Abortion after 24 0/7 weeks of gestation

INTRODUCTION — Abortion after 24 0/7 weeks of gestation is uncommon. Like abortions performed at earlier gestations, abortions after 24 0/7 weeks can be performed surgically, with dilation and evacuation (D&E), or with medication (also termed medication abortion or induction abortion). While research on abortion after 24 0/7 weeks is limited, much of the literature on second-trimester abortion also applies to third-trimester abortion.

This topic will focus on the differences in epidemiology, counseling, protocols, and outcomes for abortion after 24 0/7 weeks. An overview of pregnancy termination, general abortion counseling, first- and second-trimester pregnancy termination, cervical preparation for procedural abortion, induced fetal demise, and unsafe abortion are discussed elsewhere.

●(See "Overview of pregnancy termination".)

●(See "First-trimester pregnancy termination: Medication abortion" and "First-trimester pregnancy termination: Uterine aspiration".)

●(See "Overview of second-trimester pregnancy termination" and "Second-trimester pregnancy termination: Induction (medication) termination" and "Second-trimester pregnancy termination: Dilation and evacuation".)

●(See "Pregnancy termination: Cervical preparation for procedural abortion".)

●(See "Induced fetal demise".)

●(See "Unsafe abortion".)

●(See "Counseling in abortion care".)

DEFINITIONS — In this topic, we use the phrase "abortion later in pregnancy" to describe abortion after 24 0/7 weeks of gestation. However, other definitions have been described [1], and the American College of Obstetricians and Gynecologists (ACOG) defines second-trimester abortion as abortion up to 26 weeks of gestation (as calculated from the last menstrual period) [2].

In the United States, terminology around abortion in the third trimester is often biased by political rhetoric. Phrases like "late-term abortion" or "partial-birth abortion" are sometimes used in reference to abortion at these gestations. However, these terms are nonmedical phrases created to perpetuate stigma and antiabortion sentiment, and ACOG states that these phrases should not be used [1]. Rather, "late term" can be used to refer to term pregnancies (outside of the context of abortion) between 41 weeks and 41 6/7 weeks gestation. (See "Postterm pregnancy" and "Postterm pregnancy", section on 'Classification of term gestations'.)

EPIDEMIOLOGY — Abortions after 24 0/7 weeks account for a very small percentage of all abortions sought or completed. According to data from the Centers for Disease Control and Prevention (CDC), about 1.3 percent of abortions in the United States are performed at 21 weeks of gestation or later. The CDC does not provide more specific incidence information about abortion later than 24 0/7 weeks of gestation. Worldwide, in countries in which abortion is legal, some data show an even lower incidence of abortions completed after 24 0/7 weeks [3,4].

However, the complex and varying legal and sociopolitical contexts for abortion internationally lead to a lack of documentation and consequently a lack of data. It is thus difficult to truly quantify the number of patients receiving abortion later in pregnancy in both the United States and abroad.

Characteristics — As abortion after 24 0/7 weeks is uncommon, it is difficult to ascertain characteristics of those who seek abortion at these gestational ages. Additionally, research does not always distinguish between second- and third-trimester abortion care. Factors that may be associated with abortion later in pregnancy include the following:

●Younger age [5].

●Lower levels of education and income [6].

●Higher rates of life stressors (eg, partner separation, unemployment, intimate partner violence) [5,6].

●Logistical delays (eg, financial, medical, social, or geographic barriers) [5,6]. In one analysis of abortions in the United States, patients were more likely to undergo a second-trimester abortion if they lived ≥50 compared with <25 miles from an abortion clinic [6]. This study did not differentiate between those receiving abortion care at 13 to 24 weeks from those receiving an abortion after 24 0/7 weeks.

●Estimation of last menstrual period, rather than knowing last menstrual period with certainty [7]. Finding out "late" about pregnancy is one pathway to abortion at later gestational ages [8].

Restrictive legal environments — Abortion restrictions are prevalent in many jurisdictions, resulting in delays in accessing abortion care and an increase in abortions at later gestations [9].

In settings where abortion is legal after 24 0/7 weeks of gestation in the United States, access is contingent upon the availability of appropriately trained clinicians, the existence of actively operating and accredited clinics or hospitals that offer this care within their Obstetrics and Gynecology or Complex Family Planning departments, and support by their institutional policies. Availability of care can be impacted by changes, limitations, or restrictions to any one of these factors. Other legal issues, such as mandatory waiting periods, parental notification or consent, Risk Evaluation and Mitigation Strategy (REMS) restrictions for mifepristone, and assessment of fetal viability, are discussed in detail separately. (See "Overview of pregnancy termination", section on 'Legal issues' and "Overview of pregnancy termination", section on 'REMS restrictions' and "Periviable birth (limit of viability)", section on 'Definitions'.)

