Week 4 of Pregnancy - FamilyEducation

Week 4 of Pregnancy

First Trimester

Your 4th Week

This week, you'll need a little patience as you wait, wonder, and hope.
Implanted embryo in uterus
Implanted embryo
1. The uterine lining secretes hormones that help to support the pregnancy.
2. Chorionic cavity
3. The yolk sac is forming. It will nourish the embryo until the placenta starts functioning and make blood cells until the liver can do this.
4. The placenta starts to develop here. Soon the cells will penetrate the lining of the uterus.
5. The embryo consists of just two layers of cells that will divide very rapidly to form the beginnings of the baby's body.
6. The amniotic cavity, which later becomes the fluid-filled amniotic sac that protects the baby, develops from this area.
The uterine lining secretes hormones that help to support the pregnancy.Chorionic cavityThe yolk sac is forming.The placenta starts to develop here.The embryo consists of just two layers of cells that will divide very rapidly to form the beginnings of the baby's body.The amniotic cavity
The embryo-to-be, now securely implanted in the lining of your uterus, is starting to develop. Although you could do a home pregnancy test this week, you may end up disappointed or uncertain because at this stage a definite result is unlikely. It can be nerve racking, wondering if an unwanted period is about to arrive and dash your hopes. Talk to your partner and share your feelings with him-he may be anxious, too.

You are 3 Weeks and 1 Day Pregnant

Your baby todayThis is a cross section of the ball of cells embedded in the uterus at this early stage of pregnancy. It contains fluid in the center and two areas of white cells with a darker streak of cells between them-these will form the embryo, now less than 0.5 mm long. read more

You are 3 Weeks and 2 Days Pregnant

Your baby todayIn this computer-generated image the entire blastocyst can be seen embedded in the lining of the uterus. The cells that will develop into the embryo are seen as the dark area in the 12 o'clock position. read more

You are 3 Weeks and 3 Days Pregnant

Your baby todayThe embryo is implanted and is 10 days old. The entry point at which the embryo buried into the lining of the uterus is now covered by a clot, and this prevents blood loss and protects the embryo. read more

You are 3 Weeks and 4 Days Pregnant

Your baby todayTo embed itself in the lining of the uterus, the embryo-to-be needs the help of progesterone, secreted after ovulation by the empty egg follicle, the corpus luteum (shown in pink in this cross section of an ovary). Progesterone helps the lining thicken. read more

You are 3 Weeks and 5 Days Pregnant

Your baby todayThe first stage of placental development-your baby's life support system-is shown here. The image shows nuclei (blue) within a continuous network of cells that will become the placental villi. At first the tiny villi are solid; later, they will contain blood vessels. read more

You are 3 Weeks and 6 Days Pregnant

Your baby todayThis microscope view of an embedded blastocyst shows the amniotic cavity (semicircular white area at top), with the cells that will develop into the baby just below (dark oval at the 12 o'clock position). The yolk sac is the pink area below. read more

You are 4 Weeks Exactly Pregnant

Are you feeling irritable and tired, and are your breasts tender? Well, you might just be pregnant! read more