Week 1You're actually not 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 only carry your baby for 38 weeks. Read more about being 1 week pregnant.
Week 2Ovulation occurs. For the best chances of getting pregnant, have sex one to two days before your expected ovulation date. Read more about being 2 weeks pregnant.
Week 3You may be pregnant but probably won't have any symptoms. Read more about being 3 weeks pregnant.
Week 4Positive test: You're pregnant! You may be starting to feel bloated, crampy, tired and moody, and experiencing sore breasts, nausea/vomiting and a frequent need to pee. But don't worry if you're not—that's normal. Read more about being 4 weeks pregnant.
Week 5Though the embryo is only about the size of a grain of sand, the heart is pumping blood, most other organs have begun to develop, and arm and leg buds appear. You may be starting to experience "pregnancy brain." Read more about being 5 weeks pregnant.
Week 6Now that the pregnancy is feeling more real, you might be worrying about miscarriage. Read more about being 6 weeks pregnant.
Week 7The embryo doubles in size but is still less than a half-inch long. As your pregnancy hormones increase, morning sickness may be worsening. Or, you may be ravenous 24/7. Read more about being 7 weeks pregnant.
Week 8Your doctor may look or listen for the baby's heartbeat with an ultrasound. Once you see or hear it, your miscarriage risk drops to about 2 percent. He'll also give you an official due date—though very few women actually deliver on that day. Read more about being 8 weeks pregnant.
Week 9The pressure of your growing uterus on your bladder may cause you to leak small amounts of urine. Read more about being 9 weeks pregnant.
Week 10Your inch-long baby is now called a fetus. While the icky side effects of pregnancy may be starting to abate, your anxiety about having a healthy baby might be increasing. Read more about being 10 weeks pregnant.
Week 11Your cravings may run the gamut from cheeseburgers to chalk (really!). Weird nonfood cravings are known as pica and can reflect a deficiency in your diet. This week, nearly all of the fetus's organs are beginning to function, and genitals begin to take on male or female form. Read more about being 11 weeks pregnant.
Week 12Your uterus has begun to expand outside the protective pelvic bones. It will increase in size by almost 1,000 times by the end of your pregnancy! You may really be starting to show now, especially if it's not your first baby. Read more about being 12 weeks pregnant.
Week 13Now that you've finished your first trimester, you can start eating for two—a little. Plan on gaining about 12 pounds during the next 14 or so weeks. Read more about being 13 weeks pregnant.
Week 14Your renewed energy (and end to morning sickness) may lull you into thinking you can take on a marathon, but follow this guideline: Work out only so hard that you can carry on a conversation without getting out of breath. Read more about being 14 weeks pregnant.
Week 15The "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.