Very few providers in the United States are trained to perform procedural abortion later in pregnancy. The infrequency of abortion at this gestational age results in fewer opportunities for training. Approximately twenty facilities in the United States provide procedural abortion care over 24 0/7 weeks [3]. Only a minority of these facilities provide terminations over 28 weeks of gestation [1]. A list of clinics providing later abortion care in the United States is maintained by the Later Abortion Initiative [10] and discussed below. (See 'Counseling and informed consent' below.)

Clinicians who may need to refer patients for abortion care should familiarize themselves with their local and state abortion laws and maintain an active list of referrals for abortion in all trimesters. A summary of United States abortion laws can be found through the Guttmacher Institute.

INDICATIONS — Patients pursue abortion after 24 0/7 weeks for a diverse set of reasons.

●Maternal indications – Patients seeking abortion after 24 0/7 weeks often do so as a result of a new maternal health diagnosis (eg, severe maternal hypertension with fetal growth restriction and oligohydramnios) or as a result of a changing life circumstance (eg, a new health concern of their partner or intended support person, changes to financial security, changes to the political environment) that affects a person's ability to parent [4,5].

In one cohort study of 272 patients who had obtained an abortion at ≥20 weeks of gestation, most fit into one of the following five categories: those experiencing domestic or intimate partner violence; those who were young and nulliparous; those who were already parents and raising children alone; those who were experiencing depression or substance use disorders; and those who had pregnancy ambivalence and later experienced barriers to abortion care [5].

In a subsequent cohort study of 28 patients who received an abortion at ≥24 0/7 weeks of gestation, two common pathways were identified which led patients to obtain a third-trimester abortion [8]:

•Receiving new information (eg, finding out that they were pregnant when they had previously thought they were not, finding out they themselves had a health problem due to pregnancy) that made them no longer want to continue the pregnancy.

•Facing significant barriers (eg, funding the procedure, stigmatization, finding a provider who could perform the abortion) to a long-desired abortion which led to a significant delay between making the choice to have an abortion and the abortion procedure.

●Fetal indications – Patients seeking abortion after 24 0/7 weeks may also do so because of a new fetal diagnosis (eg, complex fetal central nervous system anomaly) [4,8]. Though newer technologies enable the identification of some chromosomal anomalies early in pregnancy, many patients do not find out about structural malformations and other anomalies until the second or third trimester [11].

Additionally, though some diagnoses may be identified early in pregnancy, subsequent testing and consultations with multiple physician experts can delay a patient's choice to terminate and their ability to schedule care. Obstetrician-gynecologists and maternal fetal medicine (MFM) subspecialists should be aware that increasingly limited access to abortion after 24 0/7 weeks may be an important factor to address in counseling after a suspected or confirmed fetal diagnosis.

More discussion of fetal anomalies can be found elsewhere. (See "Congenital anomalies: Approach to evaluation" and "Congenital anomalies: Epidemiology, types, and patterns".)

PREPROCEDURE PLANNING

Counseling and informed consent — Patients considering abortion after 24 0/7 weeks gestation should be counseled regarding the decision to terminate or continue the pregnancy and the procedural and medical options for termination. Patients should be counseled about follow-up care, contraception, methods to suppress lactation, and potential complications of the procedure. This discussion should be documented on the procedure consent form and in the medical record. (See "Counseling in abortion care" and "Overview of pregnancy termination", section on 'Counseling and informed consent' and "Overview of second-trimester pregnancy termination", section on 'Postprocedure considerations'.)

Such patients may also have a particularly complex set of circumstances or face additional barriers and stigma that can make the counseling process particularly beneficial, such as:

●The need to travel long distances and related additional logistical barriers. Availability of abortion at this stage is limited and most patients will have to travel for care. Living farther from accessible abortion is associated with lower likelihoods of obtaining abortion care [12]. Patients may require counseling on the need for multiday stays at or near the location of their procedure and the associated potential needs for childcare, time off work, and costs associated with meals and travel. Counseling regarding support for travel can be provided by staff at the clinic where the patient will receive care or by organizational resources and relevant hotlines, such as the National Abortion Hotline in the United States which can help patients navigate and coordinate care. A list of clinics providing later abortion care in the United States is maintained by the Later Abortion Initiative [10]. Referring clinicians may engage in counseling as they see fit given their knowledge and legal context.

●Patients should be cautioned about the significant misinformation and disinformation online and referred to reputable sources for accurate medical information. Clinicians should also familiarize themselves with these resources, which are provided separately. (See "Counseling in abortion care", section on 'Resources'.)

