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Embryonic Stage
Week 1
Week 2
Week 3
Week 4
Week 5

Week 6
Week 7
Week 8
Week 9
Week 10
Week 11
Week 12

Week 13
Week 14
Week 15
Week 16
Week 17
Week 18
Week 19

Week 20
Week 21
Week 22
Week 23
Week 24
Week 25
Week 26

Week 27
Week 28
Week 29
Week 30
Week 31
Week 32
Week 33

Week 34
Week 35
Week 36
Week 37
Week 38
Week 39
Week 40

Pregnancy Videos & Photos - The Fourth Month

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Brought to you by Nine Months To Birth

The placental membrane allows exchanges to occur more freely between mother and fetus. The fetus grows, becomes more human-looking and tends to become more independent. The placenta: a more permeable barrier.

The placenta is now entirely functional. It takes up 20 to 25% of the area of the uterus. From the 6th month of development, it has completely replaced the corpus luteum by secreting more and more hormones; in this way, it provides mother and fetus with more estrogen and progesterone, a capacity that is specific for human beings. The fetus is now less sensitive to harmful substances than the embryo was.

Pregnancy Video: Weeks 13-16 (4th Month)

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Of Special Interest to Expecting Parents

Free Online Pregnancy Journals - Chronicle your pregnancy to share with friends & family around the world and print for your baby book!

Free Baby Stuff Second Trimester Photos Pregnancy Videos - Month 4 Pregnancy No-No's Pregnancy Blog Babies Online Toolbar	Baby Names & Meanings Free Pregnancy Wristband FREE Breastfeeding Support Kit from Enfamil 30 Free Prints from Clark Photo! Win Free Cord Blood Banking

Month 3

Monthly Pregnancy Calendar

Month 5

Your pregnancy is determined from the date of last menstral period, not date of conception. Each pregnancy, expectant mother, and unborn child is different. Your pregnancy may not progress the same as the information found here. The information here is based on the average pregnancy. It is not meant to be a replacement for any advice your may recieve from your doctor. If you have any concerns about your pregnancy, we advise you to contact your doctor.