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Pregnancy Termination

In the United States, about 1.5 million legal abortions are performed each year; 90% of these procedures are performed

in the first trimester of pregnancy. Teenagers and women older than age 40 years have the highest abortion rates.

Before 16 weeks of gestation, legal abortion as practiced in the United States may be performed safely in an office

setting with simple instruments. Adequate preoperative and postoperative counseling is essential, and options to

The risk of death from first-trimester abortion is less than 1 per 100,000 abortions. The risk of death increases with

gestational age and by type of procedure. Dilation and evacuation (D&E) is safer than other options for..

Hysterotomy and hysterectomy, two procedures rarely indicated for abortion, are the least safe. General

anesthesia increases the risk of death from vacuum curettage abortion.

Maternal conditions for which termination of a desired pregnancy should be considered include cyanotic heart disease

with pulmonary hypertension, severe hypertension, previous myocardial infarction, and other comparable major

illnesses. Major anomalies and mid-trimester premature rupture of membranes are recognized fetal implications.

MENSTRUAL EXTRACTION

Sensitive pregnancy tests allow early diagnosis of pregnancy, and many women seek abortion services within 1-2 weeks

of the missed period. Abortion of these early pregnancies with a small-bore vacuum cannula.

FIRST-TRIMESTER VACUUM CURETTAGE

Beyond 7 menstrual weeks of gestation, larger cannulas and vacuum sources are required to evacuate a pregnancy.

This procedure, standard vacuum curettage, is the most common method of abortion in the United States.

Technique

Uterine size and position should be noted during a pelvic examination performed before the procedure. Ultrasonography

is advised if there is a discrepancy of more than 2 weeks between the uterine size and menstrual dating. If not already

performed, tests for gonorrhea and chlamydia should be obtained, and the cervix and vagina should be prepared with

A vacuum cannula with a diameter in millimeters that is one less than the estimated gestational age (eg, 9-mm size

for an estimated 10-week gestation) should be used to evacuate the cavity. After the tissue is removed, there should

be a quick check with a sharp curette, followed by a brief reintroduction of the vacuum cannula. The aspirated tissue

should be examined as described previously.

The risk of infectious morbidity is lowered when antibiotics are used prophylactically with induced abortion.

Tetracycline or its analogues, doxycycline and minocycline, are probably the best of the current agents for this purpose

because of their broad spectrum of antimicrobial effect and oral absorption. D-negative patients should receive D

(Rho[D]) immune globulin before leaving the facility.

Complications

The most common postabortal complication is a triad of pain, bleeding, and low-grade fever. Often, this complication

can be managed initially by administration of oral antibiotics and ergot preparations. However, most cases are caused

by retained gestational tissue or a clot in the uterine cavity.

Cervical Shock

Vasovagal syncope produced by stimulation of the cervical canal can be seen after paracervical block. Brief tonic-clonic

activity rarely may be observed and is often confused with seizure.

Perforation

The risk of perforation is less than 1 in every 1,000 first-trimester abortions. It increases with gestational age.

Hemorrhage

Excessive bleeding may indicate uterine atony, a low-lying implantation, a pregnancy of more advanced gestational age

than the first trimester, or perforation. Management requires rapid reassessment of gestational age by examination.

Hematometra

Lower abdominal pain of increasing intensity in the first 30 minutes after the procedure suggests either hematometra

or postabortal syndrome. If there is no fever or bleeding is brisk, and on examination the uterus is large, globular, and

tense, hematometra is the possible diagnosis. This condition could be mistaken for a broad ligament hematoma.

Ectopic Pregnancy, Incomplete Abortion, and Failed Abortion

Early detection of ectopic pregnancy, incomplete abortion, or failed abortion is possible if the physician performing the

operation carefully examines the specimen immediately after the abortion. The patient may have an ectopic pregnancy

if no chorionic villi are found. To detect an incomplete abortion that might result in continued pregnancy, the actual

gestational sac must be identified. The history and physical examination should be reviewed. Determination of the b-hCG

level and frozen section of the aspirated tissue and vaginal probe ultrasonography may be useful. If the b-hCG

level is greater than 1,500-2,000 mIU, chorionic villi are not identified on frozen section, or retained tissue is identified

by ultrasonography, immediate laparoscopy should be considered. Other patients may be followed closely with serial

b-hCG assays until the problem is resolved. With later (>13 weeks) gestations, all of the fetal parts must be identified

by the surgeon to prevent incomplete abortion. It is not sufficient to send the tissue to the pathologist.