●Increased rates of ambivalence about the pregnancy. In one longitudinal cohort study of 667 patients, those seeking abortion further into pregnancy were shown to have more mixed feelings when their pregnancy was initially planned or when they had more difficulty deciding to have an abortion [13]. However, ambivalence is not unique to abortion, but rather an emotion evoked by many health care decisions. Counseling can aim to use emotional care and decision-making aids to help reduce ambivalence and/or to help patients accept their ambivalence and move forward with a decision [14].

Determining gestational age and other laboratory testing — Determining gestational age is a critical part of providing appropriate care. This is discussed in detail separately. (See "Overview of pregnancy termination", section on 'Determining gestational age'.)

The role of laboratory testing for hemoglobin or hematocrit, Rh typing (and administration of Rh[D] immune globulin to Rh-negative individuals), and chlamydia and/or gonorrhea are also described in detail separately. (See "Overview of pregnancy termination", section on 'Preparation for procedure'.)

Choosing procedure type — As with pregnancies at earlier gestations, the choice between dilation and evacuation (D&E) and medication abortion at later gestational ages depends mainly upon patient preference, existing medical conditions (eg, bleeding diathesis), and the availability of a clinician with the skills and experience to provide one or both approaches. However, in most health care settings, there is more access to medication abortion than D&E due to lack of clinician training and the scarcity of providers who perform such procedures. (See 'Restrictive legal environments' above.)

In our practice, we provide both D&E and medication abortion. When patients have no strong preference or medical reason to choose one method over another, we typically guide patients at ≤26 to 28 weeks of gestation towards D&E, and those at >26 to 28 weeks of gestation toward medication abortion. Gestational age dating in this context may be based on ultrasound measurements, although most literature bases choice of procedure type on weeks from last menstrual period [15].

The advantages and disadvantages of each procedure are discussed separately. (See "Overview of second-trimester pregnancy termination", section on 'Choosing dilation and evacuation versus induction termination'.)

DILATION AND EVACUATION

Preprocedural preparation

Cervical preparation — Cervical preparation is performed prior to dilation and evacuation (D&E) as it decreases the risk of cervical laceration and hemorrhage [16]. Options for cervical preparation, including osmotic dilators (ie, laminaria japonica, Dilapan-S) and pharmacologic methods (eg, mifepristone and misoprostol), and how to perform this procedure are discussed in detail separately. (See "Pregnancy termination: Cervical preparation for procedural abortion".)

Cervical preparation for procedures after 24 0/7 weeks may require additional dilation than procedures prior to 24 0/7 weeks gestation (see "Pregnancy termination: Cervical preparation for procedural abortion", section on '≥18 weeks'); however, data are limited. Our protocol varies based on gestational age:

●For patients at 24 to 26 weeks, we often follow a three-day protocol:

•Day 1 – Mifepristone 200 mg orally after an injection to induce fetal demise. (See 'Injection to induce fetal demise' below.)

•Day 2 – Dilators (eg, four Dilapan-S and two laminaria) are placed.

•Day 3 – Misoprostol 400 mcg (or 200 mcg in patients with prior cesarean birth) is administered vaginally, followed by D&E. As in the two-day protocol, in patients with adequate dilation, misoprostol may be omitted.

Another three-day protocol has also been described. On day 1, one to four laminaria are placed, followed by 4 to 20 laminaria in one or two sittings on day 2, and performance of the abortion on day 3. On day 3, the membranes are ruptured followed by D&E [17].

●At later gestational ages (ie, after 26 weeks but typically less than 27 weeks), additional doses of misoprostol or an intrauterine foley catheter may be required to achieve adequate dilation.

Injection to induce fetal demise — In our practice, we induce fetal demise prior to D&E after 24 0/7 weeks gestation. However, practice varies, and other experts do not perform feticidal injection prior to D&E. The rationale for induction of fetal demise is discussed elsewhere, as is the technique and choice of agents. (See "Induced fetal demise".)

Anesthesia — Third-trimester D&E is typically performed using a paracervical block and intravenous conscious sedation. Anesthesia for office procedures and the paracervical block technique are described elsewhere. (See "Office-based anesthesia" and "Pudendal and paracervical block", section on 'Paracervical block'.).

The Society of Family Planning (SFP) also provides guidelines for moderate and deep sedation and general anesthesia for abortion [18].

Prophylactic antibiotics — Prophylactic antibiotics are administered prior to D&E to decrease the rate of infection. The evidence supporting antibiotic prophylaxis prior to procedural abortion is presented separately. (See "First-trimester pregnancy termination: Uterine aspiration", section on 'Antibiotic prophylaxis' and "Pregnancy termination: Cervical preparation for procedural abortion", section on 'Procedure'.)

