Changes in the baby and common discomforts in the 33rd week of pregnancy

By (embryologist) and .
Last Update: 02/24/2023

If the pregnant woman is in the 33rd week of gestation, she is in the third and last trimester of pregnancy. As a result, your belly will already have a considerable size that can make it increasingly difficult to carry out your daily routine.

The baby continues to grow and, as the weeks go by, has more limited space in the uterus. This means that their movements are perceived by the mother with intensity. In addition, the baby may have already turned around and is in cephalic presentation, with the head toward the maternal pelvis, preparing for the moment of birth.

What does the baby look like in the 33rd week of pregnancy?

In the 33rd week of pregnancy, the baby's appearance is already very similar to what it will look like when the mother holds it in her arms and sees its little face for the first time. Its length is now around 43 cm and its weight is just under 2 kg.

However, the baby still has to grow and gain weight until the time of birth, which is contributed to by the fat that accumulates under the skin. This fat will help you maintain your body temperature once you are born.

The baby is asleep for a large part of the day and has rapid eye movement(REM) phases and may even dream. Its pupils already react to the change in light if a light source approaches the womb, and it is also able to hear, for example, the mother's voice.

Your lungs are preparing to breathe in the outside environment and are almost ready. The woman can feel, even from a few weeks ago, how the baby hiccups inside her womb as training for breathing.

On the other hand, it is common that in the 33rd week of pregnancy the baby is already in cephalic presentation, which means that it has already turned around and is positioned head down in preparation for delivery. If this is not the case and he presents breech, turning will become more infrequent as the weeks go by, although it is still possible.

The truth is that their movements are increasingly limited by the lack of space in the uterus. However, the woman should notice how the baby moves and, also due to the lack of space, she will certainly notice these movements with great intensity.

Changes, discomfort and symptoms in the mother

At this stage of pregnancy it is common for pregnant women to feel back pain, especially in the lower back (lumbar area), but it can extend to the buttocks, thigh and leg. This is an effect of the curvature of the back having changed due to pregnancy, which can squeeze the sciatic nerve and thus cause sciatica.

In addition, the enlargement of the uterus can cause women to have certain breathing difficulties, slower and heavier digestion and an increased urge to urinate due to the pressure of the uterus on the bladder.

On the other hand, other common symptoms in the 33rd week of pregnancy are:

  • Dry skin and itching due to the great stretching of the abdomen.
  • Heartburn and reflux.
  • Constipation and possible hemorrhoids.
  • Swelling, cramps and varicose veins in the legs.
  • Carpal tunnel syndrome, as the swelling causes the nerves to be pinched and the hands to become numb.
  • Outward navel and more pigmented linea alba.
  • Breast volume increase.
  • Possible secretion of colostrum.
  • Braxton Hicks contractions, in which the belly becomes hard. They are irregular, painless (although they can be annoying) and do not increase in frequency or intensity, unlike labor pains.

At this stage of pregnancy, a woman may already have some difficulty sleeping and resting at night. Therefore, it may be advisable to rest as much as possible during the day and use several pillows to be more comfortable.

Control and medical tests in week 33

The third trimester checkup is usually performed between the 32nd and 36th week of pregnancy. This control includes, in addition to the usual blood pressure and weight, a blood test, a urine test and an ultrasound scan.

The blood test will allow, among other things, to see if the woman has anemia and needs iron supplements. In addition, it will be used to perform coagulation tests for possible anesthesia.

A urinalysis will confirm or rule out a urinary tract infection and evaluate for protein in the urine (proteinuria), which could be indicative of a pregnancy complication called preeclampsia.

The ultrasound will be used to evaluate the growth of the baby, its position, the amount of amniotic fluid and the location and condition of the placenta.


First of all, it is important to mention that in the 33rd week of pregnancy it is still necessary to take care of your diet so that it is healthy. In addition, adequate fiber intake and good hydration will help relieve constipation and prevent the appearance of hemorrhoids.

To reduce acidity and reflux, it will be better to eat small frequent meals and avoid fried foods and very fatty or spicy foods.

If leg discomfort and swelling have appeared, physical exercise and keeping active will be of great help to alleviate them (unless contraindicated by the specialist). In addition, it is advisable to keep the legs up whenever possible.

In case of low back pain and sciatica, exercise will also be a good ally. You can also relieve the pain by putting heat on the area. If it is very intense, the specialist should be consulted if it is possible to take paracetamol.

Also, do not forget to use a moisturizing cream or specific oil to avoid itching and the appearance of stretch marks.

Finally, the woman can begin this week to wash the baby's clothes and prepare the bag that she will take to the hospital at the time of delivery. You can get help on what to include in your maternity bag in this article: What to bring in your hospital bag at delivery.

FAQs from users

What are the baby's movements like at 33 weeks of pregnancy?

By Silvia Azaña Gutiérrez B.Sc., M.Sc. (embryologist).

The baby's movements in the 33rd week of gestation may be somewhat different from those perceived in previous weeks, as the baby has less and less space inside the mother's womb. As a result, the baby's movements may feel less free and therefore more intense.

In any case, the baby should continue to move and the woman should control her movements in the manner recommended by the specialist who is managing her pregnancy. If less foetal activity is detected, you should go to the hospital so that they can check that everything is all right.

Is it possible to have sex at 33 weeks of pregnancy?

By Silvia Azaña Gutiérrez B.Sc., M.Sc. (embryologist).

Yes, you can have sex during pregnancy as long as it is a pregnancy that is progressing normally, without risks or complications.

However, there are some situations in which it is better to avoid sexual relations while pregnant. This is the case of vaginal bleeding with no known cause, a history or risk of premature birth or miscarriage, cervical insufficiency, placenta praevia, loss of amniotic fluid or multiple pregnancy.

If in doubt, it is always best to consult the specialist in charge of the pregnancy.

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FAQs from users: 'What are the baby's movements like at 33 weeks of pregnancy?' and 'Is it possible to have sex at 33 weeks of pregnancy?'.

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 Silvia Azaña Gutiérrez
Silvia Azaña Gutiérrez
B.Sc., M.Sc.
Graduate in Health Biology from the University of Alcalá and specialized in Clinical Genetics from the same university. Master in Assisted Reproduction by the University of Valencia in collaboration with IVI clinics. More information about Silvia Azaña Gutiérrez
License: 3435-CV
Adapted into english by:

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