Home > Pregnancy Week By Week > 4 Weeks Pregnant
In week 4, majority of women notice they have miss their period and find out there are pregnant. The baby now is developing three layers ectoderm, endoderm, and mesoderm that will help with the developing of the organs. The ectoderm helps develop the baby’s nervous system.
The endoderm develops into the gastrointestinal tract, liver, pancreas, and thyroid. The mesoderm develops into the connective tissue, blood system, muscles, skeleton and urogenital system. |
During the fourth week of pregnancy your blood supply increases. The increase supply of blood helps the baby receive enough blood for himself. Many women will complain of needing to pass more urine during early pregnancy.
Since your kidneys are working a bit harder it leads to frequent urination. At week 4 your heart is also working a lot harder to pump additional blood for the baby. You might feel dizziness and tiredness from your body working so hard. |
To detect pregnancy during the first trimester a transvaginal ultrasound is performed. |
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Another way to test your pregnancy is using a home pregnancy test. The baby is too small to be deductible on an ultrasound at week fourth.
At week fourth, you might not experience any symptoms. Frequent early pregnancy symptoms are morning sickness, nausea, gas, bloating, mood swings, cramping, diarrhea, and enlargement of breast, heartburn, and constipation.
Many women experience these additional symptoms during the fourth week:
There are other early symptoms to watch out for during
your pregnancy that may imply serious complications.
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