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Pregnancy Week Calculator

Reviewed by MD Katiuska Ríos Calderón

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When did your last period start?

Table of Contents

How to Use the Pregnancy Week Calculator

To use our online simulator simply specify the date your last period started and its duration, remember to do so accurately by indicating day, month, and year.

Once you have entered the date, click on “Calculate” and our tool will give you the result in a matter of seconds in an automated and totally free way.

If you want to calculate ovulation (or you do not remember the start of your last period and want to calculate it from this) we advise you to use our fertility calculator.

How to Interpret the Calculation of Pregnancy Weeks

The delivery day should be calculated taking as a starting reference the first day of your last period, to which forty weeks must be added.

This is mainly because ovulation (and therefore conception) usually takes place a couple of weeks after menstruation begins. It will be much easier to calculate this date if the cycle is regular than if it is irregular.

Attention: we are always talking about an indicative date, that is, it is not 100% certain that the child will be born on that exact day, plus you must take into account that pregnancy can come to an end either at week 37 or at week 42, therefore, even the data of the 40 weeks is indicative.

If you want more accurate results we recommend that you put yourself in the hands of a gynecologist, he will be able to help you much better by having all the tools at his disposal and, in addition, having the possibility of establishing an individualized diagnosis.

Therefore, take the results you have obtained in our pregnancy week calculator as something indicative, not as an unchangeable reality. The content referred to here can be used as a reference and should never replace your specialist's instructions, as they can provide a more individualized follow-up of the issue and help you in a much more personalized and appropriate way.

We hope that our instructions have helped you to get oriented on your long journey towards childbirth, have resolved many of your doubts, and, above all, have indicated under what circumstances it is necessary to see a specialist.

You will now find an explanation of how your pregnancy progresses week by week, we recommend you take a look.

Pregnancy Progress Week by Week

1 weeks pregnant

Remember that the first day of your menstruation is taken as the first day of pregnancy, it is done this way to calculate the weeks of pregnancy, but obviously, you are not yet pregnant.

In this first week, you prepare for ovulation, and it is after fertilization occurs, which happens around day 1 to 14 of your cycle and in the Fallopian tube, that we could talk about pregnancy, as the gametes (egg and sperm) have joined to form a zygote that will give rise to a living being and is being gestated inside you.

Really, in this period there are still no specific symptoms.

How the body changes in the first week of gestation

As we have explained a few lines above, your body will not yet show noticeable changes. Still, your organism is beginning to prepare for the new life that is to be generated inside you.

For example, more estrogen than usual is starting to be produced which can give you an unexpected surge of energy.

What to do in week 1 of pregnancy

The first thing is to remember that there is not yet an official pregnancy and what you should do if you are thinking about getting pregnant, is to visit your doctor, he will give you more appropriate recommendations.

As an indication, we can give you a couple of tips: do not drink alcohol and avoid smoking, although these are two constant prohibitions during pregnancy it is important that you start doing so from the first day, even before if you are thinking about getting pregnant.

You can also start taking folic acid, this even about 3 months before getting pregnant.

2 weeks pregnant

During this week, you prepare for ovulation, depending on the length of your cycles, this could be between day 11 and 14.

If you have had sexual intercourse, then it is very likely that the egg has been fertilized, it quickly begins to transform, cells that at this stage are called a morula start to grow, it consists of 4 to 8 cells and it is because of its resemblance to a little blackberry that it is given that name.

Already on day 8, after conception, the morula has turned into a blastocyst and this into an embryo, which seeks to nest in your endometrium (to nestle).

After this event, an intense production of chorionic gonadotropin begins and it is because of this, that you will soon start to have nausea.

How the body changes in the second week of pregnancy

Great changes are about to start inside your body without you even realizing it, moreover, you may feel a bit of pressure in the pubis and notice a slight increase in your breasts, you could even confuse it with premenstrual syndrome.

What to do in week 2 of pregnancy

Follow the advice from the first week (neither smoke nor drink alcohol), and as pregnancy is already within your plans, start a healthy diet, if you hadn't already done so.

3 weeks pregnant

Once the third week of the 40 arrives, you will indeed start to feel some symptoms for the first time. The most common ones are: slight mood changes, drowsiness during the day, nausea upon waking, tiredness throughout the day, and breast tenderness.

All these changes are mainly caused by the hormonal transformations that your body is beginning to undergo to prevent rejection of the new baby growing inside you.

How the body transforms during the third week of gestation

A good portion of women will still not notice, even in the 3rd week, any change in their body. However, it would not be surprising if you had lost your appetite and, consequently, some weight.

We recommend you start keeping track of your weight throughout this week to know how much you are gradually gaining.

How the baby grows in week 3 of pregnancy

Consider that the baby you are carrying is growing very quickly, from 4 to 8 initial cells, there are now more than 300, and in these first weeks, they increase in size and multiply very quickly, even doubling in number each day.

