Question

2b)Discuss genetic influences on pregnancy

Answer 1

Genes and chromosomes sometimes change or have missing or extra parts. This can cause serious health conditions and birth defects in your baby. You can have tests before and during pregnancy to find out of your baby is at risk for or has certain genetic conditions and birth defects.

Clearly, genetic influences have an enormous influence on how a child develops. However, it is important to remember that genetics is just one piece of the intricate puzzle that makes up a child's life. Environmental variables including parenting, culture, education, and social relationships also play a vital role.

Geneticts also influences the birth weight, head circumferenc etc.he principal determinants of fetal growth are fetal genotype and in utero environment. Environmental factors include maternal and paternal genetics, maternal size, and the capacity of the placenta to provide nutrients to the fetus.

Factors that increase your risk of having a baby with a genetic disorder include:

• Family history of a genetic disorder
• Prior child with a genetic disorder
• One parent has a chromosomal abnormality
• Advanced maternal age (35 or older)
• Advanced paternal age (40 or older)
• Multiple miscarriages or prior stillbirth

It is important to know that some birth defects, developmental delays, and/or illnesses can be caused by prenatal exposure to drugs, alcohol, or other environmental factors.

There are several types of disorders that can be seen during pregnancy:

• Single gene disorders occur when a change in one gene causes a disease. Examples include cystic fibrosis, sickle cell anemia, Tay-Sachs disease, hemophilia, and Marfan syndrome.
• Chromosomal abnormalities occur where there are missing or extra chromosomes, or pieces of chromosomes. Down syndrome, the most common chromosomal abnormality, is caused by an extra chromosome number 21. Chromosome abnormalities can be inherited from a parent or they can happen by chance.
• Multifactorial or complex disorders are caused by a combination of genetic predispositions and environmental factors, which makes it harder to predict who may be at risk. Examples include heart defects, cleft lip or cleft palate, and spina bifida.
• Teratogenic disorders occur when the baby is exposed to substances during pregnancy that cause abnormalities, otherwise known as “teratogens.” Babies are very sensitive in the first trimester, when all of the organs are developing. Teratogens include alcohol, drugs, lead, high levels of radiation exposure, and certain medications, infections and toxic substances.