Heavy bleeding or fever after abortion suggests retained tissue. If the postabortal uterus is larger than 12-week size,

it is wise to perform preoperative ultrasonography to determine the amount of remaining tissue. When fever is present,

high-dose intravenous antibiotic therapy should be initiated, and curettage should be performed shortly thereafter.

Because of the need to cover a broad spectrum of possible pathogens, a combination of two or three agents is

suggested. If there is hemolysis or failure of the patient to improve within 12-24 hours after uterine evacuation,

hysterectomy may be indicated and can be lifesaving.

Complications and Fragmented Care

Patients who have recently had an abortion and are experiencing complications often seek care at a local hospital

emergency department. A physician managing such a patient should make every effort to communicate with the

abortion provider to learn the details of the procedure, any suspected complications, results of screening tests, results

of the fresh examination of the aborted tissue, and whether D immune globulin was given if the patient is D negative.

MEDICAL ABORTION IN THE FIRST TRIMESTER

Mifepristone (RU 486) is an analogue of norethindrone with high affinity for progesterone receptors. It acts as a false

transmitter and blocks natural progesterone. It can effectively induce an abortion in an early gestation after a single oral

dose. The effectiveness is increased to approximately 95% by the addition of a low-dose prostaglandin analogue.

In France, where the drug has been used extensively, women with amenorrhea of less than 50 days and pregnancy

confirmed by serum b-hCG or ultrasonography receive an oral dose of mifepristone on day 1. On day 3, the patient

returns for prostaglandin (sulprostone or gemeprost) and D immune globulin if she is D negative. Patients remain in

the clinic for 4 hours, during which time expulsion of the pregnancy usually occurs. The patient then returns 8-15 days

later for measurement of b-hCG or ultrasonography. In more than 17,000 cases treated in France, complete abortion

was achieved in 95% of cases.

Failed abortion or excessive bleeding requires vacuum curettage. No serious complications or side effects have

occurred with mifepristone in this dosage. However, sulprostone, the prostaglandin E2 analogue used in Europe, has

been associated with myocardial infarction in three cases, resulting in one death. All three women were cigarette

smokers and were older than age 35. Misoprostol, the prostaglandin E1 analogue used with mifepristone in the United

States, has not been related to myocardial ischemia.

Another effective medical regimen for early abortion is the combination of the antifolate agent methotrexate with

misoprostol. Methotrexate is given as a single intramuscular dose followed 5-7 days later with vaginal misoprostol.

Efficacy appears to be slightly less than that observed with the mifepristone and misoprostol combination, and bleeding

may last longer. In the higher doses used to treat malignancy, methotrexate can have significant side effects, but these

are extremely rare with the low-dose regimen described above.

SECOND-TRIMESTER ABORTION

Most abortions are performed before 13 menstrual weeks. Later abortions are generally performed because of fetal

defects, maternal illness, or maternal age. Younger women are much more likely to request abortion after 12 weeks.

Dilation and Evacuation

Transcervical instrumental evacuation of the uterus (D&E) is the method most commonly used in the United States for

mid-trimester abortions before 21 menstrual weeks. Two D&E techniques are used and differ primarily in the preparatory

steps that precede the evacuation. In the one-stage technique, forcible dilation is performed slowly and carefully to

sufficient diameter to allow insertion of large, strong ovum forceps for evacuation. The better approach is a two-stage

procedure in which multiple laminaria are used to achieve gradual dilatation over several hours before extraction.

Overnight placement of one set of laminaria is sufficient preparation for the early mid-trimester, but beyond 18-20

weeks, two sets of laminaria and 2 days of preparation are often used. Oral tetracycline or doxycycline should be started

after laminaria insertion and continued for 2 days after uterine evacuation. Uterine evacuation is accomplished with

long, heavy forceps, using the vacuum cannula to rupture the fetal membranes, drain amniotic fluid, and ensure

complete evacuation. A large-bore, 16-mm vacuum system facilitates the procedure.

The procedure causes discomfort despite a paracervical block, and most patients will benefit from conscious sedation.

