ABORTION

INTRODUCTION

Abortion is the termination of pregnancy prior to viability of the fetus. Viability is the ability of the fetus to live independently from the mother and is defined as 24 weeks of gestation. Induced abortion can be elective (performed for nonmedical indications) or therapeutic (performed for medical indications). Abortion can be performed by surgical or medical means. This chapter will confine itself to a discussion of surgical methods of abortion.

History of the Procedure: All cultures have practiced abortion, and the practice of abortion has been documented as early as ancient times. Abortion is controversial and has been subject to an ongoing debate focused on 3 central questions: 1) When should abortion be allowed? 2) Who should make the decision about abortion, the individual or society? 3) When does the fetus become human?

The answers to the 3 central questions have varied with time, place, and culture. In the US, the modern debate about abortion began in the 1820s with antiabortion legislation targeted against high maternal mortality rates associated with abortion. Notable in the 20th century was Roe v Wade, the 1973 Supreme Court ruling that guaranteed the fundamental right of a woman to decide whether or not to terminate her pregnancy. The 1973 Supreme Court ruling did not end the controversy surrounding abortion, and it continues today with legislation and legal intervention at the state and federal levels.

Problem: Abortion is one of the most common surgical procedures performed for American women. Based on estimated lifetime risk, each American woman is expected to have 3.2 pregnancies, of which 2 will be a live birth, 0.7 will be an induced abortion, and 0.5 will be a miscarriage. Using 1996 data, this translates into 3.89 million live births, 1.37 million abortions, and 0.98 million miscarriages.

The abortion rate in the US has declined steadily from a peak of 29.4 per 1000 women aged 15-44 years to a low of 22.9 per 1000 women in 1996.

Frequency: Most abortions in the US were performed in the first trimester?8% of abortions were at less than 13 weeks of gestation, 55% of abortions were at less than 8 weeks of gestation, and 18% of abortions were at less than 6 weeks of gestation.

The trend over the last reported years (1992-1997) has been toward abortions performed earlier in gestation.

For the abortions reported in the US, 97% are performed using surgical methods.

Etiology: Abortion is by definition a failure. The failure can be the result of the mother’s lack of access to care, contraceptive method failure, contraceptive use failure, or failure of the normal reproductive process (fetal anomalies, fetal death, maternal illness).

Data from 1987 documented that 50% of all pregnancies in the US were unintended. The large number of unintended pregnancies accounts for the bulk of the terminations of pregnancy in the US.

Clinical: The decision to end a pregnancy may be made prior to the diagnosis of pregnancy. Many women present for pregnancy diagnosis with a simultaneous request for abortion. Women should be encouraged to have early diagnosis of pregnancy for the following reasons:

¡P The earlier the diagnosis of pregnancy, the greater the number of abortion methods available.

¡P Earlier diagnosis of pregnancy allows a greater chance for early abortion and lower complication rates.

¡P Earlier diagnosis of pregnancy allows earlier diagnosis of possible ectopic pregnancy and lower complication rates.

¡P Earlier diagnosis of pregnancy enables earlier entry into prenatal care and earlier diagnosis of indications for therapeutic abortion.

Obtain medical, surgical, and obstetric/gynecological history to help differentiate healthy from abnormal pregnancies. Symptoms of normal pregnancy include anorexia, nausea, vomiting, breast tenderness, amenorrhea, and lethargy. Symptoms of abnormal pregnancy include abdominal pain, vaginal bleeding, passage of tissue, and near syncope or syncope.

Most elective abortions are performed in women aged 20-24 years. Most therapeutic abortions are performed in women older than 35 years. The most likely profile of patient requesting an elective abortion is that of a white, unmarried woman who is younger than 25 years. Females younger than 15 years represent less than 1% of all abortion patients. The number of unintended pregnancies has decreased, with a subsequent decrease in elective abortions. This decrease has been attributed in part to increasing condom and long-acting hormonal contraceptive use in young women and a shift in demographics to an older, less fertile female population.

