Pregnancy & Birth
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Your First Trimester
Your first trimester lasts from week 1 through week 12. Your pregnancy begins at conception even though your "due date" is calculated based on when you last got your period.
Your body may not seem to change much during this first trimester, but it is changing rapidly. Your baby is going through the most rapid period of growth he or she will ever go through.
Use this time to develop a great pregnancy diet. Drink lots of water too. "Grazing" is often the easiest way to eat plenty of nutritious foods while keeping ahead of morning sickness.
You'll also want to decide on a care provider. The pregnancy pages have information on each kind of care provider. You may only see your care provider once or twice this trimester, so good self-care is essential.
Choose wisely what you eat and what you do during your first trimester. Pick natural products and fresh food whenever possible.
The dating of your pregnancy can be confusing. Since your last period is pretty easy to mark on the calendar, your care provider will use that as the start of your pregnancy. In reality your baby was probably conceived about two weeks after your last period.
I'm going to start the pregnancy week by week calendar when you are two weeks pregnant and your baby is just being conceived.
First Trimester: Weeks 2 & 3
Conception
Your baby was conceived when your partner's sperm met your egg. Only one sperm can enter the egg. The sperm will burrow down into the inner part of the egg, and all other sperm will be sealed out.
The sperm head will swell into a nucleus within the egg, and the egg will form its own nucleus. Each of these has 23 chromosomes which will be joined together to form your baby's genetic makeup.
The nuclei move closer together until they join and become one nucleus containing all of the information that is needed for your baby to begin.
Fertilization usually occurs in the fallopian tubes. The fertilized egg, called a zygote, migrates from the fallopian tube to the uterus.
The cells begin dividing even before your newly conceived baby makes it to the uterus. Once it has arrived, it burrows into the lining of the uterus - this is called implantation.
Your embryo will leave its protective shell behind when it burrows into the uterine lining. The cells for baby and placenta have already separated.
Your tiny ball of cells is going to form into a more and more human shape rapidly, but for now, your baby is very small. In fact, your baby is smaller than a period on this page.
The cells that make up your baby are going to continue to divide rapidly over the coming week. If you'd like to follow your baby's development pick up A Child is Born
- it's an excellent and fascinating book.
You may notice some light implantation spotting, but you probably won't know that you are pregnant yet. Some women have some pain around ovulation time, which can be an indicator that pregnancy is possible.
You could have noticed that your cervical mucous changed to a fertile mucous, which is the consistency of egg whites. This doesn't indicate pregnancy, but it does show that you are fertile and that it is possible for you to have conceived.
You should stop smoking, drinking or doing any illegal drugs. There are differing medical opinions on what is safe and what is not safe during pregnancy. The very best bet is probably just to stop everything.
If you need help to stop get it now, in the first trimester. Avoid prescription drugs as well, if you can. Have a healthy, natural pregnancy and avoid any unnatural or potentially harmful substances.
Some women realize that something is going on right from the beginning! It's an intuition that they have - if you have this feeling, it will serve you well throughout pregnancy, birth, and motherhood.
First Trimester: Week 4
2 Weeks After Conception
As your baby completes implantation, he or she is officially called an embryo! The amniotic sac begins to form, and a yolk sac that nourishes your baby early in your pregnancy also begins forming.
Your baby starts to take on a more formed shape, looking somewhat like a tadpole. Your baby is entering periods of vital development and you will want to avoid exposure to anything that might hurt your baby.
This rapid growth will continue throughout the first trimester. Choose natural bath and body products and try and use natural products around the house. Limit your exposure to pollution or second-hand smoke. Also try to avoid paint fumes and fertilizers.
Your baby's placenta is also starting to develop from the cells that separated from your baby last week. Your baby's placenta is an amazing, life giving organ. Your blood supply and your baby's are separated by a thin membrane of the placenta and all the nutrients he or she needs will pass through it.
Waste products will pass from baby's side to your side and your body will deal with them. Remember that many things can pass right through the placenta to your baby, so choose wisely what you put into your body.
Hormones are being secreted that tell your body that the baby is present. Your body halts any ovulation preparations and begins to build the lining of the uterus. These hormones also protect the baby from being rejected by your baby.
