The first trimester is a period of intense growth for the unborn
baby as major body systems, including neurological, circulatory,
and skeletal, are developing. Because these important systems
are forming in the first trimester, unborn babies are most
susceptible to harm during this time. You can protect your
unborn baby by avoiding substances such as alcohol, drugs,
certain medications, and illnesses such as rubella (German
measles). These harmful substances are called teratogens, which
are agents that can cause a birth defect. A teratogen is usually
something in the environment that the mother may be exposed to
during her pregnancy. The following information discusses ways
to avoid some of the most common and most harmful teratogens: -
Alcohol use. Alcohol consumption by a mother is a leading cause
of preventable birth defects, as everything a mother drinks also
goes to her unborn baby. Alcohol is broken down more slowly in
the immature body of the unborn baby than in an adult's body. In
addition, the risk o