Many patients who present with an abortion request are upset and frightened. Adequate counseling with discussion of all options available for the pregnancy and explanation of abortion options, risks, and complications is mandatory.

INDICATIONS

Elective abortion involves nonmedical indications for termination of pregnancy as determined by the patient.

Therapeutic abortion is termination of pregnancy for a medical indication, including the following:

¡P Medical illness in the mother in which continuation of the pregnancy has the potential to threaten the life or health of the mother: Consider the present medical condition and a reasonable prediction of future circumstances because few medical indications are absolute.

¡P Rape or incest

¡P Fetal anomalies when pregnancy outcome is likely to be birth of a child with significant mental or physical defects

¡P Fetal death

RELEVANT ANATOMY AND CONTRAINDICATIONS

Relevant Anatomy: Adequate evaluation of uterine size is mandatory. Physical exam may be inadequate for uterine sizing. Common causes of inadequate sizing by physical exam are obesity, uterine fibroids, patient apprehension with voluntary guarding, retroverted uterus, and firm abdominal musculature in young patients.

¡P Obtaining ultrasound (US) confirmation of gestational age prior to abortion in the second trimester is common practice.

¡P Small or stenotic cervical os may prevent adequate dilatation for a surgical abortion.

¡P Uterine leiomyoma may make uterine sizing by physical exam erroneous, may make dilatation of the cervix difficult or impossible, and may make introduction of suction tips and curets into the uterine cavity difficult or impossible. US prior to abortion is recommended. US guidance during abortion procedure may be helpful.

¡P Previous uterine surgery may increase the risk of perforation during surgical abortion.

¡P Previous uterine surgery and high parity are associated with greater likelihood of placenta praevia, placenta accreta, and placenta percreta. Recommend surgical abortion in a setting where blood transfusion and access to laparotomy are available.

¡P Scarring of the cervix caused by cone biopsy or delivery may increase risk of cervical stenosis and damage to cervix at dilatation. Consider passive dilatation with osmotic dilators (laminaria, Dilapan).

¡P Uterine anomalies (uterine septum, double uterus) may make entry into and emptying of the uterus complicated. Recommend US guidance during abortion procedure.

¡P Multiple gestations may make surgical abortion more technically challenging. Recommend adequate cervical dilatation and equipment appropriate to uterine size, not dates.

¡P For an adnexal mass, the physician must obtain a US to rule out ectopic pregnancy and determine the nature of the mass.

¡P Selection of surgical abortion procedure depends primarily on gestational age of the pregnancy.

¡P Careful consideration of choice of anesthesia must be based on the medical, psychiatric, and emotional condition of the patient. Local anesthesia affords greatest safety. General anesthesia is associated with greater risk of anesthesia complications and hemorrhage.

Contraindications: Absolute contraindications are virtually unknown. If abortion presents a medical risk to the patient, then continuation of the pregnancy presents an even greater risk. The type and timing of an abortion procedure or method may be contraindicated based on the medical, surgical, or psychiatric condition of the patient.

¡P Medical abortion is contraindicated in patients with clotting disorders, severe liver disease, renal disease, cardiac disease, and chronic steroid use.

¡P Surgical abortion is contraindicated in hemodynamically unstable patients, profound anemia, and profound thrombocytopenia.

¡P The rare instance of placenta accreta and percreta in the second trimester may necessitate laparotomy with hysterotomy or hysterectomy.

WORKUP

Lab Studies:

• A pregnancy test, determination of blood type, and CBC are the minimum lab studies required for abortion.

• A pregnancy test is required because non–pregnancy-related causes of amenorrhea exist.

• Determining blood type is required so that women who are Rh negative can be identified and treated with RhoGAM to prevent sensitization of subsequent pregnancies.

• CBC is recommended to identify patients with significant anemia. These patients are at increased risk for clinically significant blood loss that may necessitate transfusion (particularly in procedures performed in second trimester pregnancies). The patients are managed best in a setting where transfusion is available.

