Suction aspiration, or "vacuum curettage," is the abortion technique used in most first trimester abortions. A powerful suction tube with a sharp cutting edge is inserted into the womb through the dilated cervix. The suction dismembers the body of the developing baby and tears the placenta from the wall of the uterus, sucking blood, amniotic fluid, placental tissue, and fetal parts into a collection bottle.
Great care must be taken to prevent the uterus from being punctured during this procedure, which may cause hemorrhage and necessitate further surgery. Also, infection can easily develop if any fetal or placental tissue is left behind in the uterus. This is the most frequent post-abortion complication. 
Dilatation (Dilation) and Curettage (D&C)
In this technique, the cervix is dilated or stretched to permit the insertion of a loop shaped steel knife. The body of the baby is cut into pieces and removed and the placenta is scraped off the uterine wall.  Blood loss from D & C, or "mechanical" curettage is greater than for suction aspiration, as is the likelihood of uterine perforation and infection. 
This method should not be confused with routine D&C’s done for reasons other than undesired pregnancy (to treat abnormal uterine bleeding, dysmenorrhea, etc.). 
Dilatation (Dilation) and Evacuation (D&E...also known as a Dismemberment Abortion)
Used to abort unborn children as old as 24 weeks, this method is similar to the D&C. The difference is that forceps with sharp metal jaws are used to grasp parts of the developing baby, which are then twisted and torn away. This continues until the child’s entire body is removed from the womb. Because the baby’s skull has often hardened to bone by this time, the skull must sometimes be compressed or crushed to facilitate removal. If not carefully removed, sharp edges of the bones may cause cervical laceration. Bleeding from the procedure may be profuse. 
Dr. Warren Hern, a Boulder, Colorado abortionist who has performed a number of D&E abortions, says they can be particularly troubling to a clinic staff and worries that this may have an effect on the quality of care a woman receives. Hern also finds them traumatic for doctors too, saying "there is no possibility of denial of an act of destruction by the operator. It is before one's eyes. The sensation of dismemberment flow through the forceps like an electric current." 
Second & Third Trimester
Abortionists sometimes refer to these or similar types of abortions using obscure, clinical-sounding euphemisms such as "Dilation and Extraction" (D&X), or "intact D&E" (IDE) which mask the realities of how the abortions are actually performed. 
This procedure is used to abort women who are 20 to 32 weeks pregnant -- or even later into pregnancy.* Guided by ultrasound, the abortionist reaches into the uterus, grabs the unborn baby’s leg with forceps, and pulls the baby into the birth canal, except for the head, which is deliberately kept just inside the womb. (At this point in a partial-birth abortion, the baby is alive.) Then the abortionist jams scissors into the back of the baby’s skull and spreads the tips of the scissors apart to enlarge the wound. After removing the scissors, a suction catheter is inserted into the skull and the baby’s brains are sucked out. The collapsed head is then removed from the uterus.
* Babies born at 23 weeks or more often survive.
This procedure eliminates that possibility.
Similar to the Caesarean Section, this method is generally used if chemical methods such as salt poisoning or prostaglandins fail (see pp. 12-14). Incisions are made in the abdomen and uterus and the baby, placenta, and amniotic sac are removed.  Babies are sometimes born alive during this procedure, raising questions as to how and when these infants are killed and by whom.
This method offers the highest risk to the health of the mother, because the potential for rupture during subsequent pregnancies is appreciable.  In the first two years of legal abortion in New York State, the death rate from hysterotomy was 271.2 deaths per 100,000 cases. 
There is always the possibility that a late term abortion could end up in a live birth. Already, there have been two reported cases where babies have survived the horror of partial birth abortion.
Support from the Medical Community
The American Medical Association, the nation’s largest physician’s lobby, supports a ban on partial birth abortion. In a letter to Congress, the AMA wrote, "The bill would clearly define the prohibited procedure so that it is clear on the face of the legislation what act is to be banned." The AMA letter added, "Although our general policy is to oppose legislation criminalizing medical practice or procedure, the AMA has supported such legislation where the procedure was narrowly defined and not medically indicated." HR 1122 now meets both those tests.
