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Home > Be Healthy > Health Library > Week 12 of Pregnancy: What's Going On Inside
Congratulations, you've made it through your first trimester! You can now hear your baby's heartbeat with a Doppler heart monitor. That can be very exciting.
Inside your uterus, an important organ called the placenta has formed. The placenta's main job is to give your baby oxygen and nutrients through the umbilical cord.
Wondering what your baby looks like now? As you enter the fourth month of pregnancy, your baby is about the size of a plum. Average baby length is 61 mm (2.4 in.).
Here are some of the important facts and developments around 12 weeks.
Current as of:
June 16, 2021
Author: Healthwise StaffMedical Review: Adam Husney MD - Family MedicineKathleen Romito MD - Family MedicineWilliam Gilbert MD - Maternal and Fetal Medicine
Current as of: June 16, 2021
Author: Healthwise Staff
Medical Review:Adam Husney MD - Family Medicine & Kathleen Romito MD - Family Medicine & William Gilbert MD - Maternal and Fetal Medicine
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