Fetal development

Pre-embryonic timeline

0-2 weeks

Big events for pre-embryonic

Fertilization → implantation

Fertilized egg implantation site

Upper uterus

A patient is bleeding/cramping during the pre-embryonic stage. What are the implications of this?

Signal early loss or ectopic pregnancy

Embryonic timeline

2 - 8 weeks

Embryonic stage big event

Organogenesis - all major body organs and external structures begin to form

At what stage is folic acid supplementation critical?

Embryonic stage

At what stage is the baby at the highest vulnerability to teratogens?

Embryonic stage (2-8 weeks)

Fetal stage timeline

9 weeks to birth

When is a fetus considered viable? Why?

21-24 weeks

Surfactant production begins in the lungs

During which week is a pregnancy considered full term?

38 weeks

When is fundal height measured? What is the measurement supposed to be?

20 weeks gestation

20 cm

What is fundal height used for?

It is a reliable determination of gestational age from 20 weeks until approximately 36 weeks

Abnormal fundal height could suggest abnormal ___ ___ and ___ ___ levels.

fetal growth; amniotic fluid

When is the 1st, 2nd, and 3rd trimester?

1st - 1 to 13 weeks

2nd - 13 to 28 weeks

3rd - 28 weeks to birth

What does the hormone hCG do?

Preserves the corpus luteum (progesterone) until the placenta takes over by the end of the first trimester (7-10) weeks

What does the hormone hPL do?

Modulates fetal and maternal metabolism, develops breasts for lactation, decreases insulin sensitivity for the mom so that the baby has a steady glucose supply for growth

What does progesterone do?

Known as the “hormone of maintenance”, it maintains uterine lining and decreases uterine contractility

What does estrogen do?

Estrogen enlarges the breasts, uterus, and stimulates contractions

What does relaxin do?

Relaxin causes relaxation of pelvic ligaments and it softens the cervix

Which placental complication is described as painless, bright-red vaginal bleeding?

Placenta privia

What is placenta previa?

When the placenta covers all or some of the opening of the cervix, leading to painless, bright-red vaginal bleeding during the second or third trimester

What is IUGR? What causes it?

Intrauterine growth restriction - condition where the baby in the womb is not growing at the expected rate

Placental insufficiency

What placental complication is characterized by severe abdominal pain, dark red bleeding, and fetal distress caused by premature separation of the placenta?

Placental abruption

What is umbilical cord compression? What is a sign of it?

The cord is compressed, poses a risk of decreased oxygen delivery/hypoxia

Variable decelerations

What can cause cord compression?

Oligohydramnios, or too little amniotic fluid

What risks are associated with oligohydramnios?

Cord compression, musculoskeletal deformities, and pulmonary hypoplasia (lungs are abnormally small/underdeveloped at birth)

What is polyhydramnios? What risks does it pose?

Too much amniotic fluid

Maternal diabetes, neural tube defects, GI obstructions (in the fetus)

What is PDA? What are the signs of it?

Patent Ductus Arteriosus - shunt between aorta and pulmonary artery fail to close after birth;

Heart murmurs, respiratory distress, poor feeding, cyanosis

What medicines are used to treat PDA?

NSAIDS like ibuprofen and indomethacin

What is ASD?

Atrial Shunt Defect - inside the heart between the left and right atria

What is nuchal cord? What risks does it pose?

Umbilical cord is wrapped around the neck

Risk for hypoxia

What is umbilical cord prolapse?

Cord slips into birth canal before the baby does

THIS IS AN EMERGENCY

A baby is showing signs of cyanosis, heart murmur, respiratory distress, and poor feeding. What is likely the cause?

Defects such as PDA, VSD, and ASD.

You have given a baby suffering from PSD ibuprofen to help. What must you monitor for?

GI bleeding, urine output, creatinine levels, platelet counts - NSAIDs get in the way of all of these things because they suppress prostaglandins.