You may have some more light implantation spotting, and at the end of this week you could start feeling mild nausea or fatigue. Some women also report having a metallic taste in their mouth and their breasts become tender. If you've been charting your temperature, you'll be watching to see if your temperature drops or not (if it's high for 20 days, you're most likely pregnant!)
By the end of this week you may realize that your period is late. A home pregnancy test can confirm this. You may also call your doctor or midwife to confirm your pregnancy. Many care providers will not see you so early in pregnancy. Rest assured that your attention to your diet and your own self-care help keep your baby happy and healthy during the first trimester. You may go into the office for a prenatal workup, which is a series of blood tests to assess your health at the beginning of pregnancy.
First Trimester: Week 5
3 Weeks After Conception
The baby has a head and a tail end with the forerunner of the brain and spinal cord developing. The chorionic villi, or the tissue that line the placenta have finished forming. If you opt for a CVS test, then these are the tissues that will be used for the sample. The villi grow so that they end up dipped in "lakes" of your blood, though your blood and your baby's never actually mix.
This is how nutrients will be transferred from your blood to your baby's. Late this week your baby will enter a critical period for heart development.
You will probably have missed your period this week and will begin suspecting pregnancy if you haven't already. Take a home pregnancy test or call your doctor or midwife. Your breasts may feel sore or tender - it is often a first sign of pregnancy. Fatigue and queasiness may continue or begin this week.
Some experts believe that your nausea may be caused by the placenta purposefully. You might find that things with strong tastes and smells cause you to feel ill, and that you avoid them. This could be how your baby's placenta ensures that nothing harmful is going to get to your baby - especially during the sensitive first trimester.
The hormones being produced by your body and the placenta cause an aversion to things with heavy odor or taste - things that might also be likely to harm your baby. As you will continue to learn throughout pregnancy and into motherhood, trust your instincts. They help keep you and your baby healthy and happy.
Your baby is developing so rapidly during the first trimester that you will want to be very careful with what you eat and what you are exposed to. Build a plan for solid prenatal nutrition.
Now is a great time to work on a good pregnancy diet focusing on fresh, natural foods. If nausea is already getting to you, "graze" on small, frequent meals. Start taking a quality prenatal vitamin.
First Trimester: Week 6
4 Weeks After Conception
The baby's brain and spinal cord start to form along with bones that will protect them. The beginnings of the face are also present.
Most organs, along with blood, blood vessels, and a heart have started forming. Your baby's heart begins to beat around the 25th day after conception. The yolk sac is nourishing your baby this week and the placenta continues to develop.
Your baby is also developing eyes and the earliest beginnings of ears. Your baby enters into a critical period for arm and leg development this week.
You might get a positive pregnancy test this week if you haven't already! It's a really exciting time for you and your baby. You may be feeling general mood swings or even periods of crying and tearfulness.
You will probably notice that you need to go to the bathroom more. Don't hold it - your tasks can wait a few minutes! Keeping your bladder empty is essential for keeping yourself healthy. It gets annoying to be peeing so frequently, but it's healthiest for you. After the first trimester you probably won't need to go so much.
Don't decrease your liquid intake either, eight cups of water a day for you! This helps your body to deal with your waste and eases the added stress on your liver that your body will undergo. You can also sip on milk or juices. It's best to stick to water or an herbal tea for most of your liquids.
Pregnancy discomforts are likely to be minor annoyances throughout your pregnancy, but you can look into natural ways of dealing with most of them.
First Trimester: Week 7
5 Weeks After Conception
This week the surface of your baby's skin is starting to develop. Sexual organs are developing, but they have not yet developed into testes or ovaries
Your baby's brain has divided into three main parts: the forebrain, the midbrain, and the hindbrain. The two hemispheres of your baby's brain are also visible this week. Your baby now measures 1/4 inch!
Your baby's body is undergoing vital development this week. His or her brain, body, and head are growing rapidly. A tiny mouth is forming on your little one, and within it is your baby's tongue.
Your baby doesn't need to take anything in through his or her mouth yet though, the umbilical cord is sending all the nutrients your body is providing right to your baby. Your diet is important for your baby. It gives him or her the vital nutrients needed to work through such rapid development.
