Periconception window: advising the pregnancy-planning couple.

OBJECTIVE: To discuss the importance of the periconceptional window with regard to being a critical window of exposure. To review the empirical data related to healthy periconceptional behaviors.
DESIGN: Literature review. CONCLUSION(S): Human reproduction is a couple-dependent process. Recent literature has highlighted that the periconceptional time period is a critical window of exposure that can impact growth and development. In advising the pregnancy-planning couple, it is of paramount importance that couples have knowledge of the timing of the fertile window to ensure that intercourse occurs on days with the maximum probability of pregnancy. Many women adopt healthier lifestyles while trying to conceive, often quitting smoking, eating healthier or taking vitamins. However, there is a lack of empirical data from prospective studies regarding which environmental exposures or behaviors are or are not safe. Noticeably absent are data regarding the effect of male partners' exposures or behaviors on couple fecundity and fertility. As we improve our ability to pinpoint the timing of conception, we should be able to better advise couples planning pregnancy.