This patient support community is for discussions relating to pregnancy concerns for teens, ages 13-17. Please note, this community is not intended to discuss how to conceive. Questions regarding this will be removed.
Pregnancy Week by Week: Week 4...
Week 4
Breaking the ovulation cycle!
What Is Happening To Your Body
At week 4 of your pregnancy, implantation is still taking place. You will begin to produce higher levels of the hormones estrogen and progesterone, which will cause many of the changes in your body throughout the rest of the pregnancy.
At about 6 to 12 days after fertilization, your HCG levels will be high enough to be detected in a home pregnancy test. If the test is positive, schedule an appointment with your health care provider to confirm the results. You may also experience the typical signs of pregnancy, including fatigue, frequent urination, breast pain and morning sickness.
What Is Happening To Your Baby
The cells in the embedded blastocyst begin to differentiate, or specialize, into distinct layers which later undergo further differentiation. One such layer undergoes a process known as gastrulation in which it further differentiates into three layers that will form the baby’s organs and tissues (the ectoderm, endoderm, and mesoderm). At this point, your baby is roughly the size of a poppy seed.
In the late stages of week 4 or early stages of week 5, tiny arms and legs, called buds, begin to develop, although they are not yet visible.
What Is Happening This Week? 
