Your Baby's Development Week 4

Week 4
Two weeks after conception, your baby is now an embryo. Now implanted into the uterine wall, the embryo will start to split into two groups. One group will form the placenta and the other will develop into your baby. At this early stage of your pregnancy the embryo is rapidly growing, from 1.5mm at the beginning of the week to 5mm by the end of week.

Pregnancy Tip
	Your body needs more of certain nutrients during the first trimester. That's why Biotegrity's Stage 1 have been formulated with increased amounts of folic acid and B12, both of which promote the healthy development of your baby during the early stages of pregnancy.

The Embryo
The embryo consists of three different layers. The inner layer, known as the endoderm, will develop into your baby's lungs, liver, and digestive system. The middle layer, called the mesoderm, will eventually be your baby's bones, muscles, kidneys, sex organs, and heart. Finally, the ectoderm, or outer layer, will make up your baby's tissues and organs such as the skin, hair, eyes, and nervous system.

Should the embryo fail to find a secure place to implant itself, the fertilized egg will pass out with your next period, which you would have been expecting at the end of this week. In many cases, this may happen without your ever having known that you were pregnant. It also also quite common; about 75% of pregnancies end within the first two weeks. In other cases, when implantation has taken place, the embryo has come loose from the uterine wall; you may experience a heavy period, sometimes lasting up to 10 days. This is a miscarriage in the most basic form. Try and avoid eating soft cheeses, pate and smoked or raw seafood. This is because many of these carry listeria, which is a bacteria that can cause fetal damage or lead to a miscarriage.

A maternal blood or urine test this week would show a positive result because the embryo is secreting human Chorionic Gonadotropin (hCG), the pregnancy hormone. Home pregnancy tests, which test for hCG in the urine, may show a positive result but are not as accurate as blood tests this early in pregnancy. Due to these new hormones, you may start to feel the first few symptoms of pregnancy, which are similar to those that you would normally be feeling when expecting your period (i.e. tender/swollen breasts, cramping, mood swings and fatigue).

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Select a week of development to read detailed information:

Week 1	Week 11	Week 21	Week 31
Week 2	Week 12	Week 22	Week 32
Week 3	Week 13	Week 23	Week 33
Week 4	Week 14	Week 24	Week 34
Week 5	Week 15	Week 25	Week 35
Week 6	Week 16	Week 26	Week 36
Week 7	Week 17	Week 27	Week 37
Week 8	Week 18	Week 28	Week 38
Week 9	Week 19	Week 29	Week 39
Week 10	Week 20	Week 30	Week 40

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