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Here you will find our information on pregnancy listed by week



First Trimester

Second Trimester

Third Trimester

Also please see our information regarding fathers & pregnancy in our fathers section



Congratulations on your new family member! This will be the greatest adventure of your life. They saying having a baby changes everything, well they are right. Your body as well as your mind will change and grow with your baby. Pregnancy can bring a rollercoaster of emotions, thoughts, questions, and much more. Here you will be provided with a week by week walkthrough of your pregnancy. Included will be what is happening with your baby at that point, what you may be feeling and tips to help keep you and your baby healthy. Please remember when reading that every pregnancy is different. All women will develop at different rates and if you have already had a baby you may notice that this pregnancy is nothing like the other/s were. Also the information here is for single births, not twins, triplets, etc. ALL information is approximate, and is NOT intended to be used as the only means of health care for you and your baby. You should always take your doctors word over anyone else’s. It is best to find a doctor you feel comfortable with and can keep as your health care provider for your entire pregnancy. Every doctor will have a different opinion about your pregnancy. Each doctor measures differently, and will have different opinions on diet, and on every other angle of your pregnancy.
One doctor will say your trimesters are- 1-14 weeks for your first trimester, 15-27 for the second, and the last weeks is your third. (Others will say 1-12, 13-24, and 25-40 for the third.)  

Please email any questions or comments you may have about our pregnancy section. Your comments help to better our site to bring you the best information we can.

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fetal growth chart

First Trimester: 1-12 weeks 

Week 1:
fetus 1 weekConception hasn’t actually occurred yet. Week one begins with the start of your menstrual period. For women with a 28 day cycle, ovulation occurs around 14 days after the start of your menstrual cycle. Now is a good time to begin healthy habits (if you haven't yet!). Start eating healthy food such as fresh fruits and vegetables; exercise; start taking additional folic acid if you haven't already;
Don’t smoke, drinking alcohol, or use over-the-counter medications. Stay away from toxic materials and rest well. If you start thinking like your pregnant before you conceive you can give your baby the best start possible.


Week 2:
Now your uterus has shed its lining (your period) and is now preparing the blood-rich tissue to hold a growing fetus. Your ovaries are preparing to release one of your eggs. Twins, triplets, etc. occurs when your ovaries release two (in case of twins) or more eggs.


Week 3:
fetus 3 weeksNow is when the sperm and eggs join in the fallopian tube and the miracle of life really begins. Although several sperm may penetrate the egg's outer layer, only one sperm will enter the ovum and fertilize it. In the middle of the ovum, the chromosomes of mother and father combine and bits of information from both the mother and father begin to form the chromosomes of your baby. Did you know that from the moment of conception your baby’s gender is determined by the sex chromosomes held within the father’s sperm? This time, it’s okay to blame it on dad! At this time you may experience some spotting or bleeding. Don’t worry this is completely normal, some women experience this and some don’t). Most women don’t really know the exact moment of conception.


Week 4:
Implantation is occurring. Implantation is when the blast egg burrows itself into the lining of the uterus.  Once the egg gets to the uterus is finds a spot to latch on to. Once it finds a place the cells begin to divide to make the placenta and your baby.


Week 5:
fetus 5 weeksNow is when your period should be starting. It hasn’t? You feel moody, breast soreness, you’re tired a lot? “Could I be pregnant?” is what usually goes through your mind about this time. You have taken that pregnancy test and just found out that you are pregnant. Get ready; your body will go through hormonal changes. You may feel hungry all the time, or nauseated, your breast will grow as your body produces more milk glands in preparation for baby, and you may find that you have to sneak off to the bathroom several times as your uterus begins to press on your bladder. You should find a health care provider, as soon as you find out you are pregnant.

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Week 6:
fetus 6 weeksYour baby is called an embryo and about 1/17 of an inch long. There is much that happens this week. Its eyes and ears begin to form and open. The umbilical cord forms. Your baby’s heart can pump blood and (heartbeat), and most of the other organs are developing.  A heart beat can be seen as early as 5-6 weeks during an ultrasound examination. This is usually when morning sickness, (all day sickness!) starts to begin or gets worse. You may find that certain smells will make you sick. You may have cravings for certain foods. This is a very critical time in development for your baby. Do not drink alcohol; take over the counter drugs or illegal drugs. NO perms, manicures, etc.


