Embryonic development and pregnancy test sensitivity: the importance of earlier pregnancy detection.

Embryogenesis research provides information on a time of heightened vulnerability in embryo development: the time from conception to the day a woman misses her menstrual period. During this period, it is vital for the woman to be aware of exposures, behaviors and nutritional factors that could negatively impact the developing embryo. This article discusses this critical, often-overlooked window of development and will review the various types of teratogens that affect pregnancy. Over-the-counter pregnancy tests are widely used to determine pregnancy status. Earlier test models detected only the pregnancy hormone human chorionic gonadotropin in the urine, but it is now known that there are other key forms of human chorionic gonadotropin that are relevant when determining pregnancy status. This article will explain why early knowledge of pregnancy status is important for both woman and embryo, and the role that patient education and pregnancy test choice can have on normal embryonic development.