4 weeks pregnant

If you have already reached the fourth week, it means that your embryo has completed the first month in your body. This is the ideal time to take a pregnancy test, as from the first month the hCG hormone will have increased enough to have an accurate result.

How the body changes in the fourth week of pregnancy

Your body is preparing to protect the embryo and due to hormones, especially estrogens, you will start to notice more vaginal secretions. The uterus is gradually increasing in size.

You might eventually notice slight blood loss, which can be caused by the embryo implanting in the endometrium.

How the baby grows during week 4 of pregnancy

Right now it can measure between 1 and 1.5 cm and its weight may have even increased by 10,000 times , it can already start to be seen in ultrasounds as a small dot swimming in the amniotic fluid.

In the 4th week of pregnancy, the outline of the main organs begins to form.

5 weeks pregnant

During this week, you might start to feel very sleepy and begin to experience mild nausea.

In addition, the alteration of hormones could start to cause mood changes that are now noticeable to others.

How the body changes in the fifth week of pregnancy

Your body will experience a significant increase in estrogen levels, this rise will be reflected both psychologically and physically.

Your breasts will start to hurt a bit more and feel heavy, as well as noticing an increase in size.

Finally, you might start to notice a mild heartburn and a sensation of heaviness in the pelvic area, this can improve by taking a warm water bath, it will surely make you feel better.

How the baby grows during week 5 of pregnancy

During this week, we will witness the development of the embryo's brain, heart, digestive system, and spinal cord.

6 weeks pregnant

Starting this week, to the previous symptoms, you will likely have to add leg heaviness and unusual salivation. If this happens, do not be alarmed, these are the most common symptoms that begin to intensify from this period.

Among them, the most common is feeling nauseous in the morning, more than half of pregnant women suffer from it in the first two months of pregnancy.

How the body changes in the sixth week of pregnancy

During this week, new discomforts might start to appear and your body can begin to round out, especially your abdomen, and the growth of the breasts is definitely noticeable.

It is a good time to start planning the appointment with your gynecologist for the first ultrasound, which should be done between week 11 and 12.

How the embryo grows during week 6 of pregnancy

During these seven days, eyes and ears will start to form and the brain begins to organize.

7 weeks pregnant

The so-called hCG hormone (human chorionic gonadotropin) could reach its highest level and significantly worsen morning sickness.

This can be a very long week, but don't worry, you will soon feel better.

You can relieve it by eating fresh fruit pieces every two hours, it is even recommended to eat something very light before getting up.

How the body changes in the seventh week of pregnancy

The first thing you will notice is an increase in heart rate, it is important that you do not stress too much or engage in heavy activities, because it is more than likely that you will get tired sooner than expected.

How the baby grows during week 7 of pregnancy

Starting this week, the embryo will measure just under 2 centimeters and weigh about 2 grams. Its heart continues to develop, as does the tissue for its bones.

To promote the formation of the bones and skeleton, it is important that you do not neglect either your diet or lifestyle. Therefore, we suggest that you contact your gynecologist for advice.

8 weeks pregnant

You are already two months pregnant, you can continue to feel nauseous, most likely it will be much milder than the previous week, however, this can be different in every woman.

How the body changes in the eighth week of pregnancy

The fetus begins to occupy a significant space in the uterus, therefore, the belly will start to visibly gain weight. Your internal organs begin to move to adapt to the new situation.

The uterus begins to weigh down on the bladder, you may feel an increased need to urinate and you will have to start doing it more often than usual.

How the fetus grows during week 8 of pregnancy

In these first weeks of pregnancy, the fetus will have grown a lot. From a handful of cells, it starts to take on more human form and that of your future baby. It now measures about 2 centimeters and its nervous system is developing.

9 weeks pregnant

This will be the first week of the third month in state, the ailments you suffered during the previous 3 months will not disappear yet, they will probably remain until week number 11.

You can start to notice weight gain, as between the first and 3rd month of pregnancy, it is estimated that you have already gained approximately one kilo, monitoring this is very important, so it is important that you keep a little chart with your weight increase, although your doctor will also monitor this.

How the body changes during week 9 of pregnancy

From this week on, the renal effort will increase a lot, therefore, it will be essential that you drink a lot of water.

The uterus is starting to grow and it is possible that others can tell you are pregnant by looking at you, and from this week a process of growth at great speeds will begin. There will already be clothes that fit tightly or that do not fit you.

How the baby grows in week 9 of pregnancy

From this week, the head will start to grow until it becomes a third of the total body. The development of arms and legs occurs. All essential organs have begun to grow, such as the liver and spleen for example.

As for the limbs, both arms and legs will continue to grow, forming the toes.

10 weeks pregnant

How great that you are already 10 weeks along! It means that your pregnancy is well on its way. The belly remains more or less the same as the previous week, but from now on it will not stop growing.

