eMedicine Specialties > Obstetrics and Gynecology > General Gynecology

Therapeutic Abortion

Author: Denise James, MD, Assistant Professor, Department of Obstetrics, Gynecology and Women's Health, University of Medicine and Dentistry of New Jersey
Coauthor(s): Natalie E Roche, MD, Department of Obstetrics, Gynecology and Women's Health, Assistant Professor, University of Medicine and Dentistry of New Jersey
Contributor Information and Disclosures

Updated: Jun 2, 2006

Introduction

Therapeutic abortion is defined as the termination of pregnancy before fetal viability in order to preserve maternal health. In its broadest definition, therapeutic abortion can be performed to (1) save the life of the mother, (2) preserve the health of the mother, (3) terminate a pregnancy that would result in the birth of a child with defects incompatible with life or associated with significant morbidity, (4) terminate a nonviable pregnancy, or (5) selectively reduce a multifetal pregnancy.

The vast majority of abortions performed in the United States are elective. Pregnancy-related conditions that threaten maternal life are rare and difficult to define precisely. The decision to terminate a pregnancy for medical indications is generally a multidisciplinary decision including the obstetrician, a specialist in the disease entity in question, the patient, and the patient's family.

The methods used to terminate pregnancy vary according to gestational age, the indication for termination, and medical and surgical considerations relevant to the mother. Abortion can be accomplished by surgical or medical means.

Most of this article is devoted to the discussion of indications for therapeutic abortion and medical methods for termination of pregnancy. An in-depth discussion of surgical abortion is covered in Surgical Management of Abortion.

History of the Procedure

Termination of pregnancy has been practiced since ancient times and by all cultures. The indications and social context for termination of pregnancy vary with culture and time.

The use of abortion to preserve the life of the mother has been widely accepted. Early Jewish scholars' interpretation of the Talmud required that the fetus be destroyed if it posed a threat to the mother during delivery. The ancient Greeks allowed abortion under certain circumstances. Ancient Romans did not consider a fetus a person until after birth, and abortion was practiced widely. Early Christians had varying practices regarding abortion. By 1869, the Catholic church declared abortion a sin punishable by excommunication.

In the United States, legislation regarding abortion has varied with the times. Before 1800, no statutes addressed the subject of abortion. The first antiabortion legislation appeared in the 1820s; the preservation of pregnant women's health was the motivating force. During this time, the mortality rate from abortion was high, while the mortality rate from childbirth was less than 3%. By 1900, abortion in the United States at any time during pregnancy was a crime, with the exception of therapeutic abortion performed to save the mother's life.

During the 1950s, the practice of medicine came under increasing scrutiny, and guidelines were set to define the indications for therapeutic abortion. The guidelines allowed therapeutic abortion if (1) pregnancy would "gravely impair the physical and mental health of the mother," (2) the child born was likely to have "grave physical and mental defects," or (3) the pregnancy was the result of rape or incest.²⁰ In the United States, the legalization of abortion by Roe v Wade in 1973 upheld the fundamental right of a woman to determine whether to continue her pregnancy.

Problem

US statistics indicate that the vast majority of abortions are elective. Therapeutic abortion is rare. The ability to define therapeutic abortion performed for maternal indications is difficult because of the subjective nature of decisions made about potential morbidity and mortality in pregnant women. A variety of medical conditions in pregnant women have the potential to affect health and cause complications that may be life threatening.

Prenatal screening in the form of prenatal diagnostic testing continues to improve the antepartum diagnosis of fetal anomalies. The decision to continue or terminate a pregnancy complicated by fetal anomalies is a difficult decision. The most difficult decisions are associated with anomalies that are unpredictable or highly variable in their expression.

The increase in the use of assisted reproductive technologies has been associated with an enormous increase in multifetal pregnancies. Twins have increased in frequency from 1 set per 90 pregnancies to 1 set per 45 pregnancies. Higher-order multifetal pregnancies have quadrupled in the past 20 years. These pregnancies are complicated by increased fetal morbidity and mortality rates, which are largely caused by prematurity and growth retardation. Selective reduction has been introduced as a technology to improve perinatal outcomes in these pregnancies and has been successful in reducing preterm deliveries and associated perinatal morbidity and mortality.

Frequency

Approximately 3-5% of all newborns have a recognizable birth defect. According to Cunningham and MacDonald¹⁰ , the suggested causes of fetal anomalies are as follows:

• Genetic (ie, chromosomal) (20-25%)
• Fetal infections (3-5%)
• Maternal disease (4%)
• Drugs/medications (<1%)
• Unknown (65-70%)

Medical complications during pregnancy encompass a wide array of medical problems, to include the following:

• Hypertensive disorders
• Diabetes mellitus
• Hematologic disorders
• Cardiovascular diseases
• Thromboembolic disorders
• Thyroid and parathyroid diseases
• Pituitary disorders
• Adrenal disorders
• Renal diseases
• Hepatic diseases
• GI tract disorders
• Pulmonary diseases
• Infectious diseases
• Neurologic diseases
• Psychiatric disorders
• Malignancies

The diseases tend to occur in frequencies compatible with those of nonpregnant age-matched women. Providing an in-depth review of this wide array of medical problems is beyond the scope of this article.

