Week 1: You’re not really pregnant yet; the clock starts ticking from the first day
of your last period. So even though pregnancies are said to be 40 weeks long, you actually carry your baby for only 38 weeks or so.
Read more about being 1 week pregnant.
Week 2: Ovulation occurs; ideally, sperm will already be lying (er, swimming) in wait.
Read more about being 2 weeks pregnant.
Week 3: Fertilization occurs in one of the fallopian tubes. Cell division begins at breakneck speed.
Your Growing Baby
Fertilization occurs in one of the fallopian tubes. Cell division begins at breakneck speed.
Though it's very early in your pregnancy, things are definitely happening! Once the "winning" sperm (one of 200 million or so contenders) has penetrated your egg, the egg shuts down, admitting no more sperm. Two sets of cell nuclei fuse together inside the egg, assigning your baby—now called a zygote—a gender, eye and hair color and more than 200 other genetically determined characteristics.
Your Growing Belly
Be sure that you're taking good care of your baby. Now, if not before you started trying to conceive, you should:
Quit smoking.
Avoid alcohol.
Avoid drugs: the legal, the illegal, and those labeled "herbal supplements," and those that come as skin creams (such as acne medication) and in beverages (like caffeine).
Immediately tell your care provider about any prescription or other medications you currently take or were taking at the time you conceived.
Avoid taking large amounts of vitamins: an over-the-counter prenatal or even daily chewable (like a Flintstone) is enough and is recommended for all women who are trying to conceive or who could possibly become pregnant.
If you have any kind of medical appointment with a doctor or dentist, inform them that you may be pregnant.
Eat five servings of different fruits and vegetables daily.
Drink plenty of water.
Week 4: The fertilized egg (known as a zygote) implants in the wall of the uterus; the placenta and umbilical cord begin to form.
Read more about being 4 weeks pregnant.
Week 5: The gastrointestinal tract, spinal cord, heart, brain, blood and blood vessels begin to form. The embryo is 1∕16 to 1∕8 inch long “crown to rump” (the measurement that’s used until week 13).
Read more about being 5 weeks pregnant.
Week 6: The heart begins to pump blood, and the neural tube that will become the spine closes (which is why taking folic acid early is essential). The embryo takes on a C-shape; arm and leg buds begin to form; and the skin is translucent. Length: about 1∕4 inch. Fetus fact: The heart will beat 54 million times before birth!
Read more about being 6 weeks pregnant.
Week 7: The head is about 1∕3 the size of the entire embryo. The brain and face are developing rapidly, and nostrils and lenses of the eyes begin to form. Arm buds become paddle-shaped; hands begin to form. Length: about 1∕3 inch.
Read more about being 7 weeks pregnant.
Week 8: Brainwave activity starts. Fingers and toes begin to form and are webbed. Lungs, ears, eyes, upper lip and nose start to form. The body is beginning to straighten, and subtle movements begin. Length: about 1∕2 inch.
Read more about being 8 weeks pregnant.
Week 9: The heart is almost completely developed. Eyelids are forming, as are hair follicles and nipples; the embryo can hiccup now. Fingers and toes are no longer webbed. The arms develop bones, and the hands begin to touch the face. The legs start to move. Length: about 3∕4 inch.
Read more about being 9 weeks pregnant.
Week 10: The developing baby is now called a fetus. The eyelids begin to fuse to protect the eyes. The fetus begins doing occasional breathing movements, although it gets oxygen through the umbilical cord. The skin becomes less translucent, and genitals begin to form. Length: almost 1 ¼ inches.
Your Growing Baby
The developing baby is now called a fetus. The eyelids begin to fuse to protect the eyes. The fetus begins doing occasional breathing movements, although it gets oxygen through the umbilical cord. The skin becomes less translucent, and genitals begin to form. Length: almost 1 ¼ inches.
Your Growing Belly
Congratulations, your uterus has swollen to the size of a softball! Looking in the mirror, your shape has definitely changed: less waist and more chest.
Breasts are busiest in the first trimester. During the first few weeks, progesterone causes milk glands to develop and estrogen stimulates
growth of the milk ducts. Breasts typically expand one or two bra cup sizes, veins get darker, and nipples get larger, more erect and darker so that eventually, the baby can find them easily.
Your
weight gain may be picking up—though don't worry if you haven't gained any by now. Bottom line, if your provider isn't concerned about how much or how little you've gained, you shouldn't be either.
Tips & To-Do's
Prenatal Testing
First-Trimester Screening
WHO IT’S OFFERED TO: All women.
WHEN IT’S OFFERED: At 10 to 13 weeks.
