Concentrated oxytocin plus low-dose prostaglandin E2 compared with prostaglandin E2 vaginal suppositories for second-trimester pregnancy termination

Opposing effects of oxytocin on overt compliance and lasting changes to memory

From infancy we learn to comply with societal norms. However, overt compliance is not necessarily accompanied by a change in internal beliefs. The neuromodulatory processes underlying these different phenomena are not yet understood. Here, we test the role of oxytocin in controlling overt compliance versus internalization of information delivered by a social source. After intranasal oxytocin administration, participants showed enhanced compliance to the erroneous opinion of others. However, this expression was coupled with a decrease in the influence of others on long-term memories. Our data suggest that this dissociation may result from reduced conflict in the face of social pressure, which increases immediate conforming behavior, but reduces processing required for deep encoding. These findings reveal a neurobiological control system that oppositely affects internalization and overt compliance.

Medical methods for mid-trimester termination of pregnancy

BACKGROUND

With the improvement of ultrasound technology, the likelihood of detection of major fetal structural anomalies in mid-pregnancy has increased considerably. Upon the detection of serious anomalies, women typically are offered the option of pregnancy termination. Additionally, there are still many reasons other than fetal anomalies why women seek abortion in the mid-trimester.

OBJECTIVES

To compare different methods of second trimester medical termination of pregnancy for their efficacy and side-effects.

SEARCH STRATEGY

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library), MEDLINE, Popline and reference lists of retrieved papers and other sources.

SELECTION CRITERIA

All randomised controlled trials (RCTs) examining medical regimens for termination of pregnancy of a singleton living fetus between 12-28 weeks' gestation were analysed. The outcome measures were the induction to abortion interval, abortion rate within 24 hours, need for surgical evacuation, blood loss, uterine rupture, pain, and side-effects.Trials including >20% fetal death, multiple pregnancies, previous uterine scars and regimens which involved cervical preparation were excluded.

DATA COLLECTION AND ANALYSIS

Two authors selected the trials and three authors extracted data.

MAIN RESULTS

Fourty RCTs were included, addressing various agents for pregnancy termination and methods of administration. When used alone, misoprostol was an effective inductive agent, though it appeared to be more effective in combination with mifepristone. However, the evidence from RCTs is limited.Misoprostol was preferably administered vaginally, although among multiparous women sublingual administration appeared equally effective. A range of doses of vaginally administered misoprostol has been used. No randomised trials comparing doses of misoprostol were identified; however low doses of misoprostol appear to be associated with fewer side-effects while moderate doses appear to be more efficient in completing abortion. Four RCTs showed that the induction to abortion interval with 3-hourly vaginal administration of prostaglandins is shorter than 6-hourly administration without an increase in side-effects.Many studies reported the need for surgical evacuation. Indications for surgical evacuation include retained products of the placenta and heavy vaginal bleeding. Fewer women required surgical evacuation when misoprostol was administrated vaginally compared with women receiving intra-amniotical PGF(2a) . Mild, self-limiting diarrhoea was more common among women who received misoprostol compared to other agents.

AUTHORS' CONCLUSIONS

Medical abortion in the second trimester using the combination of mifepristone and misoprostol appeared to have the highest efficacy and shortest abortion time interval. Where mifepristone is not available, misoprostol alone is a reasonable alternative. The optimal route for administering misoprostol is vaginally, preferably using tablets at 3-hourly intervals. Apart from pain, the side-effects of vaginal misoprostol are usually mild and self limiting. Conclusions from this review are limited by the gestational age ranges and variable medical regimens, including dosing, administrative routes and intervals of medication, of the included trials.

Intervention rates for placental removal following induction abortion with misoprostol

BACKGROUND

Second-trimester terminations can be performed via surgical or medical methods. It is essential to have the ability to safely and effectively perform induction terminations to offer a full range of services. Many studies of induction abortions report routine operative removal of the placenta after a set time period resulting in high rates of operative procedures.

STUDY DESIGN

A retrospective chart review was performed for 233 women who underwent second-trimester induction abortions between November 2003 and November 2006. All women received intraamniotic injection of digoxin for feticide 1 day prior to induction. All inductions were performed using a schedule of 400 mcg of misoprostol initially followed by 200 mcg every 6 h for a maximum of 48 h. There were three methods of administering misoprostol: (1) vaginal administration for all doses, (2) vaginal and buccal used in combination and (3) buccal for all doses. Spontaneous expulsion of the placenta was expected. Operative intervention was performed for excessive bleeding or to expedite hospital discharge after a minimum of 4 h. No manual removal of placenta was done.

RESULTS

The rate of operative intervention for retained placentas was 6% (14/233). Most (11/14) of the patients who underwent operative extraction for retained placentas did so to expedite discharge from the hospital. Overall, expectant management to allow spontaneous expulsion of the placenta for at least 4 h was not associated with serious morbidity.