• Screen for common sexually transmitted diseases (eg, Chlamydia, Gonorrhea, rapid plasma reagin (RPR), HIV, hepatitis B) in geographic areas with high prevalence (eg, urban, inner city) and in age groups commonly at risk (women <25 y).

• Additional testing will be dictated by findings on history and physical exam.

• Coagulation studies are indicated in patients with a history of bruising, abnormal bleeding, hemorrhage with previous surgical procedures, or petechiae on physical exam.

• Liver function tests are indicated in patients with ethyl alcohol (ETOH) abuse, hepatitis, hepatomegaly, or jaundice.

• Renal function tests are indicated in patients with history of renal disease or dialysis.

Imaging Studies:

• Pelvic US is indicated prior to surgical abortion under the following circumstances:

• Dates of conception are uncertain.

• Uterine sizing by physical exam is inadequate.

• A discrepancy between the uterine size and date of conception exists.

• The pregnancy is in the second trimester.

• Uterine leiomyoma are present.

• Uterine anomalies are known or suspected.

• Adnexal or pelvic masses are known or suspected.

• Patient has vaginal bleeding.

• Patient has pelvic pain.

• Patient has had a previous ectopic pregnancy.

• Chest x-ray may be indicated by findings on history and physical exam.

Other Tests:

• ECG may be indicated based on age, findings on history or physical exam, and type of anesthesia requested.

Histologic Findings: Requirements for pathological exam of products of conception (POC) after surgical abortion are determined by state regulations. Many states require exam of fetal tissue after abortion. Request pathological exam of tissue in the following circumstances, even if no state requirement exists:

¡P Tissue obtained is less than expected based on gestational age.

¡P Scant tissue is obtained.

¡P Tissue is abnormal in appearance (eg, grapelike appearance consistent with molar pregnancy).

¡P Ectopic pregnancy is suspected.

¡P Sac, placenta, and/or fetal tissue are not identifiable on gross exam in a first trimester abortion.

¡P Placenta and/or fetal tissue are not identifiable on gross exam in a second trimester abortion.

¡P Tissue not consistent with POC is identified in the specimen (eg, fat).

TREATMENT

Medical therapy: Surgical abortion may be used as a backup for failed medical abortions. For a discussion of medical abortion, see Therapeutic Abortion.

Several modalities can be used to prepare the cervix for dilation at the time of surgical abortion, including oral and vaginal prostaglandin analogues.

Surgical therapy: The methods available for surgical abortion include the following:

¡P Manual vacuum aspiration (menstrual extraction) is used at 4-10 weeks of gestation (99.2% effective).

¡P Suction curettage is used at 6-12 weeks of gestation.

¡P Curettage is used at 4-12 weeks of gestation but is not used currently because of increased blood loss and retained POC compared to suction.

¡P Dilation and extraction (D&E) is used at 13-24 weeks of gestation.

¡P Hysterotomy is used at 12-24 weeks of gestation and is reserved for rare instances when all other methods of abortion fail or are contraindicated.

¡P Hysterectomy is reserved for rare instances when other gynecological pathology dictates removal of the uterus.

Abortions performed earlier in gestation have lower risk of morbidity and mortality. In the US, 88% of abortions are performed at less than or equal to 13 weeks of gestation. Ninety seven percent of abortions are performed using surgical methods.

In the second trimester, options for abortion include D&E, labor induction methods, and hysterotomy/hysterectomy. D&E is the safest form of abortion in the second trimester, followed with increasing morbidity/mortality by labor induction methods and, finally, hysterectomy/hysterotomy, which holds the highest risk.

Preoperative details: Provide detailed counseling about procedure, risks, complication rates, and alternatives. For manual vacuum aspiration, suction curettage, and D&E, obtain patient’s medical history with an emphasis on bleeding disorders and allergies. Obtain the patient’s obstetric/gynecological history with an emphasis on last menstrual period (LMP), fibroids, and uterine anomalies. Perform a pelvic exam to determine uterine size and position and rule out pelvic mass. Lab work is required, including—aterminimum—ppregnancy test and Rh status. Vaginal probe US can be used as indicated for preoperative confirmation of pregnancy, gestational age, and location of pregnancy, and it can be used postoperatively to confirm removal of the pregnancy.