Week 7:
This week your baby is about 1/3 of an inch long. The arms and legs are continuing to develop (no fingers or toes yet). Their brain, along with the lenses of their eyes, nostrils, all the intestines, pancreas, and bronchi are all continuing to grow. This week won’t be much different from last. You may have gained a few pounds or even lost a few. But you won’t be showing yet.


Week 8: Your baby’s toes hands and feet begin to develop tiny notches for the fingers and toes. Teeth are developing under the gums; the intestines are forming in the umbilical cord, and the face changes as the eyes, ears, and nose start to appear.
Your uterus is about the size of an orange. You may notice that your pants are fitting a little tighter. You may not be showing yet if this is your first pregnancy. If this is not your first your muscles and ligaments are not so tight, and may have a little pooch already. 


Week 9:
fetus 9 weeksYour baby’s fingers appeared but they are short and webbed. The intestines make their way out of the umbilical cord and into the baby’s abdomen as the body grows. The tongue begins to develop, and cartilage and bones begin to form. You may have noticed that your breasts are getting bigger and are tender and your waistline may be growing. As your body get used to pregnancy hormones you may experience heartburn/indigestion. Many women go through a change in their desires during the first trimester. You may have morning sickness so much that you feel you can’t get out of bed. Or you may even notice an increase or decrease in your sexual desires. Either way, this is normal. Remember that your moods will be much like a rollercoaster. Talk to your partner or anyone for support and tell them what you need from them. Weather its just to listen to bring you to your appointments.


Week 10:
Even though you can’t feel it yet your baby has begun to move. The hands, fingers, feet, toes, elbow, wrist, knee, shoulder, and ankle are formed now. You may notice that you’re more moody and that your skin is blotchier, this is the hormones. You should discuss with your doctor a healthy diet. Remember to eat healthy and that what you eat your baby eats. The healthier the food is the more nutrition baby will get. Do NOT diet during pregnancy. You are NOT fat you are pregnant.

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fetus 11 weeksWeek 11:
Your baby is officially a fetus! The most critical part of the baby’s development is over. Your baby is about 1inch and growing fast, and should gain another inch by the end of this week. The eyelids will fuse shut, and the irises will begin to develop. Blood will begin to circulate between the baby, uterus and the placenta. The baby’s head is about half its length.
Your uterus is about the size of a small grapefruit. You may start to notice that your “morning sickness” is starting to ease and that you can even tolerate certain smells again. 


Week 12:
Almost all of your baby’s organs and structures are formed. Fingers and toes have separated and hair and nails begin to grow. Amniotic fluid begins to accumulate as the baby’s kidneys begin to produce and excrete urine. The genital begin to take on their gender characteristics. The muscles in the intestinal walls begin to contract with in the intestines that digest food to practice peristalsis. The increased blood volume may give you headaches and make you light headedness and it may be time to start wearing loose fitting cloths. This is about the week your uterus will shift forward and up as it grows. On a good note, morning sickness usually gets better about this time, and you may feel less tired. Baby is about 0.3-0.5 ounces (8-14g) and is almost 2.5 inches (61mm)

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Second Trimester 13-27


fetus 13 weeksWeek 13:
You are now in your second trimester! Now is when most expecting parents take a breath of relief. Your morning sickness shouldn’t be all that bothersome and you should have more energy. Most women say that this is the most “comfortable” time of the pregnancy. Your baby about 2.6-3.1 inches (65 to 78 cc) and weighs between 0.5-.07 ounces (13-20g).Your placenta has developed. The placenta is how your baby gets, nutrients, oxygen, as well as disposal of waste, produces progesterone and estrogen. Both of witch help to maintain pregnancy. Your baby is starting to look more and more human now. The eyes begin to move closer together. The intestines move farther into the baby’s body. The pancreas begins to produce insulin and the liver begins to secrete bile. Your abdomen may have some tenderness as the ligaments holding up your uterus stretch as your uterus grow. This is known as, “round ligament pain”. Nothing to worry about. If you have a concern, talk to your health care provider.


Week 14:
This week your baby will begins practicing the inhaling and exhaling movements. Form this point the baby recessives all the nourishment from the placenta. Your baby is about 3.2-4.1 inches (80-93mm) and weighs just about 1 ounce (25g). The neck keeps getting longer so the chin is no longer resting on the chest. It is getting a little easier to determine if you are having a boy or a girl, but don’t get discouraged if your doctor is unable to tell you the sex of your baby. Baby is beginning to learn to how to move his hands, but note this could be flexing more than anything. You may be experiencing some constipation since your hormones have relaxed your bowel muscles causing them to work slower and less efficiently. Your uterus is also pressing on your bowel. Be sure to increase the fiber in your diet if constipation becomes a problem. You may notice the veins on your chest and breasts are dilated and more noticeable. The areolas of your breasts may be darkening and growing in diameter.


