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🌱First Trimester•Weeks 1-13
Week 4 of Pregnancy
Your baby is the size of poppy seed
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Length
0.04 inches
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Weight
Less than 1 gram
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Size Comparison
Poppy seed
👶 Baby Development
- •The embryo now consists of two distinct layers (epiblast and hypoblast) that will develop into all your baby's organs and body parts
- •The amniotic sac and amniotic fluid completely surround and cushion the embryo
- •The yolk sac provides essential nutrients until the placenta takes over in a few weeks
- •The neural tube begins forming along the back, which will become your baby's brain, spinal cord, and nervous system
- •Primitive blood vessels are forming, creating the foundation for your baby's circulatory system
- •A simple circulation system begins between the embryo and the developing placenta
💭 Common Symptoms
- •Missed period is typically the first noticeable sign of pregnancy
- •Light spotting or implantation bleeding may still occur in some women
- •Mild cramping similar to period cramps as your uterus begins expanding
- •Breast tenderness and swelling as your body produces more estrogen and progesterone
- •Fatigue and exhaustion are common as your body works hard to support the pregnancy
- •Bloating and feeling "off" as pregnancy hormones affect your digestive system
- •Frequent urination as blood flow to your pelvic area increases
🥗 Nutrition Tips
- •Folic acid (400-800 mcg daily) is absolutely crucial right now for preventing neural tube defects
- •Eat small, frequent meals every 2-3 hours if nausea or morning sickness begins
- •Include whole grains like oatmeal, brown rice, and whole wheat bread for sustained energy
- •Avoid all raw or undercooked foods including sushi, rare meat, and raw eggs
- •Eat ginger candies or drink ginger tea if you're experiencing nausea
- •Include vitamin B6-rich foods like bananas, chicken, and potatoes to help reduce morning sickness
- •Stay away from strong-smelling foods that might trigger nausea
✅ To-Do This Week
- •Take a home pregnancy test (most are accurate by the first day of your missed period)
- •Schedule your first prenatal appointment, usually around 8-10 weeks
- •Continue taking prenatal vitamins every single day without missing
- •Completely stop alcohol consumption, smoking, and all recreational drugs immediately
- •Start a pregnancy journal to document your symptoms and experiences
- •Calculate your estimated due date (40 weeks from your last menstrual period)
- •Research prenatal care providers and birthing options in your area
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Did You Know?
By the end of week 4, you can get a positive pregnancy test as hCG levels reach 25-50 mIU/mL, the threshold most tests can detect. The hormone doubles every 48-72 hours in early pregnancy!