Assess the patient's need for pain relief and administer pain medication (ibuprofen 600-800 mg or equivalent medication usually is sufficient). Administering misoprostol (0.4 mg PO or 0.8 mg intravaginally) is optional prior to procedure to dilate cervix. For suction curettage, administering 2.5-5 mg of Valium to an unusually agitated patient on arrival is optional.

For suction curettage make sure the patient has nothing by mouth (NPO) after midnight the day prior to abortion if the patient elects to have general anesthesia. Perform pelvic US as indicated. Passive dilation with laminaria, Dilapan, or misoprostol is optional.

For D&E, pelvic US is routine. Passive dilation with laminaria or Dilapan is routine. Double placement of laminaria or Dilapan separated by a minimum of 6 hours is routine for gestations of longer than 20 weeks. Termination of fetal life with intracardiac KCl prior to D&E for gestations of longer than 20 weeks is optional.

For hysterotomy/hysterectomy, perform preoperative care as for all major surgery. Hysterotomy/hysterectomy will require regional or general anesthesia. Pelvic US is mandatory. Consider second opinion prior to procedure. The procedure requires intensive counseling because of increased morbidity and mortality associated with procedure and because of fertility issues.

Intraoperative details: For manual vacuum aspiration, suction curettage, and D&E, place the speculum in the vagina and prepare the vagina with Betadine or an alternative.

For manual vacuum aspiration, placing a paracervical block using Nesacaine 1% or lidocaine 0.5% or 1% is optional. Grasp the anterior lip of the cervix with the tenaculum. Pass the appropriately sized suction tip into the uterus or gently dilate the cervix with suction tips of increasing size or metal dilators. After the suction tip is placed in the uterus, prepare the syringe by creating a vacuum and attach the tip to the syringe. Blood, POC, and bubbles will enter the syringe. Gently rotate the suction tip while gradually withdrawing the syringe to the internal os (do not remove the suction tip beyond the cervix). The procedure is complete when a gritty sensation is appreciated, when the uterine walls adhere to the suction tip (drag is felt), when foam appears in the tip/syringe, and when no more tissue is evacuated from the uterus. Examine POC.

For suction curettage, paracervical block is routine. After the suction tip is placed in the uterus (see above), attach it to the suction tubing and activate suction. Gently rotate the suction tip from the fundus to the cervix until POC has been removed. Use of a metal curette after suction curettage is routine. Soft suction tips are less likely to damage the uterus than rigid tips, but they have the disadvantage of a greater tendency to clog. Soft tips are less likely to permit entry into the uterus in the case of extreme flexion of the uterus and myomas. In the case of extreme flexion of the uterus, place the tenaculum on the posterior lip of cervix; this may allow entry into the uterus. Use of polyp forceps for removal of the placenta is optional. POC can be identified in the suction tubing during the procedure. Completion of the procedure is identified when the uterus decreases in size, no more tissue is obtained, pink-red foam appears at the os or tubing, and a gritty sensation is felt with the suctiontip or curette. Use of intravenous Pitocin is an option. Examine POC to identify fetus, placenta, and/or sac.

For D&E, assess the patient's need for anesthesia. Place the speculum in the vagina. Remove passive dilators and assess for adequate dilatation. Use of metal dilators to obtain adequate dilation is an option. Adequate dilation is the key to safety and ease of the procedure. Grasp the anterior lip of the cervix with the tenaculum. Paracervical block with local anesthetic plus vasopressin at 5 units per 15 mL of local anesthesia is an option to reduce blood loss. Rupture membranes and aspirate amniotic fluid with suction. Use forceps (Bierer or Sopher) to remove the fetus. Remove the placenta with forceps and/or suction. Sharp curettage is performed with a curette. Use of IV Pitocin is standard. Completion of procedure is identified when all of the fetus is identified on gross exam, the placenta is identified, the uterus decreases in size, vaginal bleeding is minimal, and no additional tissue is obtained on curettage.