If general anesthesia is elected, potent inhalation agents should be avoided or used only in low concentrations to

avoid uterine atony and increased blood loss. Standard care of the anesthetized patient must be provided, with

continuous monitoring of tissue oxygenation and end-expiratory carbon dioxide and frequent monitoring of vital signs.

The patient must be closely supervised until she is fully recovered from anesthesia.

Preoperative ultrasonography is necessary for all cases 14 weeks and beyond. Intraoperative real-time

ultrasonography helps to locate fetal parts within the uterus. Paracervically administered vasopressin has been demonstrated

to significantly reduce bleeding, but vasopressin must be used with caution. A maximum of 4 units should be

used, and it is usually diluted with saline or Xylocaine. Vasopressin should not be used in women with heart disease

or hypertension. Intravenous oxytocin is begun early in the procedure, just after rupture of the membranes.

Fetal Death In Utero

Fetal death in utero can be managed with D&E, provided that the surgeon is familiar with the procedure. Vaginal

prostaglandin E2 is highly effective for this problem, usually producing fetal abortion in about 10 hours, but often with

significant vomiting, diarrhea, and fever as side effects. Beyond 28 weeks of gestation the full dose of vaginal

prostaglandin E2 should not be used, or overstimulation and uterine rupture may occur. The standard suppository can

be cut into quarters and administered 5 mg at a time for better control of uterine activity. The same low-dose regimen

can be used cautiously in patients with asthma if immediate respiratory support (inhalation) is available. Blood or

amniotic fluid may impair vaginal absorption of the prostaglandin. Coagulation studies should be obtained

preoperatively because disseminated intravascular coagulopathy is a significant risk after either D&E or vaginal

prostaglandin E2 for management of fetal death.

Intrauterine Prostaglandins

Intraamniotic prostaglandin is an effective abortion regimen, but it has several disadvantages, including incomplete

abortion, the need for a second injection in many cases, the risk of cervical rupture in the primigravida, and the lack

of a direct toxic effect on the fetus. Results with intraamniotic prostaglandin F2ca are much improved if overnight

Systemic Prostaglandins

Three different prostaglandins are available for systemic administration: prostaglandin E2 vaginal suppositories;

carboprost tromethamine for intramuscular injection; and misoprostol, an analogue of prostaglandin E1. Prostaglandin

E2 is given as a 20-mg vaginal suppository every 3 hours. The mean time to abortion is 13.4 hours, with 90% of patients

aborting by 24 hours. When 250 mcg of carboprost tromethamine is given intramuscularly every 2 hours, the mean time

to abortion is 15-17 hours, with about 80% of patients aborting by 24 hours. Misoprostol is given vaginally as a single

0.200-mg tablet every 12 hours. Mean time to abortion is comparable to that of the other two prostaglandin regimens.

High-Dose Oxytocin

Oxytocin in sufficient doses can be effective as a primary abortifacient in the mid-trimester. Fifty units is given in 500

mL of 5% dextrose and normal saline over a 3-hour period. After 1 hour of rest, the oxytocin infusion is repeated, using

100 units of oxytocin in the next 500-mL infusion, which is also given over 3 hours. If abortion does not occur, each

Hypertonic Saline

Historically, hypertonic saline is important because it was the first effective labor-induction method for mid-trimester

abortion. Maternal hazards unique to hypertonic saline include cardiovascular collapse, pulmonary and cerebral edema,

OTHER APPROACHES

Hysterotomy and Hysterectomy

Hysterotomy is essentially a cesarean delivery. There is little indication for this procedure as the primary method for

abortion because the risk of major complications and death is greater with hysterotomy and hysterectomy than for any

other abortion technique. In most cases, failed abortion is now managed with parenteral prostaglandins, and the only

time hysterotomy should be used for a failed abortion is when a uterine anomaly is present.

Selective Reduction

In cases of multifetal pregnancies, selective reduction by means of ultrasound-guided intracardiac injection of potassium

chloride has been practiced as a means of avoiding the risks of extreme prematurity for the surviving pregnancies.

Coagulation surveillance is advised after second-trimester procedures. Selective reduction should not be attempted with

Subsequent Reproduction

Legal abortion as currently practiced in the United States has no measurable adverse effect on later reproduction. This

probably reflects the safety of current abortion technology. Most abortions are performed by vacuum curettage under

local anesthesia in the first trimester. The impact of mid-trimester methods on subsequent pregnancy is less well