The total incidence of malignancy during pregnancy is estimated at 1 case per 1000 pregnancies. The most common cancers found in pregnant women mirror those found in their nonpregnant counterparts, to include the following:

• Cervical cancer (1 case per 2200 pregnancies)
• Breast cancer (1 case per 3000 pregnancies)
• Melanoma (0.14-2.8 cases per 1000 pregnancies)
• Ovarian cancer
• Thyroid cancer
• Leukemia (rare)
• Lymphoma
• Colorectal carcinoma (0.10-1.0 cases per 1000 pregnancies)

Presentation

Patients in need of therapeutic termination of pregnancy can be identified at any gestational age; however, the consideration of therapeutic abortion is generally limited to pregnancies at 24 weeks' gestation or less. Many patients are in the second trimester of pregnancy because of the timing of fetal assessment tools (eg, triple screen, amniocentesis, ultrasound).

Indications

The indications for therapeutic abortion, in its broadest definition, are as follows:

• To save the life of the pregnant woman
• To preserve the health of the pregnant woman
• To terminate a pregnancy that would result in the birth of a child with defects incompatible with life or associated with significant morbidity
• To terminate a nonviable pregnancy
• To selectively reduce a multifetal pregnancy

Therapeutic abortions to save the life of the mother or to preserve the health of the mother are rare events. The decision should be based on the collaborative agreement of a multidisciplinary team. At minimum, the team should consist of the patient, the obstetrician, a specialist with knowledge of the disease in question, an expert in genetic counseling, and a neonatologist. Additional members may include spiritual counselors, nurses, psychologists/psychiatrists, intensive care specialists, ethicists, and family members.

The decision to terminate the pregnancy includes consideration of the effect of the pregnancy on disease outcome, the effect of treatment on fetal outcome, the gestational age of the pregnancy, the level of attachment of the patient to the pregnancy, the desires of the patient and the father, and the availability of family resources/support. This complex situation requires thought and excellent communication among the involved parties regarding the short- and long-term consequences of the decision to abort or continue the pregnancy. The decision must be individualized for each patient. There must be an inherent acceptance of the subjective nature of decisions made in this area. The clinical situations may be rare, and clinical data available may be anecdotal, incomplete, and/or inconclusive.

Commonly accepted medical indications for therapeutic termination of pregnancy include severe hypertensive vascular disease, cardiac disease with cardiac decompensation, and certain malignancies.

Malignancy

Cervical cancer is the most common malignancy affecting pregnant women. Invasive cervical cancer is treated with surgery or radiation; both treatment modalities result in fetal death for the previable fetus. Delay of therapy is the only option that allows fetal salvage in this setting. Treatment delays to allow fetal maturation have been successfully attempted in stages IA and IB. Treatment delays for advanced disease (stages IIB-IV) are controversial. All decisions regarding delay must be individualized and must consider other factors that affect the prognosis (eg, HIV status).

The prognosis for patients with breast cancer is not adversely affected by continuation of pregnancy. The decision to terminate a pregnancy complicated by breast cancer in the first and second trimesters is determined by the degree to which the pregnancy impairs effective treatment and whether treatment presents a risk to the fetus.

The prognosis for patients with melanoma is not improved by therapeutic abortion. Metastatic spread of melanoma to the placenta and fetus has been reported but is very rare. This type of spread has also been reported with lymphoma, leukemia, breast cancer, lung cancer, and stomach cancer and should be addressed when counseling at-risk patients.

Fetal conditions

A pregnancy in which the fetus has defects that are either incompatible with life or associated with significant morbidity can be an indication for therapeutic abortion. The number of fetal conditions that can be identified during pregnancy is always expanding because of improvements in technology available for antenatal diagnosis. The following fetal conditions are identifiable:

• Chromosomal disorders
• X-linked disorders
• Metabolic disorders
• Neural tube defects
• Structural anomalies associated with exposure to teratogens
• Structural anomalies of multifactorial or unknown etiology

Multifetal pregnancies

Multifetal pregnancies are associated with high fetal morbidity and mortality rates. In this setting, morbidity and mortality are associated with high rates of preterm delivery and growth retardation. Preterm birth rates at less than 33 weeks' gestation are 8 times higher for twins and 24 times higher for triplets compared with singleton pregnancies. Each additional fetus in a pregnancy reduces the length of the pregnancy by approximately 3.6 weeks. After birth, the mortality rates for infants born in multiple pregnancies remain elevated from birth to age 5 years, even after controlling for growth restriction.