For hysterotomy, obtain anesthesia. The patient is prepped and draped in the usual fashion for abdominal surgery. A skin incision is made, and the anterior abdominal wall is opened in the usual fashion. The uterus is identified, the uterine incision is made, and the uterine cavity is entered. The fetus is removed from the uterus in the sac, or the membranes are ruptured and the fetus is delivered. The placenta then is removed. Intravenous Pitocin is administered. Intravenous antibiotics are an option. The uterine incision is closed, usually in 2 layers. After adequate hemostasis is obtained, the abdominal incision is closed in the usual fashion.

For hysterectomy, the uterus can be removed by vaginal or abdominal approach, as determined by the size of the uterus and the indication for the hysterectomy. POC usually is removed intact at the time of hysterectomy.

Postoperative details: For manual vacuum aspiration, suction curettage, and D&E, administer RhoGAM as indicated. Surgical complications are rare. Observe the patient for a minimum of 20-30 minutes after the procedure. Postoperative pain, bleeding, syncope, and increase in uterine size require immediate attention. Consider the possibility of retained POC, uterine perforation, cervical laceration, hematometra, or heterotopic pregnancy. Perform postoperative evaluation of POC in all cases. Counseling regarding fertility and contraceptive management are mandatory. Counsel the patient regarding pain management (ibuprofen 400-600 mg or equivalent medication usually is sufficient). Review signs and symptoms of complications, including severe pain and increasing pain, heavy vaginal bleeding (more than menstrual flow), vaginal bleeding lasting longer than 2 weeks, fever and/or chills, and syncope or near syncope. Antibiotic prophylaxis is an option. Schedule a follow-up visit 2 weeks after the procedure.

For suction curettage, the length of postoperative observation is determined by the type of anesthesia used.

For D&E, methylergonovine (0.2 mg PO every 4 h for 6 doses) is an option.

Follow-up care: For manual vacuum aspiration, suction curettage, D&E, and hysterotomy/hysterectomy, schedule a follow-up visit in 2 weeks (1-2 weeks after hospital discharge for hysterotomy) to evaluate the patient for complications, to initiate contraception if not initiated previously, to review culture results if not reviewed previously, and to evaluate the pathology results.

COMPLICATIONS

Complications of surgical abortion vary with the technique used and the gestational age of the pregnancy. In general, the more advanced the gestational age at abortion, the higher the complication rate, and more invasive operative procedures have higher complication rates.

First trimester abortion

The complication rates are low?.071% for hospitalization and 0.846% for minor complications. Abortion complications requiring hospitalization include incomplete abortion (0.028%), sepsis (0.021%), uterine perforation (0.009%), vaginal bleeding (0.007%), inability to abort (0.003%), and combined pregnancy (0.002%). Minor abortion complications include infection (0.46%), repeat suction (0.18%), cervical stenosis (0.016%), cervical tear (0.01%), seizure (0.004%), and underestimate of dates (0.006%).

Manual vacuum aspiration has complication rates of the following: rate of infection is 0.7%, of perforation is 0.05%, of retained POC is 0.5%, and of repeat aspiration is 0.5-0.25%.

Second trimester abortion

In D&E, the skill and experience of the physician are the most important factors in maintaining a low complication rate. Complication rates are low but increase with gestational age. Abortion complications requiring hospitalization include perforation, hemorrhage, infection, retained POC, and inability to complete abortion. Overall rates of hospitalization are 0.6% at 13 weeks of gestation and 1.4% at 20-21 weeks of gestation. Coagulopathy is a rare complication, occurring in 191 out of 100,000 cases for D&E.