During this week, vaginal discharge may be more abundant than the last, if it has a stronger odor than before, we recommend you urgently visit your gynecologist.

How the body changes in the tenth week of pregnancy

As we have already said, the uterus, and therefore the belly, will have grown slightly compared to the previous week and you might feel some minor cramps because of this.

The breasts continue to grow and you may already need to change your bra size

How the baby grows during week 10 of pregnancy

Starting this week, the fetus begins to take on a human shape, moreover, its little ears start to form. It is already moving even though you cannot feel it yet

For its part, the liver will continue to grow, becoming much larger compared to the other organs.

There are only a couple of weeks left to have your first ultrasound, although sometimes gynecologists prefer to do it during the tenth week instead of the twelfth.

11 weeks pregnant

You are a week away from finishing the first trimester, you should start to feel better, if not this week then in the next 2 weeks. Morning sickness will begin to disappear.

How the body changes in the eleventh week of pregnancy

The belly is visibly swollen and there is a noticeable change from the previous stage. In other words, if in the previous weeks you could still hide your condition, from this point on, it will be impossible, it is too obvious that you are pregnant.

You might start to notice some changes in your hair and nails, both can grow more than usual due to the action of hormones. Your hair will look shiny and the nails will be firm.

How the baby grows during week 11 of pregnancy

The bones are in full process of formation, as is the spinal column. The head remains too large in relation to the rest of the body.

In total, the fetus will weigh around 8 grams. Its heart beats between 120 and 160 beats per minute and you can already see this on an ultrasound.

12 weeks pregnant

During this week, or by the end of it, you will have fully entered the third month of pregnancy. Morning sickness should have disappeared.

However, on the other hand, you may start to feel much more tired, take your moments of tranquility. It is very important to rest

How a woman's body changes in the twelfth week of pregnancy

The belly starts to take a much more rounded shape. You may feel weight and discomfort in the lower abdomen, but you should not feel pain, if something bothers you, more than usual, consult your doctor

How the baby grows during week 12 of pregnancy

Starting from the previous week, each week that passes the fetus will take on an increasingly human shape. Its organs are already formed.

This is often one of the most chosen weeks to perform the first ultrasound, if you haven't done it yet, we recommend that you get in touch with your gynecologist.

13 weeks pregnant

This week is considered a turning point in your pregnancy, as it marks the end of the first trimester, you can now shout loud and clear that you're going to be a mom!

Once you've passed the first trimester, it's most common to feel less tired compared to the previous weeks. You will also experience a weight gain that will further evidence that you are pregnant.

Maintain a healthy and balanced diet and you can include exercise, it will do you good

Changes in your body during the thirtieth week of pregnancy

In addition to the substantial increase in belly size, your skin is likely drier than in previous weeks. Keep the skin of your belly moisturized, do not stop taking care of it

From this week, your body is starting to change structurally, you have entered a completely different phase than before and your body must readapt.

The baby's growth in week 13 of pregnancy

For the first time during the whole process, it will open its mouth, this means it is preparing to be able to feed, it will start to drink amniotic fluid and its already developed kidneys produce urine.

At this point, the fetus measures approximately 6 centimeters, still having the head disproportionately large compared to the rest of the body.

14 weeks pregnant

You have now fully entered the fourth month of pregnancy, and therefore, the second trimester. Your baby is growing very quickly and in a very short time, you will start to feel their first movements.

During these days, you may start to notice digestive imbalances or other kinds of stomach pains.

How your body changes in the fourteenth week of pregnancy

You are in the second trimester, nausea should have improved, as well as extreme tiredness. The uterus continues to increase in size and the breasts will continue to grow.

How the baby grows during week 14 of pregnancy

In a few days, the fetus will change rapidly, beginning to be able to perform some actions, such as giving hugs or moving the lips. It might even try to suck its thumb, which you would see in an ultrasound.

Its face is already well-formed and its genitals differentiated.

Normally, at this stage of the process, the fetus usually weighs about 25 grams, however, it can measure up to 10 centimeters.

15 weeks pregnant

Throughout this week, you will feel more energy, but take it slowly. If you hadn't started exercising, it's a good time to begin, as long as your doctor allows it.

How your body changes during the fifteenth week of pregnancy

The belly will continue to grow non-stop, while nails, hair, and skin will start to shine much more brightly thanks to the hormones you exceptionally produce while being pregnant.

How the baby grows in week 15 of pregnancy

At this point, the baby begins to have transparent skin, the 4 chambers of their heart are formed, as well as their bladder, their hands can now open and close, and they might even yawn.

16 weeks pregnant

You are still in the second trimester of your pregnancy and it's good to know that it's a wonderful time to enjoy your well-being, you haven't gained a lot of weight yet and the pregnancy symptoms seem to have disappeared.

How the mother's body changes during the sixteenth week of gestation

The height of the uterus keeps growing and you might feel that sometimes your belly can get hard, that is, you might feel some contractions, don't worry, your uterus is simply training for childbirth.