One of our contributors (JR) administers a single dose of azithromycin 500 mg orally at time of dilator placement plus ceftriaxone 500 mg (1 g in patients ≥150 kg) intravenously at the time of D&E procedure. Azithromycin is generally well tolerated, and ceftriaxone provides additional coverage for gonococcal infection. However, practice varies, and other experts use azithromycin monotherapy (with a second dose of azithromycin if the surgical abortion is performed >24 hours after the initial dose of antibiotics) or doxycycline monotherapy as a single dose prior to uterine evacuation. This is summarized in the table (table 1).

Uterine evacuation — Our protocol for D&E from 24 to 26 weeks of gestation is similar to that described for second-trimester D&E (see "Second-trimester pregnancy termination: Dilation and evacuation"), with the following modifications:

●Speculum – We typically use either a Klopfer or Moore-Graves speculum, which are both shorter than a Graves or Pederson speculum and less obstructive of the vaginal vault, allowing for better visualization and easier removal of pregnancy tissue.

●Cervical dilation – For procedures later in gestation, dilation of 2 to 3 centimeters is typically easily achieved with cervical preparation (see 'Cervical preparation' above). Forceps should easily pass through the cervix without resistance and additional mechanical dilation is usually not required.

The role of mechanical cervical dilation, should it be needed, is described separately. (See "Pregnancy termination: Cervical preparation for procedural abortion", section on 'Role of mechanical dilation'.)

●Uterine evacuation – Using intraoperative ultrasound guidance, amniotomy is performed with the suction cannula, and the fetus and placenta are removed with forceps (eg, Blumenthal, Bierer, Hern, Sopher) (picture 1 and picture 2). Suction is then used at the conclusion of the procedure to ensure all tissue has been removed.

Techniques that facilitate the procedure and help to avoid complications are described elsewhere. (See "Second-trimester pregnancy termination: Dilation and evacuation", section on 'Uterine evacuation'.)

●Uterotonic and vasoconstrictive agents – As the risk of hemorrhage in D&E increases with gestational age, we use a vasoconstrictor (eg, vasopressin 4 to 6 units) in the paracervical block as well as intravenous oxytocin (eg, 20 units in 500 mL 0.9 percent saline administered over 60 minutes) at the conclusion of the procedure. However, the routine use of perioperative or postoperative uterotonic agents is a subject of debate, and there is limited evidence to support this approach. In addition, the SFP guidelines do not recommend use of hemorrhage prophylaxis in second-trimester D&E. This is discussed in detail separately. (See "Second-trimester pregnancy termination: Dilation and evacuation", section on 'Use of uterotonics and vasoconstrictive agents'.)

●Assessment for retained products of conception – At the conclusion of the procedure, we use transabdominal ultrasound to assess for retained products of conception. The surgeon should also inventory the evacuated contents and account for the major fetal parts (calvaria, thorax, pelvis, four extremities). (See "Second-trimester pregnancy termination: Dilation and evacuation", section on 'Assessment for retained products of conception'.)

MEDICATION ABORTION — Medication abortion involves the administration of medication through one of a variety of routes to induce labor and deliver the fetus. Expert guidance varies, and the recommendations presented here are largely based on expert opinion and guidance from the Society of Family Planning.

Medical induction of labor for intrauterine fetal death after 24 0/7 weeks is discussed separately. (See "Stillbirth: Maternal care and prognosis", section on 'Fetal death after approximately 24 weeks'.)

Preprocedure preparation

Cervical preparation — In our practice, we place osmotic dilators (ie, laminaria, Dilapan-S) on day 2 of a three-day protocol (see 'Protocols' below):

●Day 1 – Mifepristone is administered

●Day 2 – Osmotic dilators are placed

●Day 3 – Misoprostol is administered. If dilation is found to be inadequate on day 3, a foley catheter can be inserted for additional mechanical dilation.

Although cervical preparation with osmotic dilators prior to medication abortion in the second trimester has not been demonstrated to offer benefit [19,20] (see "Second-trimester pregnancy termination: Induction (medication) termination"), some data support the use of osmotic dilators at later gestations [17,21,22]. Limitations in these studies (eg, not describing the effect of dilation by gestational age, including patients under 24 0/7 weeks of gestation, not reporting complications or induction-to-delivery times) make it difficult to ascertain the impact of osmotic dilators in this population.