Avoid complications by obtaining adequate cervical dilatation through using passive dilators in abortions at 14 weeks of gestation and longer and using double placement of passive dilators at longer than 20 weeks of gestation. Have appropriate instruments available for morbidly obese patients (standard instruments may not have adequate length). Match surgeon’s skill and experience to the gestational age of the pregnancy to be terminated. Choose an inpatient setting for patients with severe medical conditions, anemia, placenta praevia or other abnormal placentation, pelvic masses or large leiomyomas, or problems with veins (no IV access). Choose to delay the operative procedure in cases involving acute infection, severe vaginitis, or uncertain dating of pregnancy.

Choose hysterotomy/hysterectomy as a last resort. It has the highest morbidity and mortality of all methods of abortion.

Damage to cervix

Risk is increased with previous surgery to cervix or laceration. Damage can be associated with forceful dilation with metal dilators and may be associated with damage to cervical vessels, with hemorrhage and parametrial hematoma formation. Repair damage using a transvaginal approach or laparoscopy/laparotomy. Prevent damage by avoiding forceful dilation. Passively dilate the cervix using passive dilators and/or prostaglandin analogues. Delay the procedure if adequate dilation is not achieved.

Hemorrhage

Hemorrhage can be caused by atony, retained products, or perforation. General anesthesia increases the risk of atony. Blood loss of greater than 300 cc in the first trimester is considered excessive. Treatment includes uterine massage, Pitocin or Methergine, removal of retained products, and repair of perforation as indicated. Prevent hemorrhage by ensuring complete evacuation of uterus, avoiding use of general anesthesia, and obtaining adequate cervical dilation.

Perforation

Perforation can occur with sound, dilators, curette, suction tip, forceps, or passive dilators. Increased risk is associated with previous surgery or laceration involving the cervix, previous uterine surgery, and grand multiparity. In the first trimester, most perforations are in the body of the uterus. Perforation can be recognized when an instrument passes endlessly, heavy or persistent vaginal bleeding occurs, signs of peritoneal irritation appear, or fat or other tissue appears in the specimen. If perforation is made with the sound or dilator, stop the procedure and observe the patient for a minimum of 1 hour. Antibiotic prophylaxis and US are options. Reschedule the procedure for another day. If perforation occurs with suction tip or curette, stop the procedure. Options include observation if the patient is stable and abortion is complete, laparoscopy if hemorrhage is suspected or abortion is incomplete, and laparotomy if the patient is unstable.

Mortality from abortion

Mortality is highest with the most invasive procedures and with increasing gestational age?.4 out of 100,000 cases at less than 8 weeks of gestation, 3 out of 100,000 cases at 13-15 weeks of gestation, and 12 out of 100,000 cases at longer than 21 weeks of gestation. Causes of death include infection, hemorrhage, pulmonary embolism, anesthesia complications, and amniotic fluid embolism. Death rates with hysterotomy/hysterectomy are 64.9 out of 100,000 cases at 13-15 weeks of gestation and 123 out of 100,000 cases at longer than 21 weeks of gestation.

OUTCOME AND PROGNOSIS

Surgical abortion is a safe and commonplace procedure in the US. Risk of complications is small. Most complications that occur are managed safely, with minimal long-term consequences. Fertility after abortion is only at risk in the rare instance in which a major complication occurs.

Late complications include cervical scarring and stenosis, Asherman syndrome (uterine synechiae), postinfection tubal damage, mandatory cesarean section after hysterotomy, and loss of fertility after hysterectomy.

Psychiatric illness after abortion occurs most commonly in patients with psychiatric illness prior to the abortion procedure. No evidence indicates that the abortion trauma syndrome exists.

FUTURE AND CONTROVERSIES

The decrease in total numbers of abortions is expected to continue. The trend toward earlier abortions is expected to continue. The total percentage of surgical abortions is expected to decrease with the Food and Drug Administration (FDA) approval of medical abortion. The total percentage of surgical abortions is expected to decrease because of lack of availability of trained providers. Nonsurgical management of incomplete, inevitable, and missed abortions is expected to rise as a result of the experience with medical abortion. Cost and complications of the management of abortion (induced and therapeutic) are expected to decrease as nonsurgical management increases. Controversy about the use of fetal tissue will increase. The moral, ethical, and legal debates about abortion will continue.

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