However, if the contractions become frequent or too strong do not hesitate to call your gynecologist, as this is not normal.

How the baby grows during week 16 of pregnancy

Throughout this week, the fetus will make a lot of progress, reaching a weight of 70 grams and measuring 10 centimeters.

The ear holes and fingerprints will start to form. It continues its process of gradually adopting the human shape, energetically moving arms and legs

17 weeks pregnant

This week you feel so good that your appetite is increasing, but be careful, eating for two is not allowed, remember that weight control is part of managing a healthy pregnancy.

How your body changes in the seventeenth week of pregnancy

Be careful with blood circulation! Because varicose veins may start to appear. This is because the uterus increases in size and this directly affects circulation, as it puts pressure on the veins in the pelvis.

How the baby grows in week 17 of pregnancy

You might already be feeling your baby's movements, they have plenty of room to do so and move like a little fish.

The nails and hair will grow quite a bit, on the other hand, the veins can be seen through the skin which is transparent at this stage of their growth.

The digestive system will take its first steps this week. The fetus measures 11 centimeters and will already weigh about 100 grams.

18 weeks pregnant

If you are a first-time mother, you might already strongly feel the presence of the baby in your belly, which occurs between this and the 20th week.

As the days pass, the movements you feel inside your womb will change day by day until they become completely noticeable.

How your body changes during the eighteenth week of pregnancy

You might feel tired again, when you lie down try to do so on your left side from now on, this prevents your uterus from pressing on the vena cava and thus facilitates venous return.

Also, because of this pressure on the bladder, you may experience frequent urges to urinate again.

Otherwise, this will be a week quite similar to the previous one.

How the baby grows during week 18 of pregnancy

The heart is already fully formed and now beats at 120 to 160 beats per minute. Neurons begin to multiply exponentially, creating multiple connections. Its ears are now in their final position

It now measures about 14 centimeters and weighs around 200 grams.

19 weeks pregnant

You are about to enter the fifth month of your pregnancy. This may be one of the sweetest periods of the whole process. You will probably start to feel hungrier.

How your body will change during the nineteenth week of pregnancy

Your belly now reaches the height of your navel. Your nipples become darker and you may notice spots on your face, this is known as “pregnancy mask

You may also notice that a dark line can appear from your pubis to your navel.

How the baby grows during week 19 of pregnancy

From this week on, the fetus will be able to join its two hands and touch other parts of its body, yet it will spend most of the time sleeping. It measures about 15 centimeters and begins to be covered with a special fat called "sebaceous vernix" or vernix caseosa.

This fat protects it from the amniotic fluid and provides warmth. Moreover, your baby can now hear you, its cochlea in the ear has developed, this allows it to hear you, talk to it, it is happy to hear your voice and that also establishes a unique and special relationship.

Its movements are becoming more frequent, partly because it now has much more space to move around.

20 weeks pregnant

You have reached the halfway point, and a lot is happening. And very quickly! The baby is moving a lot now and making movements that you can start to feel, you have probably gained some weight compared to the previous week.

Starting this week, you should be very vigilant about monitoring your blood pressure, until now, it was probably low, which could cause dizziness, but from this point on you should be attentive to preeclampsia.

How your body will change in the twentieth week of pregnancy

You are right in the middle of your pregnancy, but your body will continue to change just the same. The uterus continues to grow, to the point that it starts to make deep breathing a bit difficult, so, this week you may start to notice some slight breathing difficulties.

The gums are more sensitive at this time and may bleed easily, it is important that you see a dentist, because it could eventually become infected.

How the baby grows during week 20 of pregnancy

The fetus's movements gain more precision every day, and its muscles strengthen allowing it to perform more difficult movements within the uterus.

Eyebrows and eyelashes appear and it is covered by a very soft hair called lanugo.

The rapid growth of the fetus during the last few weeks will start to slow down during the second half of the pregnancy. The fetus will continue to grow, but at a much slower pace.

21 weeks pregnant

You are in your fifth month of pregnancy. Many gynecologists choose this week to perform the morphological ultrasound, which is a very important exam that helps to ensure the child is growing well and does not have any malformations or anomalies.

How your body will change during the twenty-first week of pregnancy

You might suffer from a slight iron deficiency, so pay a bit of attention to what you eat, but also don't neglect your weight. Up to now, you should have gained between 4 and 6 kilos. If you exceed this figure, your doctor will probably tell you to be extra careful with your diet and the "cravings".

During this time, as well as throughout the pregnancy, you should be careful of urinary infections , which are very common in your condition and could jeopardize the normal course of the pregnancy.

How the baby grows during week 21 of pregnancy

The fetus is already very active, kicking the belly and moving continuously. Now it should weigh around 280 grams and measure 16 cm.

