The revised Netherlands guideline 'Sexually transmitted diseases and neonatal herpes' recommends shortening of the follow-up period from 6 to 3 months for HIV-testing after a risky contact and a period of 6 months in case of post-exposure prophylaxis. The newly adopted follow-up period has a precedent in Sweden, where, based on the same scientific arguments, the follow-up period has been reduced to 3 months. There is little scientific information on which to base the optimal duration of the follow-up period. Therefore, two different periods are used in the Netherlands: 3 months for medical practice in the field of sexually transmitted diseases and 6 months for occupational exposure of health care workers and for blood products.