The Congressional bill is identical to the wording of the proposed referendum. Former US Surgeon General Dr C. Everett Koop testified in support of the Maine bill in April 1999, stating "This controversial, if not grotesque, procedure is hazardous to the mother's health and future fertility"..."It is never a necessary procedure for either mother or child". This is a narrowly focused proposal that protects the health of women and the lives of children."
In addition, over 700 specialists in maternal and fetal health have organized to refute the misinformation surrounding partial birth abortions. They have organized under the name PHACT - PHysicians' Ad-hoc Coalition for Truth. They say “Contrary to what abortion activists would have us believe, partial birth abortion is never medically indicated to protect a woman’s health or her fertility. In fact, the opposite is true: The procedure can pose a significant and immediate threat to both the pregnant woman’s health and her fertility.”
9. Phillip G. Stubblefield, "First and Second Trimester Abortion," in Gynecologic and Obstetric Surgery, ed. David H. Nichols (Baltimore: Mosby, 1993) p. 1016. Also, the U.S. Centers for Disease Control (CDC), "Abortion Surveillance: Preliminary Data -- United States, 1991, " Morbidity and Mortality Weekly Report, Vol. 43, No. 3, 1994, p. 43, puts the percentage of suction curettage abortions relative to other techniques at 98%, though the CDC admits that their numbers include a number of D & E abortions which should be classified otherwise (personal communication with Lisa Koonin,Division of Reproductive Health, CDC, March 6, 1996).
10. U.S. Senate Report of the Committee on the Judiciary, Human Life Federalism Amendment, Senate Joint Resolution 3, 98th Congress, 1st Session, legislative day June 6, 1983, p. 36. (Hereafter referred to asHuman Life Federalism Amendment).
11. A. Jefferson Penfield, M.D., Gynecologic Surgery Under Local Anesthesia, (Baltimore: Urban & Schwarzenburg, 1986), p. 79.
12. Jane E. Hodgson, M.D.,"Abortion by vacuum aspiration," Abortion and Sterilization: Medical and social aspects, Jane E. Hodgson, ed. (New York: Academic Press, Grune and Strathon, 1981), pp. 256-258.
13. Ibid, pp. 256, 260-261.
14. Human Life Federalism Amendment, cited in note 10, p. 36.
15. F. Gary Cunningham, M.D., et al, Williams Obstetrics, 19th ed. (Norwalk, CT: Appleton & Lang, 1993), p.683.
16. Penfield,cited in note 11, pp. 50-51.
50. Warren M. Hern, M.D., Abortion Practice (Philadelphia: J.B. Lipincott Company, 1984), pp. 153-154. See also Human Life Federalism Amendment, cited in note 10, p. 36.
51. Warren M. Hern, M.D., and Billie Corrigan, R.N., "What About Us? Staff Reactions to the D & E Procedure," paper presented at the Annual Meeting of the Association of Planned Parenthood Physicians, San Diego, California, October 26, 1978.
69. Some have also used the highly descriptive term "brain suction abortion" to refer to the procedure.
70. See Maureen Hack, et.al, "Very Low Birth Weight Outcomes of the National Institute of Child Health and Human Development Neonatal Network," Pediatrics, Vol. 87, No. 5 (May 1991), p58.
71 . Dr. Martin Haskell described the partial-birth abortion procedure, which he called "dilation and extraction,"at a Sept. 1992 meeting of the National Abortion Federation, a trade association of abortion providers. He said he had done 700 of these "procedures." See Martin Haskell, M.D., "Dilation and Extraction for Late Second Trimester Abortion," in "Second Trimester Abortion: From Every Angle," Fall Risk Management Seminar, September 13-14, 1992, Dallas, Texas, National Abortion Federation. See also Diane Gianelli, "Shock-tactic ads target late-term abortion procedure," American Medical News (July 5, 1993), pp. 3, 15-16.
72. Human Life Federalism Amendment, cited in note 10, p. 37.
73. Cunningham, et al, cited in note 15, p. 683.
74 . P. Diggory, "Hysterotomy and hysterectomy as abortion techniques," in Abortion and Sterilization, ed. Hodgson, cited in note 12, p. 326.
*Information provided by National Right to Life Committee website.