Its lungs are already developing, it's possible that your baby might start to experience hiccups, and that's why you might feel it jump occasionally. If you have the morphological ultrasound, if you hadn't seen it before, you will surely be able to know its sex.

22 weeks pregnant

It tends to be a rather quiet period, you shouldn't carry too many kilos, and in general, you shouldn't feel too tired. It is surely the best time to take that small, short trip you had in mind.

How your body changes during the twenty-second week of pregnancy

At the beginning of this sixth month, the belly should already be noticeably large due to the uterus reaching a high volume, it is also possible that cramps appear. Try to massage your calf before sleeping and to rest your legs during the day.

The hormones make the skin, although smooth and hydrated, can cause some pimples due to the produced grease.

How the baby grows during the 22nd week of pregnancy

The fetus will continue swimming in its pool of amniotic fluid and you will continue to notice its movements more and more.

It is really very active, but will continue to sleep almost all day, about 15 or 16 hours. It now weighs about 400 grams and meconium is forming in its intestine, which after birth, will be its first stool.

23 weeks pregnant

During this period, you might experience Braxton Hicks contractions or preparatory contractions more frequently, they are called preparatory because they are precisely preparing the uterus for when the time of childbirth comes.

They are not something to worry about, they are occasional, not painful, and should not be rhythmic. If any of this were not the case, you should go to your doctor.

How your body changes during the twenty-third week of gestation

Once again, your breasts may start to hurt, with the pain progressively increasing, as they are slowly preparing for breastfeeding.

The thyroid may show some hyperactivity, and this can lead to an increase in body temperature. Your heart beats faster than expected, and sweating will be higher than usual.

How the baby grows during week 23 of pregnancy

During this week, the baby will sleep a lot and will have less and less space to move. However, it will make between 50 and 100 movements every hour, far exceeding the movements of most previous weeks.

Its brain structure develops more and more, with half a million nerve divisions occurring every 2 minutes.

It begins to have eye movements

The fetus weighs approximately 450 grams and measures about 27 centimeters. Starting this week, the teeth begin to form.

24 weeks pregnant

You are entering the sixth month of pregnancy. The fetus continues to sleep peacefully most of the time, but when awake, it will spend most of the time kicking.

As a general rule, it is a quiet week, you shouldn't have gained too many kilos, but you will probably start to notice that your ankles swell a bit at the end of the day, as with the entire pregnancy, everything has a limit, if this edema or swelling increases you should consult your doctor.

How your body changes in the twenty-fourth week of pregnancy

Your uterus has already surpassed the navel by a few centimeters and your skin continues to stretch, so keeping it well hydrated with suitable creams is very important.

The gums may continue to swell due to the effect of hormones, which during pregnancy are produced by your endocrine system.

How the baby grows during week 24 of pregnancy

The fetus continues to swim inside the amniotic fluid, during this period you can feel its movements. It still sleeps most of the time, and is only awake for 4 hours a day, during which it will not stop moving between the upper and lower part of the abdomen.

It still keeps its eyes closed, but we can see its first smiles.

Also, the grasping reflex appears and the prints on its feet and hands are formed

Its pulmonary alveoli are already developing, which is very important for its breathing later on.

Its immune system begins to function because its body produces white blood cells.

25 weeks pregnant

You are in week 25 of pregnancy and are already at the doorstep of the third trimester. The baby will start to develop sight and you will continue to gain weight, albeit at a much slower pace.

How your body will change during the twenty-fifth week of pregnancy

The uterus continues to grow causing heartburn and gastric reflux. You might start to notice some type of small contractions more frequently than before, not especially painful, and they will not be regular either.

The weight of the uterus, which has now reached the size of a soccer ball, might start to be a bit bothersome, as it will increase your need to urinate.

Your doctor should have already indicated the glucose tolerance test, it is very important that you do it.

This is an ideal time to do some exercise and strengthen the muscles of the pelvic area.

How the fetus grows during the 25th week of pregnancy

Its skeleton will start to take shape and its face to firm up, both the neck and the nails will develop.

It continues to spend a lot of time sleeping, but it is likely that its sleeping times are different from yours, if you are lying down, it will move much more, whereas if you are moving, it will take the opportunity to sleep.

The fetus, during this week, will weigh 600 grams and be 30 centimeters long. It has started to develop sight, and now opens its eyes occasionally, although it will only see the darkness of the belly, it will serve as training.

26 weeks pregnant

On the third day of this week, you will enter the seventh month of pregnancy, and officially, you will inaugurate the third trimester of gestation.

The child growing inside you is becoming more receptive to external stimuli, and you will start to notice the weight of the child more and more.

How your body changes in the twenty-sixth week of gestation

The uterus has significantly increased in size, pushing and compressing the diaphragm and lungs (you might find yourself short of breath at times) and slightly moving some organs like the stomach.

You might suffer from some indigestion or heartburn, this is because the child is putting pressure on the stomach and you could feel full much sooner than usual.

