25th week of pregnancy: what is the baby doing and what changes occur?

By (embryologist).
Last Update: 07/19/2023

The first week of the seventh month of pregnancy corresponds to week 25. Therefore, this week is part of the third trimester of pregnancy.

Progesterone causes slower digestion and incomplete closure of the stomach inlet valve. As a result, the pregnant woman may experience heartburn and gastric reflux due to the rise in stomach acid. In addition, gas accumulation is more common in the 25th week of pregnancy. The fetus continues to grow and its size at week 25 can be compared to that of a broccoli.

What changes occur in the mother?

The baby continues to grow rapidly and, as a result, so does the belly in the 25th week of pregnancy. The height of the uterine fundus, that is, the distance between the pubis and the uterus, is about 25 cm.

As pregnancy progresses, the center of gravity of the mother-to-be's body changes and moves more forward so that she can walk more easily. In addition, it is important to maintain a good posture to avoid back pain.

The pregnant woman will certainly feel at week 25 that her hair is better than ever, shinier and fuller. This is because less hair falls out during pregnancy due to the action of androgenic hormones. For this same reason, the amount of body hair may have increased or even appear in areas where you did not have it before. Once delivery has passed, hair growth will return to normal.

Maternal symptoms in the 25th week of pregnancy

One of the most repeated discomforts, once the initial nausea has passed, is reflux. As the weeks of pregnancy pass, there is a greater increase in uterine size. This compresses the stomach which, together with the increase in progesterone levels, produces the uncomfortable heartburn.

Other common symptoms in the 25th week of pregnancy are gas, both due to slowed intestinal transit and compression of the intestine. For this reason, pregnant women are advised to avoid eating heavy meals, not to drink carbonated beverages and to rest after meals sitting down, not lying down.

In addition to reflux and flatulence, other typical discomforts in the 25th week of pregnancy may include constipation, chloasma, stretch marks, leg cramps, hemorrhoids, etc. All of these symptoms will also appear in the 25th week of a twin pregnancy.

Changes in the fetus at 25 weeks

The main changes in the fetus in the 25th week of pregnancy are that the ossification nuclei located inside the bones begin to harden. Therefore, its skeleton becomes more consistent.

The baby's skin is wrinkled and its head will be covered with hair, although it will not be the definitive hair it will be born with. During this week the small teeth are placed in position below the gums and the ear is also developing above the rest of the senses.

When the end of the 25th week is reached, the fetus is about 33 cm long (taking into account the length of the legs) and will weigh about 700-800 grams on average.

If the fetal weight is between 470 and 1,075 grams, there is no need to be alarmed, since it is within the values considered normal.

What to do in the 25th week of pregnancy?

If it has not been done in the 24th week of pregnancy, it would be advisable to perform the second trimester blood test before the 28th week, as well as screening for gestational diabetes. In addition to diagnostic tests at this time of pregnancy, the expectant mother should also take some precautions during the 25th week:

  • Drink plenty of fluids to help with hydration.
  • Practice relaxation techniques.
  • Avoid wearing tight clothing.
  • Walking with comfortable shoes.
  • Take chamomile, green anise or fennel infusions to reduce gas, as well as malavisco infusions for heartburn.

In addition to all these tips, long periods of standing should also be avoided to combat the appearance of varicose veins. It is also advisable to sleep with the legs elevated and to practice moderate exercise adapted to pregnancy.

FAQs from users

How long is the fetus at 25 weeks from head to buttocks?

By Marta Barranquero Gómez B.Sc., M.Sc. (embryologist).

The length of the fetus in the 25th week of pregnancy is approximately 22 cm if the legs are not taken into account. Otherwise, the fetus could be up to approximately 33 cm long.

Is it normal to have contractions in the 25th week of pregnancy?

By Marta Barranquero Gómez B.Sc., M.Sc. (embryologist).

In the twenty-fifth week of pregnancy, Braxton Hicks contractions may appear. These contractions are different from those that happen before giving birth, as they are irregular and do not increase in intensity.

The pregnant woman may feel a slight pain when her belly becomes hard, but it disappears after a short time.

Does the fetus move a lot in the 25th week of pregnancy?

By Marta Barranquero Gómez B.Sc., M.Sc. (embryologist).

Yes, by the 25th week of pregnancy, the fetus is capable of 20 to 60 movements every 30 minutes. Therefore, the expectant mother will also feel the fetal movement even at night, which may cause difficulty sleeping.

Suggested for you

As we have indicated, week 25 is the first week of the sixth month of pregnancy. Therefore, you may find it interesting to read the following article to get a general idea of the changes that will take place during this month: Seven months of pregnancy: symptoms and development of the baby.

In addition, 4D ultrasound is recommended during this week. If you want to read more information about this imaging test, we recommend you visit this article: When is 4D ultrasound performed in pregnancy and what advantages does it offer?

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FAQs from users: 'How long is the fetus at 25 weeks from head to buttocks?', 'Is it normal to have contractions in the 25th week of pregnancy?' and 'Does the fetus move a lot in the 25th week of pregnancy?'.

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 Marta Barranquero Gómez
Marta Barranquero Gómez
B.Sc., M.Sc.
Graduated in Biochemistry and Biomedical Sciences by the University of Valencia (UV) and specialized in Assisted Reproduction by the University of Alcalá de Henares (UAH) in collaboration with Ginefiv and in Clinical Genetics by the University of Alcalá de Henares (UAH). More information about Marta Barranquero Gómez
License: 3316-CV

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