Week 15:     
fetus 15 weeksAt week 15 your baby’s skin is very thin. Blood vessels can be seen through the skin at this point. Fine hair (lanugo hair) covers the baby’s body. The eyes are still moving inward. Your baby’s bones have already formed and are still continuing to get stronger. An X-ray (witch is not recommended) would show the baby’s skeleton.  Baby is about 4.1-4.5 inches (93-103 mm) and weighs about 1.75 ounces (50g). This is about the size of a softball. It still may not be noticeable to others that you are pregnant unless you wear maternity cloths or a swimsuit.

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fetus 16 weeksWeek16:
If this is not your first pregnancy you may start to feel the baby move at this time. If you are overweight, have a thick uterus, or this is your first pregnancy, you may not be able to feel her movement. You may notice your nose is more stuffy or bloody. This is from the increase of blood volume witch effects the estrogen levels. This makes your nasal membranes swell. Your baby is about 4.3-4.6 inches (108-116mm) long and is about 2.8 ounces (80g).  The umbilical cord has moved lower down on your baby than before. Fingernails would have grown in by now. And his arms and legs are getting longer.


Week 17:
Fat (adipose tissue) will begin to form under your baby’s skin. This fat is important to the body’s production of heat and metabolism. The average weight gain, for the mother, at this period of time in your pregnancy is 5-10 pounds. You probably have an obvious pooch. He should be about 4.4-4.8 inches (11-12 cm), and weigh about 3.5 ounces (100g). This is about the size of your hand spread wide open. You may be able to feel the baby move at this point. You may not feel baby move everyday. You will notice stronger more frequent movements as you get farther along. Some women have described it as a fluttering. Baby can suck, swallow and blink.


fetus 18 weeksWeek 18:
You should have gained about 10-13 pounds by this time. Your baby’s development will slow down a little. Baby is about .5-5.6 inches (12.5-14cm) and 5.25 ounces (150g) (half a pound). Pads are forming on his fingertips and toes. If you are having a boy his prostate gland is beginning to develop. You may notice your back starting to hurt. Or it may have started a while ago. The growth of your uterus moves you’re your center of gravity forward. If you have to use the bathroom, do it. If you hold it, it can lead to infections.  It is common for pregnant women to feel dizzy or lightheaded. The ultrasound may or may not tell you the sex of the baby at this time. Some babies seem to want to keep their sex a secret!


Week 19:
You may have noticed a big change in your skin. You may be breaking out all the time, or you may dry and flaky, or even both. Try to drink lots of water and try to eat healthy, this should help with dryness. This week baby should weigh around 7ounces (200g) and be about 5.2-6 (13-15 cm). It should be obvious by now that you are pregnant. And you may even need to buy bigger bras. It is a safe bet to say you have felt the baby move. If your skin is itchy, try a shower followed by lotion.  Don’t keep wearing rings and watches that fit tightly.


fetus 20 weeksWeek 20:
This is the half way point of your pregnancy. The baby’s will start to get a white pasty substance called vernix. This protects your baby’s skin from the amniotic fluid. You may have an increase of vaginal discharge. This discharge is usually yellow or white and fairly thick. Don’t worry this is normal. It is not known for sure, but it is thought to be caused by the increase of blood flow. Note, if you have yellow or green discharge that has a foul odor, with irritation around or in the vagina, this could be a possible infection. Talk to your health care provider.
Baby weighs about 9ounces (260g) and about 5.6-6.4 inches (14-16cm) long. You probably feel him move pretty often.

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Week 21:
It will be pretty hard to hide the fact that you are pregnant by now. Your baby is about 7.2 inches (18cm) long and weighs about 10.5 ounces (300g). You should have gained about 10-14 pounds. At this time development will slow but all the different organs are continuing to develop. It’s a good idea to exercise but don’t over do it. Your feet will swell (mostly later in the day), relax with your feet elevated. The feeling of clumsiness will continue to get worse as your center of gravity changes. 