Normally, the main cause of stomach acidity tends to be the position you adopt, as sitting for a long time compresses the belly, producing a certain abdominal pain.

To avoid all these pains, it could be useful to practice light sports and do gymnastics.

How the child grows in week 26 of pregnancy

Now he is much more receptive to external stimuli, such as sounds, therefore, he better defines sounds, you can play music for him and it will reach his ears, and influence him to relax or excite him.

He is accumulating more fat, which is part of his protection.

His lungs will continue the development process, and he is capable of primarily using the muscles of the respiratory system.

27 weeks pregnant

You have just started the seventh month of pregnancy and you are in the last trimester of your pregnancy! It's time to take stock of how your weight has grown and how your baby has been growing.

How your body changes during the twenty-seventh week of gestation

It would be good for you to start drinking large amounts of water daily, to improve drainage and relieve swelling of the legs, as well as to combat dehydration. You should be attentive to whether your hands or your face swell; if this happens, you should consult your doctor immediately.

You will notice an increase in your caloric needs, as the fetus is growing a lot and very quickly.

How the fetus grows during week 27 of pregnancy

The fetus weighs approximately 760 grams to 800 grams and measures about 35 centimeters, each day it looks more like a miniature human being. It should have reached one-third of the weight it will have at birth and during this month it will manage to double its current weight.

The connections between neurons are being completed, however, the child's movements are not yet coordinated. It already opens and closes its eyes

The taste buds will also develop, starting to distinguish the flavors of the foods that reach it through the amniotic fluid.

28 weeks pregnant

You have officially entered the third trimester of your pregnancy, the coming weeks will be somewhat more tiring, you will gain a bit more weight and the child will almost completely develop. We recommend resting as much as you can.

How your body changes during the twenty-eighth week of pregnancy

From now on, gynecological visits will increase in frequency. The doctor has probably already requested a test to see if you are RH negative.

Your back may start to hurt and you might feel tingling in your legs. Lift them up every so often, lie down and let them rest about 15 centimeters above.

As we have already said, it is most advisable to rest and relax as much as possible.

How the fetus grows in week 28 of pregnancy

Its brain keeps growing. The fetus continues to drink amniotic fluid, hears sounds and recognizes those that are more familiar to it, and it now starts to react to all kinds of stimuli. It responds to light and sound stimuli

It already has all the reflexes it will have at birth: grabbing things, sucking on them, looking at them, and moving.

Both hair and nails will continue to grow, and, if it is a boy, the testicles begin to descend from the scrotum starting from the 28th week of pregnancy.

29 weeks pregnant

You are reaching the end of the seventh month of pregnancy. The fetus is already of considerable size, and your belly is starting to become too small for it, leaving less space for movement.

It is moving considerably, and sometimes, especially if you are lying down, you will be able to feel its movements inside the belly.

How your body changes in the twenty-ninth week of pregnancy

The dimensions of the uterus continue to increase and can even reach up to the chest, your heart beats very fast and you will tire very easily, as in the previous week, pay attention to rest.

The breasts will increase in size and weight, and the veins around them will become much more evident.

How the fetus grows during week 29 of pregnancy

You have reached week number 29, and the fetus will not stop growing almost until birth. Its head starts to have a more proportional shape and size in relation to the body.

It weighs almost a kilo and measures around 38 centimeters. The maternal uterus is becoming smaller and smaller for it.

Its respiratory movements are becoming more rhythmic.

30 weeks pregnant

In this thirtieth week of pregnancy, the child might turn head down, to prepare for birth.

You are concluding the seventh month of pregnancy, and you are about to enter the eighth, and penultimate, month of gestation.

How the mother's body changes during the thirtieth week of gestation

It's important to follow a healthy and calming lifestyle, excessive fatigue or high stress can encourage contractions.

Constipation might be bothering you, eat fruits, such as papaya and oranges, increase the amount of fiber and drink water. Insomnia might also be starting to affect you.

Most likely, the doctor will prescribe the last ultrasound corresponding to the third trimester: the fetus has grown large and can now be seen in its entirety and clearly through the screen.

How the fetus grows during week 30 of pregnancy

The brain keeps developing intensely, and the fetus continues moving non-stop. In this phase, we are already in what is called moderate prematurity, surpassing the previous phase. If the baby were born at this moment, their chances of survival would be relatively high.

31 weeks pregnant

During the 31st week of pregnancy, the baby will turn many times until it is head down, which is the ideal position for birth. The uterus becomes smaller with each passing day, which means that childbirth is approaching.

How your body changes during the thirty-first week of pregnancy

Since the uterus has increased its volume tenfold, you will feel your lungs being compressed.

The weight of the child is becoming increasingly difficult to carry, and your spine and bones may start to suffer. You could have more frequent back pain, caused by poor posture and an unorthodox curvature of the spine.

