Week 3 of Pregnancy
First trimester
For informational purposes only. This page is not medical advice. Every pregnancy is different — always consult your doctor, midwife, or healthcare provider for guidance specific to your situation. In an emergency, call your provider or 911 immediately.
Baby is
about the size of a poppy seed
0.1 inches · less than 1 gram
Baby this week
- •Blastocyst is implanting into the uterine lining (a process that takes about a week)
- •Cell division is rapidly accelerating
- •The placenta is beginning to form
- •Your baby is becoming a multilayered structure preparing for major development
You this week
- •You may not feel any symptoms yet—many don't at this stage
- •Possible light spotting or cramping as implantation occurs (this is normal)
- •Breast tenderness may begin or intensify
- •Fatigue, though you might attribute it to other causes
- •Mood changes or heightened emotions
This week's tips
- •If you haven't already, start taking prenatal vitamins with folic acid daily—this is crucial for neural development
- •Avoid known pregnancy risks: alcohol, smoking, unprescribed medications, and high-heat environments
- •Stay hydrated and eat nutrient-rich foods when you can, even if nausea hasn't hit yet
- •Keep taking care of yourself as you normally would—moderate exercise and stress management are beneficial
- •If you suspect you're pregnant, wait until at least the end of this week to test for the most accurate result
Informational only — always check with your doctor or midwife for advice specific to you and your baby.
Looking ahead
By next week, your baby will be officially considered an embryo, and major organ systems will begin forming. You may also start noticing more pregnancy symptoms as hormones increase.
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For informational purposes only. This page is not medical advice. Every pregnancy is different — always consult your doctor, midwife, or healthcare provider for guidance specific to your situation. In an emergency, call your provider or 911 immediately.
This content is for informational purposes only and is not medical advice. Every pregnancy and baby is different. Always consult your doctor, midwife, or pediatrician for guidance specific to your situation.
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