Understanding Teratogens and Prenatal Health

Teratogens 🚨

Teratogens are substances or agents that can cause harm or damage to a developing fetus or embryo, resulting in birth defects, brain damage, intellectual impairment, or behavioral issues.

Examples of Teratogens

• Alcohol

• Prescription medication

• Over-the-counter medication

• Cigarettes and other tobacco products, vaping

• Illegal drugs

• Pollution

• Viruses and bacteria

• Food-borne illnesses

• Radiation (X-rays)

Genetic Vulnerability

Timing of teratogen exposure is critical, and the same teratogen may cause irreparable damage at one stage of pregnancy but have no effect at another stage. Frequency and duration of exposure also play a role.

Reducing Teratogen Risks

• General good maternal health before pregnancy is a protective factor

• Good nutrition and health habits during pregnancy

• Start prenatal health care as early as possible

• Avoid use of alcohol, tobacco, illegal drugs

• Consult your doctor regarding any prescription drugs you are already on and before taking any new ones, as well as before taking over-the-counter medicines or herbal remedies

• Follow doctor's advice on any foods or activities to avoid

The Beginning of Life 🌱

All living things are composed of cells that promote growth and sustain life according to instructions in their molecules of DNA.

DNA (Deoxyribonucleic acid)

Chromosomes

Conception

When sperm and ova unite and fertilization occurs, a zygote is formed. Zygotes have 23 chromosomes from each parent, resulting in a total of 46 chromosomes.

The Human Genome Project 🧬

The Human Genome Project is a research study that aimed to sequence and map all of the genes in human DNA.

Interesting Data

• Genetic similarity between any two humans (regardless of ethnicity, gender, or race): 99.5%

• Genetic similarity between humans and any mammal: 90%

Genetic Variations and Similarities 🌈

Humans have approximately 23,000 genes. This means that while many genes are identical for all humans, some genes have variations.

Allele

Effects of Variations

Effects of variations vary greatly, from having no detectable effect at all to causing observable physical differences to causing life-threatening diseases.

Genetics 🧬

Genotype

Phenotype

The 23 Pairs of Chromosomes 🧬

Humans should possess 46 chromosomes (however, chromosomal errors can occur). 44 of them are considered autosomes, and the remaining 2 are sex chromosomes (XY for male, XX for female).

Sex Determination

The sex of offspring is determined by whether the ovum is fertilized by the father's X sperm or his Y sperm.

Gender Differences in Vulnerability 🚨

Males are genetically more vulnerable than females. Many genetic disorders are X-linked disorders, meaning they are related to the X chromosome.

X-Linked Disorders

• Color blindness

• Hemophilia

• Duchenne's Muscular Dystrophy

• Allergies

• Some learning disabilities

• Some vision disorders

Genetic Expression 🧬

Just because a gene is present does not mean it will be expressed. The majority of traits are polygenic, meaning that more than one gene is involved.

Regulator Genes

Dominant Recessive Heredity 🧬

Dominant genes are more influential than recessive genes. A dominant gene can completely control the phenotype with no noticeable effect of the recessive gene.

Carrier

Twins 👶

Types of Twins

Prenatal Development 🤰

Three Periods of Prenatal Development

1. Germinal Period (first 14 days)

2. Embryonic Period (3-8 weeks)

3. Fetal Period (9 weeks-birth)

Vulnerability During Prenatal Development

Prenatal Testing 🧬

Many prenatal tests are done during pregnancy to identify and prevent potential issues.

Examples of Prenatal Tests

• Vaccinations and immunity levels

• Blood and urine tests

• Ultrasound

• Amniocentesis

• Glucose testing

Chromosomal Anomalies 🚨

The majority of chromosomal issues cause the embryo to stop developing very early and result in miscarriage.

Examples of Chromosomal Anomalies

• Down Syndrome (also called trisomy-21)

• Other chromosomal anomalies (too many or too few chromosomes)

Genetic Disorders 🧬

The phenotype is only affected if the gene is dominant or if both parents carry the recessive gene.

Examples of Genetic Disorders

• Huntington's disease

• Cystic fibrosis

• Thalassemia

• Sickle cell disease

• Fragile X syndrome

Preterm Versus Small for Gestational Age 🤰

Low Birthweight 🚨

Infants with low birthweight will be classified into three categories: low, very low, and extremely low.

Factors Contributing to Low Birthweight

• Chronic maternal health issues

• Maternal illness during pregnancy

• Exposure to teratogens, especially tobacco products

• Maternal use of certain prescription medications

• Maternal illegal drug use before or during pregnancy

• Low SES

• Lack of prenatal care

• Chronic stress

Consequences of Low Birthweight

• All developmental accomplishments are late

• Cry more, have attention issues, behavioral issues, language delays, learning disabilities

• By middle childhood, they continue to have neurological delays and smaller brain volume## 🤰‍♀ Trends in Maternal and Infant Health

Why Does the US Do Poorly in Maternal and Infant Health?

The US has the highest unplanned pregnancy rate in the developed world, which contributes to poor maternal and infant health outcomes. Several factors contribute to this issue:

• Lack of comprehensive sex education: Many individuals in the US do not receive adequate education on sex and reproductive health.

• Lack of education regarding birth control usage: Limited knowledge about birth control options and how to use them effectively contributes to unplanned pregnancies.

• Lack of availability and affordability of more reliable forms of birth control: Access to effective birth control methods is limited for many individuals in the US.

Teen Pregnancy Rates

The US has the highest teen pregnancy rate in the developed world. Although the rate has been declining over the past decade, it remains a significant concern.

General Health Care Access

Limited access to general health care contributes to poor maternal and infant health outcomes in the US. This includes:

• Lack of general health care access: Many individuals in the US do not have access to regular health care, leading to unmanaged health conditions.

• Lack of maternity health coverage: Limited access to health insurance that covers maternity care contributes to poor health outcomes.

• Lack of prenatal health care: Inadequate prenatal care can lead to complications during pregnancy and childbirth.

• Lack of pregnancy-related hospital services and doctors in rural areas: Limited access to medical care in rural areas can lead to poor health outcomes.

Maternity Leave

The US is the only developed country without maternity leave, which can contribute to poor health outcomes for new mothers and their infants.

🏥 Medical Interventions

Fetal Monitoring

Fetal monitoring is used to track the health of the fetus during labor and delivery.

Epidurals

Epidurals are a type of pain relief used during labor.

Induced Labor

Induced labor is a medical intervention used to stimulate labor.

Cesarean Sections (C-Sections)

A Cesarean section is a surgical birth where the fetus is removed through a lower abdominal incision.

👶 Newborns

Brazelton Neonatal Behavioral Assessment Scale

The Brazelton Neonatal Behavioral Assessment Scale records 46 behaviors, including 20 reflexes.

Examples of reflexes include:

• Sucking

• Rooting

• Grasping

Bonding between Mother and Child

Bonding between mother and child is especially important. Kangaroo care, or skin-to-skin contact, can help with this, particularly with preterm infants.

🤕 New Mothers

Postpartum Depression

New mothers are at risk for postpartum depression, which can be influenced by:

• Physical problems after birth, especially after a C-section

• Psychological symptoms, ranging from the normal baby blues to serious depression to postpartum psychosis

• Struggles with adequate baby care/lack of help

• Previous mental health issues

• Infant health problems

• Lack of sleep