Pregnancy Calendar

4th Week of Pregnancy


A new life is now growing inside you. Embryonic cells are dividing quickly. Less than four days after fertilization, one cell has divided into 16 cells and formed a morula which has left the fallopian tube and is traveling to the uterus. There it attaches itself to the uterine wall. By the end of week four, the tiny one-millimeter embryo resembles a tadpole. It is not yet visible on an ultrasound scan but you can notice changes in the uterine lining and a yolk sack that provides the embryo with oxygen and nutrients.

Gradually, the placenta begins to form. Between 4 to 10 weeks, your baby’s brain, backbone, and other organs will begin to form. During this time, the fetus is most vulnerable to external disruptions and its development can be easily damaged. You are due to start your period at the end of a 28-day cycle. Although some women have worked out what’s going on already, the lack of a period is generally the first symptom of pregnancy for most women.

Hormonal changes may leave you feeling tired or even exhausted. You can also experience cramping very similar to menstrual cramps, which is an indication of an expanding uterus. Some women can also experience spotting when the embryo attaches itself to the uterine wall.

If you use a home pregnancy test kit now, available from most pharmacists, it should show a positive result just a few days after the missed period. You will get an accurate answer. Use the test the first time you urinate in the morning; just follow the instructions provided with the test. If the result is negative but you are still sure you are pregnant, wait a week and try again. If the result is positive, book your first appointment at the doctor’s. It is advisable to visit a midwife or gynecologist 6-8 weeks after your last period, or 2-4 weeks after a positive pregnancy test.

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