The second trimester of pregnancy is usually the most stable stage of pregnancy.. The mother has assimilated her new state and the fetus has already formed all her organs. Therefore, this stage almost always goes smoothly.
One of the most positive aspects of the second trimester of pregnancy is that many of the annoying symptoms that were present in the first three months begin to reduce and even disappear. The most common thing is that the nausea and dizziness are now much milder or gone.
The normal thing is that there is also more energy and less fatigue. The baby will have a noticeable increase in weight and size and the mother will feel that her pregnancy is more “real”. The second trimester of pregnancy runs from week 13 to week 27. Let’s see the details of this fantastic stage.
Changes in the fourth month

During the fourth month there is great progress in the development of the child. Your heart and circulatory system have finished forming and you can blink. Her face already looks very full and her nervous system is starting to work.
At the end of this stage, the baby It will measure approximately 13 centimeters and weigh approximately 120 grams. Let’s see in detail what happens in this phase of the second trimester of pregnancy.
week 13
The most surprising event of week 13 is that the baby is already starting to produce urine. It releases it into the amniotic fluid that surrounds it and actually absorbs some of it, which is normal. Likewise, their bones begin to harden and their movements become a little smoother.
week 14
The highlight of week 14 is this Now you can hear your baby’s heartbeat during a prenatal checkup. This is a very exciting time for most parents. Red blood cells are already forming in her spleen and her neck is more defined, as are her genitals.
week 15
At week 15, the child’s rapid growth continues. His hearing is much better developed and he is probably already starting to hear his mother’s voice and your heartbeat. The pattern of hair and scalp forms, and a fine fuzz called lanugo appears on its head. This disappears before birth. Sometimes you will have hiccups.
week 16
At 16 weeks the baby has thicker skin and a more upright head. The baby’s first movements are felt lightly, as if he is bubbling or fluttering. The extremities can now be flexed and he is able to make a fist. In fact, you can grab the umbilical cord and pull it out. You can also frown and squint.
Changes in the fifth month
During the fifth month there is a lot of progress. The senses develop and new gestures and facial movements appear which can be perceived by the mother. At the end of this phase of the second trimester of pregnancy, the baby will measure approximately 25 centimeters and weigh approximately 350 grams.
week 17
The baby already has eyelashes, eyebrows and novice fingerprints. The proportion of head size to the rest of the body begins to balance out. Toenails appear and the bones in this area begin to harden. The child is more active: he rolls and turns in the amniotic fluid. The placenta continues to grow.
week 18
By the time the 18th week is reached, the baby’s hearing is already highly developed. Hear outside sounds more clearly and even react to music or loud noises. She also has much more defined ears. Her digestive system begins to function and her eyes are better positioned on her face.
week 19
The pace of growth is no longer so intense. Her skin feels rough and is still very delicate. Here because, a layer of fat forms around the skin, the name of which is “sebaceous point”. This will protect you from any negative effects that amniotic fluid can cause. In the case of girls, the uterus and vaginal canal are formed.
week 20
At week 20 the baby already has much more coordinated movements. That’s when he starts sucking his thumb to develop their sucking reflex, which will be very useful when they are born. He also sleeps and wakes up in more or less regular patterns.
Second trimester of pregnancy: changes in the sixth month
The sixth month is from week 21 to week 27, so it’s not really a month as such. Remember that gestation time is calculated from the start date of the last period; that is, when a woman is not yet pregnant.
At this stage there are many changes. Their senses are sharpened, skin development continues and the baby acquires new skills. At the end of this phase of the second trimester of pregnancy it will measure about 30 centimeters and weigh between 600 and 900 grams.
week 21
The baby begins to differentiate the mother’s voice and recognize the voices of the people around her. It’s a good time to talk to him and sing to him. Her body is covered in a fine hair called “lanugo” which will disappear before she is born. The hair on her head and eyebrows thickens and shows shades of color.
week 22
The taste buds begin their development and the child practices swallowing. Even the lungs are advancing in their evolution and the child is already practicing breathing movements. Brown fat is being formed, which is where heat is produced. In males, the testicles begin to descend.
week 23
In week 23, ridges form on the soles of the hands and feet. It is now more common for the child to suck his thumb and their movements are already perceptible by the mother. Usually the baby rests when the mother is active and moves when she rests. All those movements are a sign that he’s fine.
week 24
The baby’s skin is translucent and appears pink or red, as it allows you to appreciate the blood in the capillaries. If he has normal movement, it is usually said that he is now “vital”. This means that if he were born at this time, he would have a chance of surviving, even if he would need a lot of help to do so.
week 25
In week 25 there are no major changes. For this moment has already developed Rapid Eye Movements (REM). This is that the eyes move quickly, even if the eyelids are closed. The digestive system and lungs have completed their formation, but are not yet considered mature.
week 26
The eyes take on a blue tint. The child exhibits vigorous movements, while accumulating more and more fat and muscle. Your skin looks a little less wrinkled. The lungs start producing a substance called “surfactant” which allows the air sacs to inflate and deflate normally.
week 27
At week 27, the second trimester of pregnancy ends. It is a time of maturation of already formed organs and weight gain. Your heart rate slows down and you can sometimes hear your heart by putting your ear to your belly.
Changes in the mother during the second trimester of pregnancy

Just as the baby undergoes changes during the second trimester of pregnancy, the mother also experiences changes in her body. The most common are the following:
- Pain in the lower abdomen.
- Backache.
- Bleeding gums.
- Breast growth.
- Braxton Hicks contractions.
- Nasal congestion and nosebleeds.
- Vaginal discharge or discharge.
- Frequent urination.
- Hair growth and thickening.
- Heachache.
- Constipation and heartburn.
- Dizziness.
- Hemorrhoids.
- Leg cramps.
- Skin changes.
- spider and varicose veins.
- Increased risk of urinary tract infections.
- Weight gain.
- Increased sex drive.
General advice for the second trimester of pregnancy
The second trimester of pregnancy is usually easier to bear than the first. Anyway, emotions may continue to fluctuate with bouts of anxiety, sadness, or both. It is normal for this to happen, but if it is very pronounced, it may be a good idea to seek psychological support.
During this phase, the following actions should be performed:
- Keep taking your prenatal vitamins.
- Get adequate exercise regularly.
- Perform Kegel exercises regularly.
- Maintain a healthy diet, rich in fruits, vegetables, fiber and lean proteins.
- Hydrate frequently.
- Keep your teeth and gums healthy. Inadequate oral hygiene is associated with preterm labor.
The consumption of any substance that may affect the child, such as tobacco, alcohol, etc., should be avoided. It is very convenient to start a prenatal education course at this stage.as this provides valuable information and facilitates the assimilation of the changes that the mother is experiencing.
It is important that routine checkups are scheduled and adhered to. The indicated thing is to do the appropriate ultrasound and a glucose test. A prenatal genetic screening test and appropriate vaccinations should also be performed.
Enjoy your second trimester of pregnancy
The second trimester of pregnancy is the right time to shop for maternity clothes. This should be comfortable and take into account your belly growth during the rest of your pregnancy. It’s also a good idea to take lots of souvenir photos.
It is best to sleep on your side for better rest. It’s also a good idea to start planning for the inevitable baby shower. It can also be a great time to take one last “honeymoon” or “baby moon” trip with your partner.
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