Psychology

1) A teratogen is a physical or chemical factor that affects the embryo, fetus or fertilized ovum adversely. It is always acknowledged that the fetus is extremely vulnerable to environmental injuries including teratogens. One example of teratogen is radiation it can seriously lead to fetal defects or death if exposed to large doses (i.e. radiation therapy in cervical cancer). Another teratogen that can harm the developing fetus is maternal infections such as genital herpes infection caused by Herpes Simplex Virus, a cytomegalovirus that causes extensive damage to the fetus, rubella that can cause fetal deafness, cataracts, mental and motor defects and cardiac problems, toxoplasmosis can cause central nervous system damage such as microcephaly, retinal deformities and hydrocephalus. A third example is live vaccine that potentially teratogenic like measles, mumps, poliomyelitis and rubella. They are contraindicated because they can transmit viral infection to the fetus from the mother. Another example of teratogen is drugs that can be detrimental to fetus especially drugs belong to category X. Classic examples are thalidomide (can cause Amelia or phocomelia), narcotics such as Demerol and heroin (can cause intrauterine growth restriction) and cocaine (can cause pre-term labor). The last example is cigarettes which can have teratogenic effect to the fetus like growth restriction and higher risk for sudden infant death syndrome (SIDS) (Sigelman Rider, 2009).

2) There are many reactions experienced by mother during childbirth. Psychologically, the mother normally experiences mild anxiety during birth but subsequently renews her action and forward movement. Abnormal psychological reactions include feelings of extreme fear, abandonment and overwhelming sadness that can be caused by inadequate support system and preparation. Physiologically, the mother normally has increased respiratory rate, fairly inactive gastrointestinal system, decreased blood flow to uterus, increased cardiac output and increased muscular activities. Abnormal physiological reaction includes rising or falling of blood pressure that may indicate intrauterine hemorrhage during labor, increasing apprehension and abnormal pulse which indicates bleeding (Horey, 2005).

3) There are interesting developments during stages of fetal development. During embryonic stage, the development of decidua, placenta, amniotic membranes and chorionic villi happen, it is a central core of connective tissues.  During zygotic stage, the development precedes cephalocaudal direction. This is when the origin of organ systems development occurs. The embryonic is a stage where organ systems such as reproductive, musculoskeletal, urinary, integumentary and immune system start to develop. During the prenatal development, the organogenesis is complete during the end of 8th week gestation. At the 12th week gestation, the development of fingers, toes and reflexes occurs. During 16th week gestation, the fetal heart sound is audible and spontaneous movement occurs during 20th week. On the 24th week hearing can be demonstrated by sudden response to sound and on 32nd week the fetus develops active moro reflex. On the 36th and 40th week, the fetus starts to deposit subcutaneous tissues and kicks actively (Sigelman Rider, 2009).

4) During the periods of research, the researcher must ensure that informed consent and was explained, signed and waive properly. All participants must be guaranteed safety, confidentiality, and anonymity in the final report and abide by the 1998 Data Protection Act that will protect the subjects. The researcher must never damage any participants job or job prospects by revealing confidential data about themselves and must sensitive data from becoming known to any others. Data must be reported in a way that protects both the researcher and participants from potential criminal or legal action. Withdrawal must also be available at any point during the research while observing professional standards throughout the research. Storing all documentation, reports and results in a secure and safe location is also important (Dudek, 2002).