pregnancy termination by continuous extraovular instillation of prostaglandin F2 alpha (PGF2 alpha) was successfully performed in 13 patients with previous cesarean section (CS) delivery. The indications for pregnancy termination were intrauterine fetal demise in nine patients, social indications in two patients. Down's Syndrome in one patient and quadruplets pregnancy in one patient. One patient had a previous classical vertical cesarean section, two had two previous and one three previous low segment transverse (LST) cesarean sections. The other nine patients had one previous low segment transverse cesarean section. The instillation of prostaglandin solution was obtained by using a new double balloon catheter designed for extraovular pregnancy terminations. All patients aborted following the procedure with no complications. The instillation abortion time ranged from 5 1/2 to 20 h (mean 13.3 h).

Uterine rupture during induced mid-trimester abortion

Uterine rupture during induced mid-trimester abortion is infrequent. Often the diagnosis is established only after manual exploration of the uterus, exploratory laparotomy or even autopsy. It is crucial to establish the diagnosis rapidly and to offer efficient treatment, since the unexpected occurrence of this catastrophe adds to its inherent seriousness. Fourteen cases revealed by a Med-line search and two additional personal cases were reviewed. The most common complaint heralding the rupture was abdominal pain and secondary to it there were signs of blood loss, such as vaginal bleeding, decreased hematocrit level and decreased blood pressure. 72% of women with uterine rupture (10 out of 14) did not abort within 24 h after intra-amniotic injection, and 85% (11 out of 13) had large quantities of oxytocin administered for more than 12 h. The rupture occurred predominantly in the lower segment and there was no preference either for the right or left side of the uterus. It was shown that uterine rupture during mid-trimester induced abortion is not unique to women of high parity or old age. The major complications occurring in induced mid-trimester abortions are similar to those seen in patients who deliver in the third trimester.