CONCLUSIONS

Our regimen of digoxin and misoprostol with a policy of expectant management of placental passage is associated with a very low rate of instrumented removal of the placenta. In the absence of bleeding, patients may be afforded intervals to at least 4 h for spontaneous expulsion of the placenta after fetal expulsion.

High-dose vaginal misoprostol versus concentrated oxytocin plus low-dose vaginal misoprostol for midtrimester labor induction: a randomized trial

OBJECTIVE

This study was undertaken to compare the efficacy and side effects of a high-dose vaginal misoprostol regimen to concentrated intravenous oxytocin plus low-dose vaginal misoprostol for midtrimester labor induction.

STUDY DESIGN

Women at 14 to 24 weeks, with obstetric or fetal indications for delivery and no prior cesarean, were randomly assigned to receive either vaginal misoprostol 600 microg x 1, then 400 microg every 4 hours x 5 (group 1) or escalating dose-concentrated oxytocin infusions (277-1667 mU/min) plus vaginal misoprostol 400 microg x 1, then 200 microg every 6 hours x 2, then 100 microg x 1 (group 2). Analysis was by intent to treat. Primary outcomes were live birth rate and induction-to-delivery interval.

RESULTS

The intended sample size was 70 women per group; however, the trial was terminated at the initial interim analysis because of a highly significant difference in 1 of the primary study outcomes. Twenty women were assigned to group 1 and 18 were assigned to group 2. Median induction-to-delivery interval was significantly shorter in group 1 (12 hours, range 4-44 hours) versus group 2 (18 hours, range 7-36 hours; P = .01). Induction success rate at 12 hours was significantly higher in group 1 (60%) compared with group 2 (22%, P = .02). No significant difference was noted in the live birth rate between groups 1 and 2 (13%, 0%, P = .16). The incidence of retained placenta requiring curettage, chorioamnionitis, intrapartum fever, nausea, emesis, and diarrhea were similar between both groups.

CONCLUSION

Compared with concentrated oxytocin plus low-dose vaginal misoprostol, high-dose vaginal misoprostol significantly shortens midtrimester labor inductions.

Vaginal misoprostol versus concentrated oxytocin and vaginal PGE2 for second-trimester labor induction

OBJECTIVE

To compare the efficacy, side effects, and complications of high-dose vaginal misoprostol with concentrated intravenous oxytocin plus low-dose vaginal prostaglandin (PGE(2)) for second-trimester labor induction.

METHODS

One hundred twenty-six consenting women with maternal or fetal indications for pregnancy termination and no prior cesarean delivery were randomly assigned to receive either vaginal misoprostol 600 microg 1x, 400 microg every 4 hours 5x (misoprostol group, n = 60) or escalating-dose concentrated oxytocin infusions (277-1,667 mU/min) plus vaginal PGE(2) 10 mg every 6 hours 4x (oxytocin group, n = 66). Both groups received concurrent extra-amniotic saline infusion for cervical ripening. Women who failed their assigned regimen received 20 mg of PGE(2) suppositories every 4 hours until delivery. Analysis was by intent to treat.

RESULTS

Demographic characteristics were similar between study groups. Median induction-to-delivery interval was significantly shorter in the misoprostol group (12 hours) than in the oxytocin group (17 hours; P <.001). There was a higher induction success rate at 24 hours in the misoprostol group (95%) than in the oxytocin group (85%; P =.06), although this difference did not reach statistical significance. The incidence of live birth (25% versus 17%), chorioamnionitis (5% versus 2%), and postpartum hemorrhage greater than 500 mL (3% versus 3%) were similar between the misoprostol and oxytocin groups, respectively. Diarrhea (2% versus 11%; P =.04), nausea/emesis (25% versus 42%; P =.04), and retained placenta requiring curettage (2% versus 15%; P =.008) were significantly less common in the misoprostol group when compared with the oxytocin group, respectively. Isolated intrapartum fever, however, was more frequent in the misoprostol group (67%) than in the oxytocin group (21%; P <.001).

CONCLUSION

Compared with concentrated oxytocin plus low-dose vaginal PGE(2), high-dose vaginal misoprostol is associated with significantly shorter induction-to-delivery intervals, fewer side effects, a lower incidence of retained placenta, and comparable incidence of live birth.

Methods for Induced Abortion

We describe present methods for induced abortion used in the United States. The most common procedure is first-trimester vacuum curettage. Analgesia is usually provided with a paracervical block and is not completely effective. Pretreatment with nonsteroidal analgesics and conscious sedation augment analgesia but only to a modest extent. Cervical dilation is accomplished with conventional tapered dilators, hygroscopic dilators, or misoprostol. Manual vacuum curettage is as safe and effective as the electric uterine aspirator for procedures through 10 weeks of gestation. Common complications and their management are presented. Early abortion with mifepristone/misoprostol combinations is replacing some surgical abortions. Two mifepristone/misoprostol regimens are used. The rare serious complications of medical abortion are described. Twelve percent of abortions are performed in the second trimester, the majority of these by dilation and evacuation (D&E) after laminaria dilation of the cervix. Uterine evacuation is accomplished with heavy ovum forceps augmented by 14-16 mm vacuum cannula systems. Cervical injection of dilute vasopressin reduces blood loss. Operative ultrasonography is reported to reduce perforation risk of D&E. Dilation and evacuation procedures have evolved to include intact D&E and combination methods for more advanced gestations. Vaginal misoprostol is as effective as dinoprostone for second-trimester labor-induction abortion and appears to be replacing older methods. Mifepristone/misoprostol combinations appear more effective than misoprostol alone. Uterine rupture has been reported in women with uterine scars with misoprostol abortion in the second trimester. Fetal intracardiac injection to reduce multiple pregnancies or selectively abort an anomalous twin is accepted therapy. Outcomes for the remaining pregnancy have improved with experience.