In a retrospective study of 491 patients at ≥14 weeks of gestation undergoing medication abortion with mifepristone and misoprostol, those also receiving osmotic dilators (Dilapan-S) compared with no osmotic dilators had a shorter induction-to-delivery time (428 versus 640 minutes); median gestational age was 23 weeks in the dilator group and 25 weeks in the group without dilators [23]. However, after 28 weeks of gestation, the induction-to-delivery time was reduced by only 20 minutes. In another cohort study including 174 patients between 18 and 30 weeks of gestation undergoing medication abortion with mifepristone and misoprostol, those receiving osmotic dilators (laminaria) compared with no osmotic dilators had a shorter induction-to-delivery time (7.5 versus 12.7 hours) [24]. While the impact of laminaria appeared to decrease with increasing gestational age, the authors did not provide the details of this potential effect. By contrast, in a randomized trial of 347 patients between 15 0/7 and 27 6/7 weeks of gestation, those receiving cervical preparation plus misoprostol compared with misoprostol alone had similar induction-to-delivery times [25]. This is also discussed separately. (See "Second-trimester pregnancy termination: Induction (medication) termination".)

Cervical ripening with a foley catheter has also been described. In a retrospective study of over 100 patients at ≥28 weeks of gestation with an intrauterine fetal demise or pregnancy termination and undergoing induction of labor, those receiving a foley catheter plus oxytocin compared with a vaginal prostaglandin experienced shorter induction-to-delivery times (17 versus 39 hours) [26]. The foley catheter was used more often in patients with a prior cesarean birth.

Injection to induce fetal demise — Inducing fetal demise prior to abortion may be performed to either facilitate the abortion procedure or to prevent live birth. Induced fetal demise, as well as the technique and choice of agents, is discussed in detail separately.

In our practice, we induce fetal demise prior to medication abortion after 24 0/7 weeks gestation. For such cases, we perform an injection of 1% lidocaine (20 to 24 mL) into the fetal cardiac chamber on day 1 of a three-day procedure. Other methods to induce fetal demise are effective. (See "Induced fetal demise".)

Anesthesia — Patients undergoing medication abortion can receive systemic (eg, opioid), regional (eg, epidural) analgesia, and/or local anesthesia (eg, paracervical block), which is similar to patients undergoing obstetric labor induction, and is discussed in detail separately. (See "Pharmacologic management of pain during labor and delivery" and "Pudendal and paracervical block".)

It is important to remember that medication abortion is typically a more rapid process than labor induction at term with a viable fetus. (See 'Our practice' below.)

The Society of Family Planning (SFP) also provides recommendations for moderate sedation, deep sedation, and general anesthesia for abortion [18].

Prophylactic antibiotics — Prophylactic antibiotics are typically administered at the time of dilator placement (table 1). (See "Pregnancy termination: Cervical preparation for procedural abortion", section on 'Procedure'.)

Protocols — Protocols for third-trimester medication abortion typically utilize mifepristone and misoprostol; protocols utilizing misoprostol-only and/or oxytocin have also been described. (See 'Other techniques' below.)

Our practice — In our practice, our typical protocol is as follows; modifications may be a necessary for some patients (eg, parous, younger) in whom there is a concern for preterm labor, spontaneous rupture of membranes, infection, or extramural birth:

●Day 1: Mifepristone 200 mg, orally.

●Day 2: Cervical dilators. As an example, four Dilapan-S and two laminaria (diameters vary) may be placed, though other combinations can be used. (See "Pregnancy termination: Cervical preparation for procedural abortion", section on 'Types'.)

●Day 3: Misoprostol 400 mcg (or 200 mcg for patients with a uterine scar) vaginally, placed by the patient one hour prior to arrival. After admission, a paracervical block is performed (see 'Anesthesia' above), followed by amniotomy (eg, with amnio hook, DuPont cannula). If amniotomy cannot be performed, a foley catheter can be inserted for additional mechanical dilation. (See 'Cervical preparation' above.)

An additional dose of misoprostol is placed vaginally at the time of amniotomy, followed by misoprostol (vaginal or buccal) every two hours until delivery. After four to five doses (1600 to 2000 mcg; or 800 to 1000 mcg for patients with uterine scar), the regimen may be switched to oxytocin if delivery is not imminent (see 'Other techniques' below). However, continued use of misoprostol beyond five doses at earlier gestational ages has been described [27,28]. In our experience, most patients between 27 and 32 weeks of gestation deliver within three to four hours of amniotomy.

Decompression of the fetal calvarium may be performed on a case-by-case basis to help ease delivery and prevent perineal lacerations.

●After delivery of the fetus, we await either spontaneous delivery of the placenta or gently use forceps to achieve removal. After removal, suction curettage may be performed to ensure complete evacuation of the uterus. This may be particularly useful in patients who have travelled long distances and in whom follow-up care (eg, for subsequent heavy bleeding, retained products of conception) is often limited.