Multifetal reduction has been shown to reduce the risk of preterm delivery for the remaining fetuses. However, the incidence of prematurity in reduced pregnancies appears to remain higher than in spontaneous pregnancies of the same fetal number. An overall reduction in morbidity-improved survival rates occurs in reduced pregnancies compared with pregnancies in which reduction is not performed.

Relevant Anatomy

Adequate evaluation of uterine size is mandatory. Physical examination may be inadequate for uterine sizing because of the following factors:

• Obesity
• Patient apprehension with voluntary guarding
• Presence of a retroverted uterus
• Firm abdominal musculature
• Uterine leiomyoma

Obtaining ultrasound confirmation of gestational age is common practice when a therapeutic abortion is planned. Anticipating potential complications associated with the abortion procedure is important.

Consider anatomic problems that may contribute to technical difficulties during an abortion. Make every attempt to minimize complications because of their impact on a patient who may already be compromised because of an underlying disease. A small, stenotic, or scarred cervical os may impair the cervical dilation necessary for safe surgical terminations of pregnancy. A long vaginal canal may also make the use of surgical instruments difficult, and labor induction may need to be considered.

The presence of uterine leiomyomas may make uterine sizing erroneous and the dilation of the cervix difficult or impossible and may contribute to increased blood loss at the time of either surgical or medical abortion procedures.

Abnormal placentation (ie, placenta previa, placenta accreta, placenta percreta) is associated with high parity and previous uterine surgery. This issue must be addressed carefully. Abnormal placentation requires surgical intervention with careful consideration of the anticipated amount of blood loss. The selected surgical abortion method should cause minimal blood loss and be of limited invasiveness. For certain patients, special interventions, such as embolization using interventional radiology techniques, may be needed on a standby basis.

The presence of uterine anomalies (eg, uterus didelphys, unicornuate uterus, septate uterus) may make entering and emptying of the uterus complicated. If surgical abortion is selected, ultrasound guidance during the procedure may be helpful. The abortion of a multiple gestation may make surgical abortions more challenging, and the use of ultrasound guidance is helpful. Data are not available for the use of medical abortion in this setting.

Careful consideration of the choice of anesthesia must be based on the medical, psychiatric, and emotional condition of the patient. Consultation with anesthetists, medical specialists, and psychiatric specialists may be necessary to determine the best choice of anesthesia for an individual patient. In general, local anesthesia affords the greatest safety. General anesthesia for surgical abortions is associated with greater overall risk of anesthesia complications and hemorrhage.

Contraindications

Absolute contraindications to termination of pregnancy are virtually unknown. In the face of significant maternal risk of medical or psychiatric morbidity/mortality, continuation of pregnancy usually presents far greater risk than termination of pregnancy. A particular type of abortion procedure or the timing of abortion may be contraindicated based on the current medical, surgical, or psychiatric condition of a patient. For example, medical abortion is contraindicated in patients with the following conditions:

• Clotting disorders
• Severe liver diseases
• Renal diseases
• Severe cardiac diseases
• Long-term steroid use
• Medical conditions or use of medications that preclude the use of medical abortion medications
• Adrenal failure
• Undiagnosed adnexal masses
• Ectopic pregnancy (except with use of methotrexate)

Medical abortion should be performed with caution in patients with the following conditions:

• Severe anemia
• Poorly controlled bowel disease (may cause an exacerbation of symptoms)

Surgical abortion is contraindicated in patients with the following conditions:

• Hemodynamic instability
• Profound anemia
• Profound thrombocytopenia

Instillation abortion techniques are contraindicated in patients with the following conditions:

• Active pelvic infections
• Inability to tolerate a solute load (saline only)
• Asthma, glaucoma, epilepsy, hypertensive cardiovascular disease, pulmonary hypertension (prostaglandin F_{2 a} [PGF2 a])
• Fetal demise (saline, urea)

The rare patient with placenta accreta or placenta percreta may require consideration of laparotomy with hysterotomy/hysterectomy despite the increased morbidity and mortality risks associated with these procedures.

Multifetal reduction of pregnancy has inherent risks of rupture of membranes, preterm labor, preterm delivery, and infection, which must be balanced against the benefits of the procedure. Special circumstances, such as the selection of the presenting fetus for reduction, may present a greater risk of loss of the entire pregnancy and must be considered in the risk-benefit analysis.

In patients with significant medical or surgical risk, the choice of abortion procedure must be individualized. All abortion methods may present relative or absolute contraindications for some patients. In the face of limited or absent data for a specific clinical situation, the choice of abortion method is based on the best collective medical judgment of the team of clinicians caring for the patient.

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