Although the absolute risk of pregnancy is lower during the perimenopause due to decreased fertility and decreased coital frequency, unintended pregnancy occurs at ratios similar to those observed in young women, and pregnancies that do occur are at high risk for maternal complications and poor outcomes such as miscarriage or chromosomal abnormalities. Therefore all premenopausal women should receive counselling that includes discussion of sexual habits and contraception during routine health care encounters. The majority of US women in this age group use permanent contraception, but other methods can be safe and effective and can have non-contraceptive benefits. No contraceptive method is contraindicated based on age alone. However, estrogen-containing methods should be reserved for women without cardiovascular or thrombotic risk factors. The levonorgestrel intrauterine system (LNG-IUS, Mirena (R)) has particular benefits during perimenopause and is safe for use in nearly all women. The LNG-IUS is approved for treatment of heavy menstrual bleeding, a common concern during the perimenopause. A substantial literature supports the use of the LNG-IUS for endometrial protection during transition from contraception to hormone therapy, although this is off-label in the United States. Reliable contraception should be used until menopause is confirmed either by cessation of menses for 2 years prior to age 50, for 1 year after age 50, or by two elevated follicle-stimulating hormone (FSH) values >= 20-30 IU/I while off hormonal methods for at least 2 weeks. Sterility cannot be assumed until at least age 60 because spontaneous pregnancies have been reported in women up to age 59. (C) 2013 Elsevier Ireland Ltd. All rights reserved.