Other protocols — Other protocols for third-trimester medication abortion include:

●The American College of Obstetricians and Gynecologists (ACOG) protocol for medication abortion up to 26 weeks is provided separately. (See "Second-trimester pregnancy termination: Induction (medication) termination", section on 'Medical society protocols'.)

●The SFP combination protocol for medication abortion between 24 to 28 weeks of gestation is as follows [29,30]:

•Mifepristone 200 mg orally

•After 36 to 48 hours, administer misoprostol 200 to 400 mcg vaginally or buccally every three hours. The lower dose (200 mcg) should be used in patients with a uterine scar.

The SFP also provides a misoprostol-only protocol [30].

●One retrospective study of 257 patients at ≥24 0/7 weeks undergoing medication abortion with mifepristone and misoprostol described the following protocol [22]. All patients received mifepristone 200 mg orally 24 to 72 hours prior to misoprostol administration; all patients also received feticidal injection and laminaria.

For patients without a uterine scar at:

•<32 weeks: Misoprostol 400 mcg buccally every two hours

•32 weeks: Misoprostol 200 mcg buccally at induction initiation, followed by 400 mcg buccally every two hours if no contractions, and 200 mcg buccally every two hours if uterine contractions are present

•≥33 weeks: Misoprostol 100 to 200 mcg buccally every two hours

For patients with a uterine scar:

•≤26 weeks: Misoprostol 400 mcg buccally followed by 200 mcg buccally every four hours

•27 to 31 weeks: Misoprostol 100 mcg buccally followed by 50 mcg buccally every four hours

In this study, medication abortion was not performed for patients at ≥32 weeks of gestation with a uterine scar given the concern for uterine rupture.

Routes of misoprostol in these protocols vary; studies evaluating routes of misoprostol in patients over 24 0/7 weeks of gestation and limited, and those that do include small numbers of patients. From these studies, we can conclude that vaginal compared with oral misoprostol may be more effective at later gestational ages [31,32], and sublingual and buccal routes also appear to be effective [33]. General principles of the dose, route of administration, and timing of misoprostol are discussed in detail separately. (See "Misoprostol as a single agent for medical termination of pregnancy", section on 'Drug administration' and "First-trimester pregnancy termination: Medication abortion", section on 'Misoprostol'.)

Role of mifepristone — As with medication abortion at earlier gestational ages, mifepristone is often used in combination with misoprostol to improve success rates of medication abortion at later gestational ages. (See "Second-trimester pregnancy termination: Induction (medication) termination".)

In a systematic review of randomized trials including patients undergoing pregnancy termination between 12 and 28 weeks of gestation, combination mifepristone plus misoprostol compared with misoprostol-alone resulted in lower rates of ongoing pregnancy at 24 and 48 hours [31]. A one- to two-day delay between mifepristone and misoprostol (rather than simultaneous dosing) and dosing of misoprostol every three hours also improved efficacy. The study was not able to conclude which route (buccal, sublingual, vaginal) of misoprostol was superior, nor perform subanalyses for different gestational age groups. In a subsequent randomized trial of 66 patients with fetal demise between 14 and 28 weeks of gestation undergoing induction of labor, those treated with mifepristone plus misoprostol compared with misoprostol alone had a shorter time to delivery (6.8 versus 10.5 hours) [34]. Similarly, in a retrospective study including 91 patients with fetal demise >26 weeks of gestation, the addition of mifepristone to misoprostol decreased induction time by 6.5 hours (16.3 to 9.8 hours) [35]. The effect of mifepristone did not seem to vary among those with gestational ages <20 compared with ≥20 weeks (24 patients); however, the study was not powered to detect such a difference.

However, data are conflicting. In a retrospective study of 130 patients undergoing induction of labor for fetal demise at 21 to 42 weeks of gestation, those treated with mifepristone plus misoprostol compared with misoprostol alone had similar induction to delivery times [36]. In another retrospective study that included patients ≥24 0/7 weeks undergoing medication abortion and discussed above (see 'Other protocols' above), the addition of mifepristone to misoprostol did not decrease the induction interval [22]. However, those who received mifepristone 24 to 48 hours prior to induction were less likely to require two days of laminaria and required a lower dose of misoprostol.

Other techniques

●Misoprostol-only – Misoprostol as a single agent for medical termination of pregnancy is discussed separately. (See "Misoprostol as a single agent for medical termination of pregnancy".)

●Oxytocin – In our practice, we utilize oxytocin when the patient has received more than four to five doses (1600 to 2000 mcg; 800 to 1000 mcg for patients with uterine scar) of misoprostol (see 'Our practice' above). However, some experts use oxytocin as the agent of choice for patients with a prior uterine scar. (See "Stillbirth: Maternal care and prognosis", section on 'Fetal death after approximately 24 weeks'.)