To prevent back pain, we recommend doing some exercises that can mitigate it.

How the baby grows during week 31 of pregnancy

The fetus will have both legs and arms crossed, looking for the correct position for birth. This position consists of bent knees, crossed arms and legs, and resting the head on the chest.

Its bones continue to strengthen, and therefore, it is essential that you consume foods containing calcium.

The baby accumulates fat, which means its skin starts to be less wrinkly, and also accumulates calcium, iron, and phosphorus.

32 weeks pregnant

Starting this week, the child will gradually begin to take on the typical traits of a baby. Between this week and the previous two, one of the last ultrasounds of the entire process should have been carried out, which aims to confirm the child's growth.

The fetus is practically formed, however, if it were born now, it would need an incubator to survive.

How your body changes during the thirty-second week of pregnancy

You may still be gaining weight, it's possible that some colostrum is already coming out of your breasts, as a sign of preparing for breastfeeding,

On the other hand, you might start to feel a strong retention of fluids in your legs and even hands, this should be monitored by you and your doctor.

How the fetus grows during week 32 of pregnancy

The fetus's skin is still coated, but it is becoming more human-looking and smoother. The baby measures about 40 centimeters and weighs around 1.5 kilos.

The growth of the nails has not stopped yet. It begins to distinguish between darkness and light.

33 weeks pregnant

Pregnancy is about to enter its final phase and you might feel tired, hang in there, you are reaching the end of the process.

How the fetus grows in week 33 of pregnancy

During the eighth month of pregnancy, the fetus is practically the same as a baby. Its brain evolves rapidly, as does its immune system.

The only thing left to develop is its respiratory system, which is why babies born this week often need an incubator to survive.

It drinks a lot of amniotic fluid, and, because of this, urinates many times. It is already capable of recognizing the flavors of food, so, we recommend paying a little attention to what you eat.

34 weeks pregnant

You are in week 34 (eighth month) of your pregnancy, which is relatively close to its conclusion.

You are about to enter the last phase of your pregnancy and soon you will be able to embrace your child.

How your body changes during the thirty-fourth week of pregnancy

Maintain an adequate intake of fruits and vegetables, watch that your ankles do not swell excessively

The breasts are getting larger, you feel that the hips have widened, which occurs because the joints are adapting for the baby's passage through the birth canal, and the cervix will be somewhat softer because it is preparing to give birth.

If you feel contractions, watch that they are not regular, if so, urgently see your doctor.

How the fetus grows during the 34th week of pregnancy

All its organs are practically developed, including its lungs. It should weigh almost 2 kilos and measure about 42 centimeters.

The hair begins to develop strongly,

During the 34th week, the child does not have too much space to move, mainly due to its size increase, but still manages to perform a whole series of small movements.

35 weeks pregnant

During the 35th week, you are finishing your 8th month, but by having 35 weeks and 3 days, you will already enter the ninth month of your gestation.

How your body changes during the thirty-fifth week of gestation

The ligaments and muscles begin to relax to prepare for childbirth, and this could cause pain and fatigue in your hips.

Sometimes the pain can even be felt in the buttocks and legs.

You might also notice some acidity in the stomach due to gastric reflux. Eat more often, but in smaller amounts, choose low-acid foods, and avoid fats.

How the fetus grows during week 35 of pregnancy

The fetus already exceeds two kilos and measures approximately 45 centimeters, most of its organs have reached a high degree of formation and it is capable of breathing, eating, and even digesting on its own.

It always tries to move a lot, but the space it still has is minimal and it would not be surprising if you start to notice its little kicks very intensely and easily get a hinted little foot on your belly

36 weeks pregnant

Starting from this 36th week, it would be rather appropriate to undergo a weekly check-up. If possible, during these weeks we recommend you visit a delivery room in the hospital where you plan to give birth, because, in reality, you are already in the ninth month of pregnancy, and you will give birth very soon. Try to have your things and the baby's ready in case you have to go to the delivery room earlier than expected.

How your body changes in the thirty-sixth week of pregnancy

The uterus is already preparing for childbirth, and it is not surprising that during this week you may start to feel contractions more frequently, only they are not yet regular and constant, these are symptoms that generally should not last more than 30 seconds.

From now on, you will start to gain, more or less, about 250 grams a week. On average, the total weight gain during pregnancy, once this week is reached, should be approximately 10 kilos.

How the fetus grows during week 36 of pregnancy

The weight that the fetus reaches this week, should already be the same that it will have at birth, it is just a matter of time before it happens.

From this week, the baby takes on the shape of a child surpassing 2.3 kilos and reaching more than 45 centimeters in length.

The lanugo begins to disappear now.

If born at this time, it is still a premature baby, as indicated by the WHO, however, its lungs are developed and it can breathe on its own

37 weeks pregnant

You are almost at the end of the journey, it won't be long before you have your baby in your arms. There is not enough space in your belly, and the fetus has become too large and cannot move as much as it would like, but it still keeps moving, and it is very important to be attentive to this, a reason to urgently see your doctor is if you notice that suddenly your baby stopped moving.