Laminaria versus extra-amniotic saline solution infusion for cervical ripening in second-trimester labor inductions

OBJECTIVE

The aim of this study was to determine which cervical ripening method, laminaria placement or extra-amniotic saline solution infusion, was associated with the shorter interval from induction to delivery in the second trimester.

STUDY DESIGN

Women admitted for indicated second-trimester labor induction with an unfavorable cervix were randomly assigned to receive either intracervical placement of laminaria (n = 25) or extra-amniotic saline solution infusion (n = 25) with concurrent concentrated oxytocin and vaginally administered prostaglandin E2 (10 mg every 6 hours). Treatment success was defined as an interval from induction to delivery of < or =24 hours.

RESULTS

Maternal age, race, parity, gestational age, and initial cervical dilatation were similar between the groups. Indications for uterine evacuation were also similar and included fetal death (n = 7), aneuploidy (n = 20), fetal structural anomaly (n = 18), and maternal indications (n = 4). There was no difference in the mean intervals from induction to delivery (laminaria, 16 +/- 8 hours, vs extra-amniotic saline solution infusion, 17 +/- 10 hours) or the number of treatment successes (laminaria, n = 23, vs extra-amniotic saline solution infusion, n = 21). Retained placenta, live birth, and hemorrhage occurred with similar frequencies in the two groups.

CONCLUSION

Relative to laminaria, extra-amniotic saline solution infusion did not shorten the induction-to-delivery interval in women undergoing indicated second-trimester labor induction with concentrated oxytocin and low-dose vaginally administered prostaglandin E2.

Uterine curettage following second trimester abortion by extraovular instillation of prostaglandin E2. A prospective-randomized trial

OBJECTIVE

To evaluate the benefits associated with routine uterine curettage following complete second trimester termination of pregnancy by extraovular prostaglandin E2.

STUDY DESIGN

Fifty-five patients between 15 and 24 weeks' gestation who had undergone complete termination of pregnancy by continuous extraovular instillation of prostaglandin E2 (PGE2), were randomly assigned into either no further intervention (n=25), or uterine curettage under general anesthesia (n=30). The need for late uterine curettage, clinical and ultrasonographic parameters at 1 and 42 days follow-up, as well as the incidence of the minor and major complications, were compared between groups.

RESULTS

Baseline and post-abortion clinical and ultrasonographic characteristics were similar in both groups. Mean (+/- Standard error of the mean) number of post-abortion bleeding days in the curettage group was 8.9+/-1.8 versus 10.1+/-2.6 days in the non-curettage group (P=NS). No patient in the former group, compared to three patients in the latter group, needed late uterine curettage, (P=NS). Major and minor complications rates in the curettage and in the no-curettage groups were not significantly different. Considerably more patients in the curettage group needed analgesic agents following the abortion compared to the no-curettage group (60% vs. 3.3%, respectively; P<0.001).

CONCLUSIONS

Routine uterine curettage in patients undergoing complete second trimester termination of pregnancy by extraovular instillation of PGE2, exerts no benefit.

Vaginal misoprostol vs. concentrated oxytocin plus low-dose prostaglandin E2 for second trimester pregnancy termination

OBJECTIVE

To examine the efficacy of vaginal misoprostol for mid-trimester pregnancy termination.

METHODS

This randomized trial compared misoprostol, 200 microg per vaginum q 12 h to a protocol of concentrated oxytocin plus low-dose vaginal prostaglandin E2 suppositories (10 mg q 6 h). Success was defined as an induction-to-delivery interval < or =24 h.

RESULTS

Interim analysis of the first 30 (15-misoprostol, 15-concentrated oxytocin) women demonstrated that the 2 groups were similar with regard to indication for delivery, gestational age, and demographic characteristics. Misoprostol was associated with a lower success rate (67 vs. 87%, P = .2), a longer induction-delivery interval (22 h vs. 18 h, P = .09), a higher rate of retained placenta requiring curettage (27 vs. 13%, P = .65), and a higher live birth rate (50 vs. 0%, P = .006).

CONCLUSIONS

Compared to a regimen of concentrated oxytocin plus low-dose prostaglandin E2, misoprostol administered as vaginal tablets in a dose of 200 microg q 12 h is not satisfactory for mid-trimester pregnancy termination in an unselected population.