Week 22:
fetus 22 weeksEnjoy this time. This is, most likely, the most comfortable you will be. You are not so big yet that your belly gets in your way yet. Walking isn’t too much of an effort. All in all it should be fun and enjoyable being pregnant right now.  Baby’s eyelids and even the eyebrows are developed. She is about 7.6 inches (19cm) long and weighs about 12.25 ounces (350g). Don’t be surprised if you get hemorrhoids some time during pregnancy. This is totally normal. Make sure to get the proper amount of fiber and fluids. If you have legs cramps try talking to your doctor about taking calcium. If you find that your legs are cramping straighten your legs and flex your ankles. If possible have someone massage the muscle.


Week 23:
You should have gained between 12-15 pounds by now. Baby is about 1 pound (455g) and about 8 inches (20cm) long. If you could see the baby, you would see him getting fatter, and the baby looks a lot like how it will at birth. The bones of the middle ear begin to harden as the baby is becoming better proportioned. By now you may even see when your baby moves. There is still plenty of room for baby to give you kicks, turns, stretches, jabs, and punches. You may find that your mood swings are worsening. You may be happy one moment and curled up with a box of tissue the next. Try not to worry too much. This is absolutely normal in pregnant women and is believed to be linked the changing hormones. Try to avoid salty foods. Sodium leads to swelling because your body wants to retain water.


Week 24:
fetus 24 weeksHeartburn is also part of being pregnant. Talk to your health care provider for the best thing for getting rid of it. Your baby doesn’t have as much room as he did last week but as long as there is a sufficient amount of amniotic fluid she should gain normal amount of weight. If there is not enough amniotic fluid there will be obvious decrease in the amount of weight your baby gains. Your baby should weigh about 1.2 pounds (540g) and is about 8.4 inches (21cm). Be prepared to gain a significant amount of weight this week.


Week 25:
If your baby was to be born at this point, he would have to spend several months in N.I.CU. (Neonatal Intensive Care Unit), but would have a chance for survival.  The baby is only about 1.5(700g) and only 8.8 inches (22cm) long. There are several complications that could occur if your baby was to be born now. The baby’s spine and ligaments are beginning to form, along with the blood vessels of the lungs. Also her nostrils are starting to open.

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Week 26:
fetus 26 weeks16-22 pounds should be about the amount of weight gained so far. Baby is about 2 pounds (910g) and around 9.2 inches (23cm) tall. As your baby grows back pain, legs cramps and headaches often occur more frequently. When this happens try to relax, take a bath, etc., if it is to bothersome talk to your doctor. Try lying on your left side when you rest to provide the best circulation to your baby, and you may also notice less welling when you lay on your left side. Her air sacks in her lungs are starting. The lungs begin to secrete surfactant which covers the inner lining of the air sacs which then allows the lungs to expand normally during breathing. Besides the active lung growth, the brain kicks in with brain wave activity for the visual and auditory systems.


Week 27:
This week is the end of your second trimester. Your 2/3 the way there!!
The retina (part of the eye where light images come into focus) should be developed by now and baby should begin to open her eyes.  If you experience shortness of breath, this is normal. This is because your uterus is close to your rib cage now and your lungs may not have as much room to expand all the way. The hormones help your circulatory system work more efficiently and this in turn provides baby with all the oxygen he needs, so don’t worry! Baby should be about 15.3 inches (34cm) tall and weigh about 2 pounds (1000g). If you haven’t already, you should think about scheduling parenting classes.

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Third Trimester 28-40

Week 28:
fetus 28 weeksThis is the start of your third trimester! Your baby’s brain is developing ridges on it and builds tissue. Your baby will continue to gain body fat. Your baby weighs about 2.4 pounds (1100g.) and is about 15.75 inches long (35cm). The doctor may tell you what way your baby is lying; sideways, feet first (breech), or head first. Whichever position your baby is in, don’t worry. You still have 2 months and the baby usually changes position on her own. You should have gained between 17-24 pounds.


Week 29:
Throughout your pregnancy your doctors has conducted many tests and measured all along the way. Your baby has grown and developed so much between week 1 and now. Your baby should weigh about 2.7 pounds (1250g) and be about 16.7 inches (37cm) long. You should have gained at least 19-25 pounds by this time. Those little flutters have turned into breath taking jabs and punches (if they haven’t already). Most women are told it is okay to have sex during your pregnancy. Don’t worry about hurting the baby it has plenty of cushions and will enjoy the movement. You cannot hurt your baby. Later in the pregnancy, talk to your doctor if it is still safe. 


Week 30:
fetus 30 weeksAt week 30 your baby should weigh about 3 pounds (1360g) and about 17 inches (38cm) long. Baby’s fat production continues and will help to provide warmth after birth. If you have rhythmic twitches in uterus your baby may have hiccups due to him practicing breathing by repeatedly moving his diaphragm. You may start to notice that your morning sickness returns during your third trimester. Most doctors will say it is okay to take baths. Make sure the water is no hotter than 120 degrees, and that you do not slip. Good posture can help relieve lower back pain.