In one study including patients undergoing third-trimester medication abortion, laminaria and amniotomy were followed by an intravenous infusion of oxytocin at 10 units/hour [17].

The use of oxytocin for induction of labor at term and for second trimester medical termination is described separately. (See "Induction of labor with oxytocin" and "Second-trimester pregnancy termination: Induction (medication) termination", section on 'Type of prostaglandin'.)

●Amniotomy – Amniotomy has been described in a number of study protocols for third-trimester abortion [17,22], but its impact on induction time is unclear.

COMPLICATIONS — Abortion after 24 0/7 weeks gestation is a safe and effective procedure, but complications can occur. Data are limited as few studies describe complication rates after procedures at such gestational ages; representative studies include the following:

●Overall – In the retrospective study including 54 patients at ≥24 0/7 weeks undergoing medication abortion and discussed above (see 'Other protocols' above), complications occurred in 8.9 percent of patients and included retained placenta (3.3 percent), hemorrhage (1.8 percent), cervical laceration (1.6 percent), hospital transport (1.6 percent), precipitous extramural delivery (1 patient), and death (one patient) [22]. In another retrospective study including 54 patients in the third trimester undergoing medication abortion, 15 patients (28 percent) experienced a complication [37]. However, these studies have several limitations, including that they are retrospective and include only a small number of patients.

●Hemorrhage – In the retrospective study including 54 patients discussed above, the most common complication was blood loss >500 mL (rate of blood loss >500 mL for all patients was 18.3 percent); however, the study also included patients in the first and second trimesters) [37]. Thus, this complication rate should be interpreted carefully.

In another retrospective analysis including 54 abortions performed between 25 and 34 weeks of gestations, disseminated intravascular coagulation occurred in one patient (27 weeks of gestation) and another patient (25 weeks of gestation) experienced blood loss of 1500 mL [17].

●Retained placenta – Retained placenta occurs in approximately 2 to 9 percent of patients undergoing medication abortion after 24 0/7 weeks [35,38]; though higher rates have been reported [24,39,40].

Management of retained placenta is discussed separately. (See 'Our practice' above and "Retained placenta after vaginal birth", section on 'Management'.)

●Uterine rupture – Uterine rupture can occur in patients with a scarred or unscarred uterus. In one retrospective of 111 patients with a prior uterine scar undergoing medication abortion with gemeprost (a prostaglandin; 1 mg every 6 hours) between 14 to 34 weeks of gestation, one uterine rupture was noted in a patient at 26 weeks with two prior cesarean births [38]. In another retrospective study of over 67 patients with a history of cesarean birth undergoing medication abortion (with laminaria, mifepristone, and misoprostol 400 mcg every three hours) between 14 and 37 weeks of gestation, uterine rupture occurred in three (4.8 percent) patients; rupture occurred at 29, 34, and 37 weeks of gestation [21]. In another retrospective study including patients with gestations ≥14 weeks of gestation (mean 23 to 25 weeks) undergoing medication abortion with misoprostol (200 mcg [with a prior uterine scar] or 400 mcg [without a prior uterine scar] every three hours) with or without laminaria, two patients experienced a uterine rupture, one with a history of two prior cesarean births and one with no uterine scar [23]. The gestational age at which rupture occurred was not reported.

Complications after abortions at earlier gestations are described separately. (See "Overview of pregnancy termination", section on 'Complications' and "Second-trimester pregnancy termination: Induction (medication) termination", section on 'Outcome and complications' and "Second-trimester pregnancy termination: Dilation and evacuation", section on 'Outcome and complications'.)

FOLLOW-UP — Follow-up after an abortion after 24 0/7 weeks is similar to that of abortions performed at earlier gestations. In-person follow up is generally not required; rather, we offer phone follow-up the week after their procedure, as most of our patients travel long distances to be seen in our clinic. Patients should be given detailed instructions and should call their provider if they experience any concerns (eg, soaking more than two pads per hour for more than two hours, fever >100.4°F, persistent pelvic or abdominal pain, malodorous discharge). (See "Overview of second-trimester pregnancy termination", section on 'Postprocedure considerations'.)

Contraception options and methods to suppress lactation are also discussed in detail separately. (See "Overview of second-trimester pregnancy termination", section on 'Postprocedure considerations' and "Contraception: Postabortion".)

