70 days' gestation as it before 63 days. There is little difference in terms of safety and efficacy between medical abortion using a combined regimen of mifepristone and misoprostol and surgical abortion (vacuum aspiration) in early first trimester abortions up to 10 weeks gestation. Medical abortion using the prostaglandin analog misoprostol alone is less effective and more painful than medical abortion using a combined regimen of mifepristone and misoprostol or surgical abortion. Vacuum aspiration in the first trimester is the safest method of surgical abortion, and can be performed in a primary care office, abortion clinic, or hospital. Complications, which are rare, can include uterine perforation, pelvic infection, and retained products of conception requiring a second procedure to evacuate. Infections account for one-third of abortion-related deaths in the United States. The rate of complications of vacuum aspiration abortion in the first trimester is similar regardless of whether the procedure is performed in a hospital, surgical center, or office. Preventive antibiotics (such as doxycycline or metronidazole) are typically given before abortion procedures, as they are believed to substantially reduce the risk of postoperative uterine infection; however, antibiotics are not routinely given with abortion pills. The rate of failed procedures does not appear to vary significantly depending on whether the abortion is performed by a doctor or a mid-level practitioner. Complications after second trimester abortion are similar to those after first trimester abortion, and depend somewhat on the method chosen. The risk of death from abortion approaches roughly half the risk of death from childbirth the farther along a woman is in pregnancy; from one in a million before 9 weeks gestation to nearly one in ten thousand at 21 weeks or more (as measured from the last menstrual period). It appears that having had a prior surgical uterine evacuation (whether because of induced abortion or treatment of miscarriage) correlates with a small increase in the risk of preterm birth in future pregnancies. The studies supporting this did not control for factors not related to abortion or miscarriage, and hence the causes of this correlation have not been determined, although multiple possibilities have been suggested. Some purported risks of abortion are promoted primarily by anti-abortion groups, but lack scientific support. For example, the question of a link between induced abortion and breast cancer has been investigated extensively. Major medical and scientific bodies (including the WHO, National Cancer Institute, American Cancer Society, Royal