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Week 31:
This is when sleeping on your side will pay off the most. You may retain water when you don’t sleep on your side. Try using extra pillows under your knees and abdomen when you sleep. Don’t wear tight fitting shoes. You may notice you need bigger shoes, especially towards the end of your pregnancy. Baby should weigh about 3.5 pounds (1600g) and be about 18 inches long (40cm). You should have gained about 21-27 pounds at this time.


Week 32:
You doctor will want to begin seeing you more often (usually every 1-2 weeks) at this point. Your calorie, protein, minerals, and vitamin intake increases so make sure to eat about 300 calories a day. Don’t forget to take your prenatal vitamins. You will have to make several trips to the bathroom everyday/night. Baby should weigh about 4 pounds (1800g) and be about 18.9 inches long (42cm). By this time your baby has use of all five senses and the last little details are just about developed.


fetus 33 weeksWeek 33:
At this point in your pregnancy the amniotic fluid at the highest level in your pregnancy. The amount will remain the same until delivery. Your baby’s brain has increased in size and is now approximately 3/8 inches in circumference. Your baby’s skin is turning from a red to a pink color. You can expect to gain a pound a week. If you experience severe headaches, sudden increase in swelling over 2-3 days, abdominal pain, or you see spots you should contact your health care provider. Baby is about 4.4 pounds (2000g) and should about 19.4 inches tall (43cm). Do not diet during pregnancy, you and your baby need all the nutrition you can get. Your baby will sleep most of the time, and can experience REM sleep. This is the state in which dreams happen.


Week 34:
Wow this week your baby weighs about 5 pounds (2275g), and is about 19.8 inches long (44cm). It is normal fear labor. The miracles of science have brought us a long way. Talk to your doctor about all your options and any questions you may have. You may not feel like eating so much anymore due to your stomach being pushed on. And your emotional changes may be very apparent at this point. Talk to your doctor about what hospital you will be delivering at what their policies are.


Week 35:
Your almost there! You may be feeling huge and tired and ready for baby come out. But, try to be patient. Maternity bras are designed to provide extra support for your growing body. Your health care provider may begin checking your cervix regularly for signs of effacement and dilation, to see what position your baby is in. Baby is about 5.5 pounds (2550g) and is about 20.25 inches long (45cm). You should have gained at least 24-29 pounds (10.8-13kg) by now. You may have a sensitive bellybutton, try covering it with a strip of paper, tape or a bandage.

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Week 36:
fetus 36 weeksYou may have gained around 25-30 pounds (11.25-12.5kg). The baby will weigh about 6 pounds (2750g) at this point. He is about 20.7 inches (46cm) long. Even though you still have a few weeks, it is a wise thing to have your hospital bag packed at this point and ready to go. Don’t forget to have your insurance card and other important details in order. Think about weather you want to try a vaginal birth or cesarean, are you going to want an epidural?


Week 37:
You are now considered full term! Even though your due date is still a few weeks away, the baby can safely be born at any time now. Your appetite may return. You may feel Braxton Hicks contractions. These will be irregular and have no pattern, and usually only last a short while. Your doctor will tell you if your baby has turned to face head first or not. If he didn’t you may have to have a cesarean section. Baby will weigh about 6.5 pounds (2950g) and is about 21inches long (47cm).


Week 38:
This week baby will be about 6.8 pounds (3100g) in weight and should be about 21 inches (47cm) You may continue to get bigger but the weight gain usually slows down during the last weeks of pregnancy.  The baby can gain about an ounce every day! Take extra care you do not fall. Your center of gravity has changed and will make you fall easier.


Week 39:
Baby is about 7 pounds (3250g) and about 21.5 inches long (48 cm)
At this point all organ systems are developed and in place, including his lungs. Any time now! Remember that your pregnancy plan may not go exactly how you planned.


Week 40:
fetus 40 weeksThe baby should be about 7.5-8 pounds and be about 21.5 inches long. Did you know that only 5% of women give birth on their due date? You are only considered overdue once you are past the 42 week mark. Hold in there if you haven’t already you will be there soon. If you pass your 42 weeks your doctor will most likely want to induce you. Some doctors say that sex in the later part of your pregnancy can help cause you to go into labor.

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last updated 07/16/09