In its technical guidelines on safe abortion, the World Health Organization (WHO) states:

Vacuum aspiration and medical abortion are preferred methods for abortion in the first trimester. Both these methods are safe, effective, and suitable for the primary level of care and should also be available at levels of care with greater capacity and in many private clinical settings.

Three methods can be used to safely and effectively terminate pregnancy in the first 12 weeks (84 days) since the woman’s last menstrual period:

• Vacuum aspiration — also called suction abortion, vacuum curettage, suction curettage, menstrual regulation or minisuction — involves removal of the uterine contents by applying suction through a cannula (thin tube) that has been inserted through the cervix. According to the World Health Organization, vacuum aspiration can be used up to 12-15 weeks since the woman’s last menstrual period, depending on the instruments available and the health-care provider’s level of training and skills.
• Medical abortion — also called medication abortion — occurs when pharmacologic agents are administered vaginally or orally to cause expulsion of the uterine contents.
• Sharp curettage — also known as dilatation and curettage (D&C) — involves emptying the uterus by scraping it with curettes (metal instruments). Mechanical dilators are used to open the cervix, and metal curettes are used to scrape the uterine walls. Heavy sedation or general anesthesia is generally required. Because of the elevated risk of complications, the WHO advises that this method should be used only when vacuum aspiration and medication abortion are unavailable (WHO, 2003).

Several methods are used to induce abortion after 12 weeks (84 days) since the woman’s last menstrual period. The two most widely used methods are dilatation and evacuation (D&E) and medication abortion. The World Health Organization lists both methods as appropriate for terminating pregnancies greater than 12 weeks’ duration.

• Dilatation and evacuation (D&E) is a procedure in which the cervix is dilated and  the uterine contents are removed using electric vacuum aspiration. D&E abortion is very safe and effective when performed by trained, experienced providers. D&E is an appropriate technique for the second trimester. It is often used in abortions for pregnancies longer than 12 weeks since the woman’s last menstrual period.
  
• Medical abortion (also called medication abortion) of pregnancies longer than 12 weeks’ duration involves the use of one or more medications to cause uterine contractions that expel the pregnancy, similar to the process of a late miscarriage (spontaneous abortion). Appropriate regimens depend on the duration of the pregnancy and the types of drugs used. Medical-abortion protocols used in early abortion are not appropriate for use after 12 weeks since the women’s last menstrual period. One or more of these drugs is typically used for medication abortion after the first 12 weeks: misoprostol, mifepristone, gemeprost. Medications to induce abortion after 12 weeks are most commonly administered orally or vaginally, although other administration routes are possible. Multiple doses are generally required.