Grief after termination of pregnancy is a normal reaction, and clinicians must be equipped to support this process for patients, their partners, and their families. A multidisciplinary panel of experts created several principles on global bereavement care after stillbirth, and these may be applied to grief after termination of a desired pregnancy [41]:

●Reducing stigma experienced by families by increasing awareness

●Providing respectful care

●Supporting patients and families to make informed and supported decisions about birth options

●Investigating contributing factors to provide an explanation for the pregnancy outcome

●Acknowledging the depth and variety of normal grief responses

●Enabling the highest quality bereavement care by providing comprehensive training and support to the health care team

Further information about providing support to patients can be found separately. (See "Stillbirth: Maternal care and prognosis", section on 'Helping parents connect with and separate from their child'.)

SOCIETY GUIDELINE LINKS — Links to society and government-sponsored guidelines from selected countries and regions around the world are provided separately. (See "Society guideline links: Pregnancy termination".)

SUMMARY AND RECOMMENDATIONS

●Clinical significance – Abortion after 24 0/7 weeks accounts for a very small percentage of all abortions completed. Like abortions performed at earlier gestations, abortions after 24 0/7 weeks can be performed surgically, with dilation and evacuation (D&E), or with medication (also termed medication abortion or induction abortion). (See 'Introduction' above and 'Epidemiology' above.)

●Indications – Individuals pursue abortion after 24 0/7 weeks for a diverse set of reasons (eg, new maternal health diagnosis, new health or other concern of their partner or intended support person, changes to financial security, new fetal diagnosis). (See 'Indications' above.)

●Choosing procedure type – The choice between D&E and medication abortion depends mainly upon patient preference, existing medical conditions, and the availability of a clinician with the skills and experience to provide one or both approaches. (See 'Choosing procedure type' above.)

●Dilation and evacuation

•Cervical preparation – Cervical preparation with osmotic dilators (ie, laminaria japonica, Dilapan-S) and pharmacologic methods (eg, mifepristone and misoprostol) is performed prior to D&E as it decreases the risk of cervical laceration and hemorrhage. This is discussed in detail separately. (See 'Cervical preparation' above and "Pregnancy termination: Cervical preparation for procedural abortion".)

•Induce fetal demise – In our practice, we induce fetal demise prior to D&E after 24 0/7 weeks gestation. However, practice varies, and other experts do not perform feticidal injection prior to D&E. This is discussed in detail separately. (See 'Injection to induce fetal demise' above and "Induced fetal demise", section on 'Dilation and evacuation'.)

•Prophylactic antibiotics – Antibiotics are administered prior to D&E, as summarized in the table (table 1). The supporting evidence for antibiotic prophylaxis in patients undergoing procedural abortion is discussed separately. (See 'Prophylactic antibiotics' above and "First-trimester pregnancy termination: Uterine aspiration", section on 'Antibiotic prophylaxis'.)

•Uterotonic and vasoconstrictive agents – For most patients undergoing D&E after 24 0/7 weeks gestation, we suggest the use of perioperative or postoperative uterotonic agents (Grade 2C). In our practice, we use vasopressin in the paracervical block as well as an intravenous oxytocin infusion at the conclusion of the procedure. The risk of hemorrhage in D&E increases with increasing gestational age. However, there are limited data to support this approach and the routine use of such agents is a subject of debate. (See 'Uterine evacuation' above.)

●Medication abortion

•Cervical preparation – For most patients undergoing medication abortion after 24 0/7 weeks gestation, we suggest cervical preparation with osmotic dilators (Grade 2C). This differs from medication abortion at earlier gestations where cervical preparation has not been demonstrated to offer benefit. Cervical preparation may shorten induction-to-delivery time, but data are conflicting. (See 'Cervical preparation' above and "Second-trimester pregnancy termination: Induction (medication) termination".)

•Induce fetal demise – We induce fetal demise prior to medication abortion after 24 0/7 weeks gestation. This is discussed in detail separately. (See 'Injection to induce fetal demise' above and "Induced fetal demise", section on 'Medication abortion'.)

•Prophylactic antibiotics – Prophylactic antibiotics are typically administered at the time of dilator placement (table 1). (See 'Prophylactic antibiotics' above and "Pregnancy termination: Cervical preparation for procedural abortion", section on 'Procedure'.)

•Protocol – For patients undergoing medication abortion after 24 0/7 weeks gestation, we suggest use of misoprostol combined with mifepristone, rather than misoprostol alone (Grade 2C). As with medication abortion at earlier gestational ages, mifepristone in combination with misoprostol appears to improve success rates of medication abortion, but studies including patients at later gestational ages are limited. (See 'Our practice' above and 'Role of mifepristone' above.)

●Complications – Abortion after 24 0/7 weeks gestation is a safe and effective procedure, but complications (eg, hemorrhage, retained placenta, uterine rupture) can occur. (See 'Complications' above.)