The goal in this study is to clarify the impact of the environment on prenatal development and point out the importance of topic itself, which is often talked about too little in society, although the period from conception to birth is marked by as many changes like no other period in life. Various theorists and the two extremes were considered, but none of them can refute what the various studies conducted in the last century have resulted in - psychological and social conditions make up a large part of the development before and after birth. Therefore, pregnant woman herself can influence the prenatal development with her (ir)responsible behavior and make positive or negative changes in development. The research was conducted in the form of a semi- structured interview based on the case of, from today's perspective, young mother, but once a minor pregnant woman who became a mother when she was 15 years old and from her, subjective point of view, find out how much the environment affected on her during pregnancy and prenatal child development given the data to date. Consequently, prenatal development will be discussed so as the stages of pregnancy from conception, fetal and zygote, to the last trimester will be considered and described in more detail, and the causes and consequences of adolescent pregnancy for the mother and her child. In conclusion, the environment affects prenatal development in a big way, and during the first nine months various factors that affect postnatal life are defined, so it is necessary to provide the child and pregnant women with a healthy environment for his prenatal development.