WHAT IT SCREENS FOR: Chromosomal defects such as Down syndrome and trisomy 18 (an often lethal defect); some cardiac defects.
HOW IT WORKS: Blood is drawn from the mother, and three fetal proteins are measured. These results are combined with the results of a detailed ultrasound (nuchal translucency) that measures the thickness at the back of the fetus’s neck.
HOW EFFECTIVE IT IS: It has an 80 percent to 85 percent detection rate for Down syndrome, with a 4 percent to 6 percent false-positive rate.
WHAT IF …? If you have a positive screen and are not comfortable with the odds, you may opt for a diagnostic test to determine if your baby has a defect. Another option is to do an additional screen in the second trimester—but this will not give you a definitive answer, either.
Week 11: Nearly all the organs and body structures are formed and beginning to function. Genitals begin to take on either male or female form. The head makes up about half of the fetus’s body. Length: about 2 inches. Fetus fact: The fetus can sigh, stretch, move its head and suck its thumb.
Your Growing Baby
Nearly all the organs and body structures are formed and beginning to function. Genitals begin to take on either male or female form. The head makes up about half of the fetus’s body. Length: about 2 inches. Fetus fact: The fetus can sigh, stretch, move its head and suck its thumb.
Your Growing Belly
Your body's expanding, inside and out. The next ten weeks will be a period of rapid growth for you and the baby. You'll need more water as you produce more blood, sweat, oil, and
amniotic fluid. You may feel desperately thirsty at times. It's a good idea to carry a beverage with you wherever you go, to keep your fluid levels up. Drink plenty of water and milk, but steer away from carbonated beverages.
Tips & To-Do's
10 (surprising!) Prenatal Power Foods
As you know, folate, fiber and iron are essential nutrients for you and your growing baby. What you may not know is that you can get all three by eating chives. Or, how about adding figs to your diet to boost your calcium intake? From
The 100 Healthiest Foods to Eat During Pregnancy, here are 10 unexpected (and delicious!) foods that will provide the nutrition you need during pregnancy.
Week 12: The face begins to look more human. Length: 3 inches (head to heel, the measurement from now on).
Your Growing Baby
The face begins to look more human. Length: 3 inches (head to heel, the measurement from now on).
She may weigh as much as half an ounce. This begins the age when the fetus starts to look really cut in those womb pictures. If you had a womb camera, you'd be able to see your baby's proportions changing, with the growth of the head slowing down to let the rest of the body catch up. Arms, legs, and fingers are also growing out and tapering to look more like a newborn's, and your baby's posture becomes less curled and more upright.
Your Growing Belly
This is about the time the muscles of your stomach slow down, making your stools harder and drier and making you gassier. You uterus has gotten too big to fit in its usual spot—your pelvis. It's now pushing into your abdomen, though not yet in any uncomfortable way. Your heart rate may speed up because of the extra volume of blood in your body. Your hips are actually widening to make more room for your uterus to grow.
With one week to go in your first trimester, you may feel more like your pregnancy is real. The magic end of the first trimester is at hand, which means it'll soon be time to tell your boss, co-workers, and distant relatives about your condition, if they haven't figured it out already. Take brisk walks, eat high-fiber foods, and drink plenty of water to keep your intestinal tract moving.
Week 13: The nose and lips are completely formed, and the fetus begins to produce and excrete urine.
Read more about being 13 weeks pregnant.
Week 14: The nose, lips and taste buds are formed. The head is covered by a fine, soft hair called lanugo. Length: about 5 inches; weight: about 2 ounces. Fetus fact: Starting now, female fetuses show mouth movements much more often than males.
Read more about being 14 weeks pregnant.
Week 15: The "window of opportunity" for many important screening and diagnostic tests opens this week, should you decide to undergo them.
Read more about being 15 weeks pregnant.
Week 16: Sometime between 16 and 22 weeks, you'll start to feel your baby move.
Read more about being 16 weeks pregnant.
Week 17: Your sleep may be marked by vivid and bizarre dreams, often reflecting anxiety you might have about childbirth and parenthood.
Read more about being 17 weeks pregnant.
Week 18: Fat is being deposited throughout the body. Teeth have started to form. The fetus begins to hear sounds in your body (such as your heart beating) and may even startle at loud noises. Length: about 8 inches; weight: 6 ounces.
Read more about being 18 weeks pregnant.
Week 19: Now that you're feeling better, it's time to spend some quality time with your partner. So have sex! Unless you're having complications, it's safe for most women throughout pregnancy.
Read more about being 19 weeks pregnant.
Week 20: A white, creamy substance called vernix caseosa protects the skin from its aqueous environment. Sweat glands form. Length: about 10 inches; weight: 9 ounces. Fetus fact: Starting now, immunities are being transferred from you to the fetus.