Folic acid has been shown to be very beneficial to your baby, and can provide protection from some birth defects. You can get folic acid through your diet. Include plenty of fresh fruits and vegetables. A high quality prenatal vitamin will also have folic acid in it to support your baby's rapid first trimester growth.
If you are having trouble with morning sickness or nausea, continue to eat small, frequent meals. If you get sick, eat again. Your baby needs to you to keep eating well. Choose foods that give a lot of nutrition in a small package. Bland foods like yogurts and nuts give a lot of protein and other nutrients without much strong taste.
You may be able to get down fruit smoothies. Make your own with yogurt and fresh fruit (or fresh-frozen fruit) rather than buying store bought varieties or mixes, which contain un-natural additives. You can "sneak in" other supplements through smoothies as well, such as a powdered prenatal vitamin.
First Trimester: Week 8
6 Weeks After Conception
The baby's face, arms, and legs continue to develop. Fingers and toes begin to form this week, and baby has handprints and footprints. The baby's "tail" is nearly gone. The brain is in control of the body and controlling the development of the baby. Your baby's pituitary gland is also forming this week.
Baby's skeleton is complete but still soft cartilage and baby teeth are forming under your baby's gums. Your baby's intestines are forming within the umbilical cord. They will move into your baby's body once he or she is big enough to hold them.
You may be experiencing mood swings or apprehension, even if you were planning this pregnancy. It is normal to feel unsure about becoming a parent for the first time, or about becoming a parent again. Try journaling your feels or talking with someone you can trust.
You may feel sick and tired in the first trimester, which can make it even harder to deal with changing feelings. Be easy on yourself. Continue to eat well and get the rest that you need.
Have you shared the news? Some women want to tell everyone as soon as they find out they are pregnant. Others want to wait until the end of the first trimester. As the first trimester closes, your risk of miscarriage decreases greatly. You can choose to tell people about your pregnancy as soon as you feel ready. If you want to spill the beans, go right ahead! If you want to wait, that's ok too.
First Trimester: Week 9
7 Weeks After Conception
Baby is sensitive to touch this week! In the next week or so your baby will develop either testes or ovaries giving a physical indication of sex. It will still be many weeks before gender is discernible by ultrasound scan, however.
Your baby's limbs are becoming more proportional to the body and elbow and knee areas are starting to be discernible. Your baby's body will begin to straighten out some.
Your baby's heart has separated into four chambers by this week, which is a big accomplishment. The four-chambered heart allows for internal temperature regulation. Animals with only two chambers must rely on outside assistance (such as the sun) to regulate their temperature.
Your baby's brain isn't yet developed enough for temperature regulation, and even after he or she is born, you will still need to help keep baby warm. But a four chambered heart means that it won't be long before your baby can effectively regulate his or her own temperature.
Kegel exercises strengthen your pelvic floor and pregnancy is a great time to get into the habit of doing them. They are simply an intentional contraction and relaxation of the pelvic floor muscles and help prepare those muscles for the birth of your baby.
Your midwife may talk to you about them. If you are planning to take Bradley Classes then you will learn about them in detail! Natural Childbirth the Bradley Way covers many exercises you can incorporate into your day to strengthen your body for a natural birth.
First Trimester: Week 10
8 Weeks After Conception
The retina of your baby's eye is fully pigmented this week. Your baby has fingers and a thumb, though they are webbed, and there are small grooves forming for toes. Your baby's external ears have been developing along with his or her eyelids and tongue! A Child is Born has amazing pictures of this stage of your baby's development if you enjoy following along. Your baby's head has a rounded look now.
This week your baby has the distinction of being called a fetus instead of an embryo. Within the next couple of weeks risks to your baby decrease somewhat. The risks of some birth defects and congenital malformations will drop after this week. Your risk of miscarriage will begin to drop dramatically and will be very small by the end of the first trimester.
Your clothes may be starting to feel a little tight around your abdomen. Choose pants with a loose fit or an elastic waist if you need to. Pick something comfortable that doesn't restrict your circulation.
