Placenta & Umbilical Cord
The placenta forms in early pregnancy and acts as baby's life support system, delivering oxygen and nutrients through the umbilical cord.
Development Timeline
Weeks 2-40 (fully functional by week 12)
Overview
The placenta is an incredible temporary organ that develops specifically to support your baby during pregnancy. It begins forming at implantation (around week 2) and takes over hormone production from your ovaries around week 10. The placenta acts as lungs, kidneys, liver, and digestive system for your baby all in one.
The umbilical cord connects your baby to the placenta and typically contains three blood vessels: two arteries carrying deoxygenated blood and waste from baby to placenta, and one vein carrying oxygenated blood and nutrients from placenta to baby. The cord grows as baby grows, reaching about 20 inches in length.
The placenta is highly efficient, allowing oxygen, nutrients, and antibodies to pass from you to baby, while keeping most harmful substances separate. However, some things like alcohol, certain medications, and nicotine can cross the placental barrier, which is why avoiding them is crucial during pregnancy.
🗓️ Week-by-Week Milestones
Placenta begins forming at implantation site
Placenta producing hCG hormone (pregnancy hormone)
Umbilical cord connecting baby to placenta
Placenta takes over hormone production from ovaries
Placenta fully functional as life support system
Placenta position assessed on anatomy scan
Placenta reaches maximum size, weighs about 1.5 pounds
👀 What to Expect
- •Placenta delivers 5-30 minutes after baby is born
- •You'll have mild contractions to help placenta separate
- •Doctor examines placenta to ensure it's complete
- •Umbilical cord typically 20 inches long at birth
- •Cord may be wrapped around baby - usually not problematic
- •Placenta weighs about 1-1.5 pounds at birth
💡 Tips for Parents
- ✓Placenta position (anterior vs posterior) affects when you feel movements
- ✓Low-lying placenta (placenta previa) usually resolves as uterus grows
- ✓Umbilical cord has no nerve endings - cutting it doesn't hurt baby
- ✓Delayed cord clamping allows baby to receive more blood from placenta
- ✓Placenta delivers after baby (third stage of labor)
- ✓Some families save cord blood for potential future medical use
- ✓Placenta position is noted on ultrasound reports
✨ Amazing Facts
The placenta is the only temporary organ humans grow
It shares DNA with baby, not with mother
The placenta can grow new blood vessels throughout pregnancy
Some cultures have traditions around the placenta after birth
Identical twins may share a placenta or have separate ones
Related Development Topics
👶 Planning Ahead?
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