Read more about being 20 weeks pregnant.
Week 21: If you're 35 or older, have chronic high blood pressure or diabetes or are carrying multiples, you are at a higher risk of preeclampsia. It can occur this early, but usually doesn't set in until the third trimester.
Read more about being 21 weeks pregnant.
Week 22: The brain has entered a phase of extremely rapid growth. Length: about 11 inches; weight: just under 1 pound.
Read more about being 22 weeks pregnant.
Week 23: The testicles begin to descend into the groin from the abdomen; the uterus and ovaries have developed. Body proportions are similar to a newborn’s, though the fetus is still thin. The eyes are formed but lack pigmentation. Length: about 11 1∕2 inches; weight: about 1 pound.
Read more about being 23 weeks pregnant.
Week 24: The fetus develops waking/sleeping patterns. Real hair (not lanugo) begins to grow on the head. Length: about 12 inches; weight: 1 ¼ pounds. Fetus fact: If born now, your baby would have about a 50 percent chance of surviving.
Read more about being 24 weeks pregnant.
Week 25: You may be afflicted with heartburn and leg cramps, especially at night.
Read more about being 25 weeks pregnant.
Week 26: The eyelids separate and the eyes are starting to open. Lungs are beginning to develop surfactant, which allows them to inflate. The fetus begins to sleep for longer periods, often when you do. Length: 14 inches; weight: almost 2 pounds.
Read more about being 26 weeks pregnant.
Week 27: You may be distressed to see the numbers on the scale creep (OK, jump) up: From here on out, you'll probably be gaining about 1 pound a week. This still only translates to about 300 extra calories a day, though.
Read more about being 27 weeks pregnant.
Week 28: The fetus can taste and smell, and the eyes can produce tears. The bones are almost fully developed though stillsoft. Weight gain is rapid from now on. Length: about 15 inches; weight: more than 2 1∕2 pounds.Fetus fact: The brain will increase 400 percent to 500 percent in weight between now and delivery.
Read more about being 28 weeks pregnant.
Week 29: The basketball-sized lump in your belly may be inhibiting shoe tying, leg shaving and the like. The fetus is increasingly sensitive to light and sound.
Read more about being 29 weeks pregnant.
Week 30: You might find yourself increasingly breathless as your growing uterus crowds your diaphragm. It should ease a bit when the baby drops lower in your pelvis later in pregnancy.
Read more about being 30 weeks pregnant.
Week 31: All major organs except the lungs are completely developed. The eyes
are wide open.
Read more about being 31 weeks pregnant.
Week 32: The fetus practices breathing motions inpreparation for birth. All five senses are developed, and REM (dream-cycle) sleep is beginning. Lanugo begins to disappear. Length: about 17 inches; weight: about 4 pounds. Fetus fact: If your babywere born now, he would have an excellent chance of surviving without life-threatening complications.
Read more about being 32 weeks pregnant.
Week 33: Don't get too married to your dream delivery: Even if you're hoping for a vaginal birth, there's a nearly 1 in 3 chance you'll have a C-section.
Read more about being 33 weeks pregnant.
Week 34: The fetus is taking deep breaths. The eyes can blink and are open when it’s awake and closed when asleep, and the pupils dilate and constrict in reaction to light. Length: about 18 inches; weight: about 5 pound.
Read more about being 34 weeks pregnant.
Week 35: There's a good chance your body harbors Group B streptococcus bacteria without your knowing it. If it colonizes in the vagina and is left untreated, it can infect your baby at birth.
Read more about being 35 weeks pregnant.
Week 36: The baby may drop lower into your pelvis in preparation for delivery. This should make it easier to breathe—yet your pee breaks will become ever more frequent.
Read more about being 36 weeks pregnant.
Week 37: Activity levels are consistent and predictable, and the organs are ready to function on their own. The fetus may move to the headfirst position in preparation for labor. Length: about 19 inches; weight: about 6 pounds. Fetus fact: The baby will gain about 1∕2 pound per week until delivery.
Read more about being 37 weeks pregnant.
Week 38: Your pregnancy is considered full-term now, and the lanugo—the downy hair that covered your baby's body—is starting to disappear.
Read more about being 38 weeks pregnant.
Week 39: Lanugo has almost completely disappeared. The fetus drinks approximately 15 ounces of amniotic fluid per day, and hiccups are common. Testicles begin todescend from the groin into the scrotum; the labia are well-developed.
Read more about being 39 weeks pregnant.
Week 40: The body is 15 percent fat. The lungs will continue developing until the baby is born.
Read more about being 40 weeks pregnant.