You may be longing to be past the first trimester and looking forward to a "bump" that will allow you to wear maternity clothes. Your uterus is about the size of a tennis ball by the end of this week, though your baby is still very tiny.
Or you might still be feeling a lot of morning sickness and simply be wishing that you were farther along to be over it! Remember to eat small, frequent meals and foods that offer a lot "nutritional bang for their buck."
First Trimester: Week 11
9 Weeks After Conception
Your baby is growing rapidly now. He or she has been growing quickly before now, but a lot that growth was organs and body systems developing. Your baby's bones and muscles are growing quickly and your baby begins to take on the proportions that he or she will have as a newborn.
If your baby is a girl, her vagina is forming this week, and if your baby is a boy, his penis is forming (though ultrasound cannot tell sex in the first trimester.) Your baby's posture is more upright this week.
Continue your excellent self care this week. You may be getting over any nausea you've been feeling, or you may still feel sick. Normal household tasks may make you feel ill. It is best for you and for your baby if you are careful about what you eat and about what you use around the house. Try and select natural cleaning products if you can. They smell better, and they don't emit harmful fumes.
You may want to begin taking pictures of your belly every few weeks if you haven't already. "Belly pics" will probably be very special to you after your baby is born. Most women remember their pregnancies fondly and like to look at how their belly grew from the first trimester onwards.
First Trimester: Week 12
10 Weeks After Conception
Nails and hair are forming on your baby. Genitals are well formed and distinguish boys from girls. Your baby is starting to urinate to clear wastes. Your baby's pancreas, gall bladder, and thyroid are each going through major growth.
Parts essential to your baby's future digestive process are developing this week - the hard palate and the muscles in the walls of your baby's digestive tract.
Your baby's skin is very thin and translucent. If you could see your baby, you would be able to see all his or her veins and blood vessels running under the skin. Your baby is still tiny, he or she could fit in the palm of your hand. However, your baby has grown an amazing amount since the microscopic little being he or she was at conception!
Your body is processing your baby's wastes. As he or she excretes urine, it is filtered out of the amniotic fluid by the placenta. Your body then deals with it along with your own waste.
Support your liver with good nutrition as it does double duty during pregnancy. Eat leafy greens, vitamin C rich foods, and yellow pigment foods to help your liver get its work done. Protein is also very important, even in the first trimester.
Continue to graze if you're still feeling nauseous. Your appetite may be picking up as you move through the first trimester. Eat nutrient dense foods and don't worry about weight gain. Cut out junk foods if you feel the need to cut something out!
First Trimester: Week 13
11 Weeks After Conception
Baby's intestines are beginning to move from the umbilical cord, where they formed at the beginning of the first trimester, into the abdomen! Your baby's vocal cords are forming this week. The liver and gall bladder are beginning to function.
Even though baby's systems are beginning to function, you are still keeping everything going for him or her. All of the nutrients you take in move through the placenta to your baby. It is a myth that your baby will steal your nutrient reserves - baby might get something, but it's going to leave both of you without what you need for healthy growth.
Be sure that you are eating a good pregnancy diet. You probably still have to pee a lot - go when you need to!
Does your skin seem more sensitive? It may be. During pregnancy your skin will get more sensitive even as your nails and hair may be growing stronger. Choose gentle skin care products. If you are going to be out in the sun use a higher SPF sunblock than you normally do.
First Trimester: Week 14
12 Weeks After Conception
Baby is three inches long. He or she is starting to be more active and can swallow a little bit. Baby is also practicing inhaling and exhaling, so there is fluid in the lungs. You can probably hear your baby's heartbeat with a Doppler this week! You may have been able to hear it earlier if you opted for an ultrasound.
You are in the last week of your first trimester. This trimester can seem to fly by. Hopefully you're over your nausea, but if you're still dealing with morning sickness, try and take it easy. Get plenty of fresh air and try to stick to easy-to-eat foods.
You may notice that your veins have taken on a darker, lacy pattern across your breasts and abdomen, and the area around your nipples (the areola) may have darkened. You might also be noticing a little "pooch" where your belly is starting to protrude!
Some women don't "show" for a long time, and some show much earlier. Congratulations making it through the first trimester! On to the second trimester - often the favorite!