Prenatal Development

Prenatal Development

We all start off as a tiny cell the size of a “.”

9 months later we are compromised of trillions of cells

There are several things happening the first 9 months of our lives that influence development the rest of our lives

How does age affect fertility?

• more and more people are delaying having children until their late 30s or 40s

• as you age so do ur ovaries and the eggs inside them

• you cannot see or feel these changes, and they happen faster than you might think

• prime fertility = late teenage yrs-late 20s

How does age affect the eggs?

You begin life with a fixed number of eggs in your ovaries. The # of eggs decreases as you get older

What are the chances of pregnancy as you get older?

• for healthy couples in their 20s and early 30s, around 1 in 4 women will get pregnant in any single menstrual cycle

• by age 40, 1 in 10 women will get pregnant per menstrual cycle

What are some possible risks of getting pregnant late in life?

When you get pregnant later in life, there is a higher risk of complications

But these risks don’t all increase at once

Some risks do not increase until age 40 or later

Why does the risk of pregnancy increase with age?

Older people tend to have more health problems than younger people

• for example, high blood pressure is more common in older people

• having high blood pressure before pregnancy can increase the risk of preeclampsia

Risks before conception

Women:

• alcohol

• drugs

• caffeine

• over-the-counter medications

• herbs

• prescriptions

• (many have detrimental effects in the first weeks of pregnancy)

• get appropriate vaccines

Teratogens

any environmental influence that can cause prenatal damage

• ex: medications for seizures, migraines, obesity, acne, bipolar disorder,,,

• impact: can cause pregnancy loss, birth defects, or long-term health complications

What is a risk factor?

• A factor that increases the probability of a negative outcome

• does not predict the outcome 100%, merely places the fetus at a higher risk of problems

• Teratogens are risk factors for outcomes - they do NOT guarantee an outcome will occur

What are the 6 Main Principles of Teratogens

1. susceptibility depends on the developmental stage at the time of exposure

2. Teratogens are likely to affect a specific organ

3. Individuals vary in their susceptibility to teratogens (ex: genetic predispositions coupled with environmental exposure might increase risk level)

4. Susceptibility depends on the mother’s physiological state

5. The greater concentration of the teratogen the greater the risk

6. some teratogens have minimal effect on the mother, but major effect on the fetus

Research on teratogens (by researchers at the University of Florida)

Researches 3.4 million pregnancies from a national insurance database (2006-2017)

1 in 16 women were exposed to harmful teratogenic drugs during pregnancy

Findings on Teratogenic Drug Exposure

Definite Teratogens: Exposure decreased from 1.9% to 1.2%

Potential Teratogens: Exposure increased from 3.4% to 5.3%

High-Risk Groups: Teenagers and women in their 40s had the highest risk of exposure

FDA Amendment Act 2007

Introduced stricter regulations on high-risk drugs

Risk Evaluation and Mitigation Strategy (REMS)

Ensures safer medication use

FDA Risk Mitigation Strategies Study Findings

12 REMS-regulated drugs were used infrequently and contributed minimally to prenatal exposure

Implications and Recommendations

For Healthcare Providers:

• review all medications with pregnant patients

• educate about teratogens risks and safer alternatives

For Women of Childbearing Age:

• consult providers before taking any medication

• consider effective contraception if taking teratogenic drugs

• read medication labels and warnings carefully

Genes

are specific sequence of nucleotides and are recipes for making proteins

• Genes are located on the chromosomes and there are an

  estimated 20,500 genes for humans

Mitosis

the cell's nucleus making an exact copy of all the chromosomes and splitting into two new cells

genotype

the sum total of all the genes a person inherits

phenotype

the features that are actually expressed

polygenic

meaning they are the result of several genes.

Sickle Cell Disease

is a condition in which the red blood cells in the body are shaped like a

sickle (like the letter C) and affect the ability of the blood to transport oxygen.

Cystic Fibrosis

is a condition that affects breathing and digestion due to thick mucus building up

in the body, especially the lungs and digestive system.

Phenylketonuria (PKU)

is a metabolic disorder in which the individual cannot metabolize

phenylalanine, an amino acid. Left untreated intellectual deficits occur.

Behavioral Genetics

scientific study of the interplay between the genetic and environmental contributions to behavior.

Often referred to as the nature/nurture debate,

zygote

It is typically fertilized in the top section of the fallopian tube and

continues its journey to the uterus. This cell, containing the combined genetic information from both parents

embryo

Upon implantation this multi-cellular organism is called an embryo.

Starting the third week the blastocyst has implanted in the uterine wall.

placenta

a structure connected to the uterus that provides

nourishment and oxygen from the mother to the developing embryo via the umbilical cord.

fetus.

From the ninth week until birth, the organism is referred to as a

age of viability

The first chance of survival outside the womb

Ultrasound

one of the main screening tests done in combination with blood tests. The ultrasound is a test in which sound

waves are used to examine the fetus.

Amniocentesis

a procedure in which a needle is used to withdraw a small amount of amniotic fluid

and cells from the sac surrounding the fetus and later tested

The First Stage of Delivery

begins with uterine contractions that may initially last about 30 seconds and be spaced 15 to 20 minutes

apart. These increase in duration and frequency to more than a minute in length and about 3 to 4 minutes apart. Typically,

doctors advise that they be called when contractions are coming about every 5 minutes.

The Second Stage of Delivery

involves the passage of the baby through the birth canal (Figure ). This stage takes about 10–40 minutes. Contractions usually come about every 2–3 minutes. The mother pushes and relaxes as directed by the medical staff.

Normally the head is delivered first. The baby is then rotated so that one shoulder can come through and then the other shoulder.

The Third Stage of Delivery

is relatively painless. During this stage, the placenta or afterbirth is delivered

Anoxia

is a temporary lack of oxygen to the brain