Already this week your baby can be born at any moment

You may feel more tired than usual, and start to feel a bit of anxiety and fear about childbirth, stay calm and relax.

How your body changes in the thirty-seventh week of pregnancy

The hormonal changes that will take place from this week until just before birth will cause you some fatigue.

On the other hand, you might start to notice your belly harder than usual due to contractions, a phenomenon that occurs with different intensity during the nine months of pregnancy.

You feel that your belly has dropped a bit, as the baby is already in position and perhaps about to engage to be ready in the birth canal shortly, that will make you walk differently.

How the fetus grows during week 37 of pregnancy

The fetus has already exceeded 2.5 kilos in weight and 45 centimeters. The lack of space will make its movements difficult, but if you feel that it does not move at all, quickly get in the hands of a specialist to see what happens.

The baby continues to prepare to not have respiratory problems and has probably already done some small rehearsals. It already has defined sleep patterns

38 weeks pregnant

In this 38th week, the child will fully complete their development and growth, doctors usually pre-register the due date for week 40 from the last menstruation, but in reality, the fetus's formation has already ended during week 38.

How your body will change during the twenty-second week of pregnancy

The joints relax due to the weight of the baby and the belly, therefore, you may feel some slight contractions, as in the previous weeks, if the contractions were regular do not hesitate to call the doctor.

How the fetus grows during the 38th week of pregnancy

Its dimensions are approximately 48 centimeters and 2.8 kilograms in weight. The reflexes are already coordinated.

Its immune system begins to produce its first white blood cells and its liver is already functioning normally, gaining approximately 30 g in weight each passing day.

39 weeks pregnant

If you have reached this week, you are about to conclude the ninth month, this is very likely your last week of gestation.

In fact, most women start to feel contractions these days, and most children are born during this week. It is possible that at any moment your water will break.

How your body changes during the thirty-ninth week of gestation

Your body is preparing for the big day when you will give birth to your son or daughter. The cervix begins to dilate and becomes softer, and your belly has already reached its maximum size.

Among the changes you might notice, the most notable of all is the shift of your center of gravity along with the feeling of heaviness and volume.

Your breasts will now be noticeably larger and more sensitive, as they are preparing for breastfeeding. You will likely have trouble sleeping at night and will need to go to the bathroom more frequently.

How the baby grows during week 39 of pregnancy

This week is usually the time when the baby will be born, so their organs are already ready and will be able to survive in the outside world.

They have increased their size by eight in the last 3 months, and their weight by up to 600 times.

Their fingernails have grown, they might even need to be trimmed at birth so they do not scratch their face.

Their intestines will be full of meconium, which is produced by the ingestion of amniotic fluid, lanugo, a mixture of bile, among other substances.

40 weeks pregnant

You have already reached the end of your journey, very soon you will have your child in your arms. This week will mark the end of the ninth month of gestation. This long journey of 40 should conclude here, if not, consult with your specialist about the reasons.

How your body changes during the fortieth week of gestation

Pay attention to any contractions, when they start to become regular and you lose fluids, go quickly to the hospital with your bag packed, for both you and your child.

Keep in mind that you could give birth at any moment, so take your time, relax, sleep, and don't stress too much, the action will soon begin.

How the baby grows during week 40 of pregnancy

During this week the baby has already reached its maximum growth point. On average they tend to measure around 48 to 50 centimeters and weigh about 3 kilos.

The baby is more than ready to leave its warm habitat and launch into the arms of life to arrive at a place it has not yet known, prepare to welcome it with all your love.

And that concludes our review of all the weeks of gestation, where you have learned about the changes that will occur during the 40 weeks both in your body and in the growth of the child.

Bibliographic References

  • Guindel M. You're going to be a dad. Madrid: Difusora Larousse - Ediciones Pirámide; 2014.
  • Fetal development [Internet]. 2017. Available at:
  • Langman J, Sadler T, Bridges T, Leland J, Sadler-Redmond S, Tosney K et al. Medical Embryology. Buenos Aires: Editorial Médica Panamericana; 2009.
  • Wikipedia Contributors. Prenatal development [Internet]. Wikipedia, The Free Encyclopedia; 2018. Available at:
  • Third trimester pregnancy [Internet]. EGOM - Gynecology and Obstetrics. Available at:
  • Preterm births [Internet]. WHO. Available at:
  • Let the baby determine the due date [Internet]. OCPL NIH. 2013. Available:
MD Katiuska Ríos Calderón
Doctor of Medicine and Surgery from UCLA. Specialized in Gynecology and Reproduction. Subspecialized in Endocrine Gynecology and Climacteric.
Dr. Katiuska Ríos Calderón holds a degree in Medicine from the Universidad Centr... Read more »

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