Content
At 4 weeks of gestation, which is equivalent to the 1st month of pregnancy, three layers of cells have already formed giving rise to an elongated embryo with a size of about 2 millimeters.
The pregnancy test can now be done, because the human chorionic gonadotropin hormone is already detectable in the urine.
Embryo development
At four weeks, three layers of cells have already formed:
- The outer layer, also called ectoderm, that will transform in the baby's brain, nervous system, skin, hair, nails and teeth;
- The middle layer or mesoderm, which will become the heart, blood vessels, bones, muscles and reproductive organs;
- The inner layer or endoderm, from which the lungs, liver, bladder and digestive system will develop.
At this stage, the cells of the embryo grow lengthwise, thus acquiring a more elongated shape.
Embryo size at 4 weeks
The size of the fetus at 4 weeks of gestation is less than 2 millimeters.
Changes in women at 4 weeks of pregnancy
Generally, the most common changes in women at 4 weeks of pregnancy are tiredness, discouragement, sore breasts, irritability and the desire to cry, which is normal due to hormonal changes. If pregnancy symptoms are present and menstruation does not come, it is best to take a pregnancy test. Know how to recognize the first symptoms of pregnancy.
At this stage of pregnancy, it is very important to eat well and avoid alcoholic beverages and cigarettes, in order to reduce the risk of complications during pregnancy and for the baby to be born healthy.
Confirm which month of pregnancy you are entering your details here:
Your pregnancy by trimester
To make your life easier and you don't waste time looking, we've separated all the information you need for each trimester of pregnancy. What quarter are you in?
- 1st Quarter (from the 1st to the 13th week)
- 2nd Quarter (from the 14th to the 27th week)
- 3rd Quarter (from the 28th to the 41st week)