First pregnancy milestones

Sep 15, 2011 at 6:08 p.m. ET

Every woman’s pregnancy is different. Her first can be drastically different than her second. Some women never experience so much as a bout of heartburn and barely gain a pound while others find themselves constantly queasy, irritable and seem to gain weight like it’s going out of style.

your pregnancy month by month

So what will your pregnancy be like? There's no way to know for certain until you go through it, because every woman is different and every baby develops differently. But here's a general map of what you can expect for yourself and your baby each month.

The First Month (weeks 1-4)

• You'll likely find out you're pregnant. During the last week of this month you'll miss your period. After you've missed your period, home pregnancy tests can be taken with the best chance of an accurate result.

• Follow up your positive pregnancy test with a visit to your doctor to confirm the results and start your prenatal care.

• The placenta (which provides nutrients to you and your baby) is developing.

• Your baby's organs are beginning to develop.

• By the end of this month, your baby is the size of a poppy seed.


    The Second Month (weeks 5-8)

    • At the beginning of this month, if you haven't taken a test yet, you might start to think you're pregnant. Symptoms include sore breasts, frequent urination and nausea ("morning sickness"). Take a pregnancy test to confirm.

    • The placenta continues to form. Your baby's spinal cord, heart, brain, muscle and bones are developing.

    •You're either losing or gaining weight depending on how sick you've been feeling.

      • Your baby's heartbeat could be detected this month.

      • Your baby's eye buds, limb buds, leg buds, eyelid folds and even his nose are developing. And his heart and lungs are becoming even more developed.

      • By the end of this month, your baby will be about the size of a grape; he is still considered an embryo.


        The Third Month (weeks 9-12)

        • Your baby is moving its limbs and body but you can't feel it yet (maybe next month).

        • By the middle of this month, your baby will be called a fetus and looks like a shrimp.

        • Toward the end of this month, your baby's heartbeat can be heard (sounds like swishing) on a Doppler (sound-wave stethoscope).

        • Your baby has started swallowing and is developing reflexes.

        • You might notice changes to your hair and nails (usually for the better).

        • By the end of this month, your baby is completely formed, will continue to grow bigger and stronger. She's about the size of a lime.


          The Fourth Month (weeks 13-16)

           • At the beginning of this month, you've officially started your second trimester.

          • Your baby's intestines are shifting into place.

          • Your baby's ears, which are on the neck, start moving toward the side of the head).

          • You'll likely start wearing maternity clothes sometime this month.

          • You might feel your baby move. It's very slight and feels almost like gas or fluttering. Many women don't feel the baby until closer to or around 20 weeks, however.

          • Your baby's eyelids, eyelashes, eyebrows, fingernails and toenails and hair are formed.

          • Your baby can suck its thumb and even frown.

          • By the end of this month, your baby is about the size of an avocado.


            The Fifth Month (weeks 17-20)

            • Your baby's sweat glands are developing.

            • Your center of gravity is changing, so you might feel off-balance.

            • Having a girl? Her uterus and Fallopian tubes are formed. Having a boy? His genitals can be detected in imaging.

            • You could start to feel a lot hungrier this month.

            • It is believed that your baby can start to hear you this month.

            • You might experience round ligament pain in your abdomen from your ligaments stretching to support your uterus.

            • Toward the end of this month your baby is producing meconium - black and sticky, a result of digestion. It gathers in his bowels and you may see it in his first diaper if not sooner (during delivery).

            • You're at the halfway mark in your pregnancy.

            • At the end of this month, your baby is the length of a banana.


              The Sixth Month (weeks 21-25)

              • Your baby's movements will start to feel less like gas and more like kicks

              • Having a girl? Her vagina has started to form.

              • You might be getting acne (due to extra amounts of oil produced by your body), varicose veins (increased pressure on the veins in your legs) and/or stretch marks -- among many other things, including heartburn, increased flatulence, leg cramps and dizziness.

              • Your baby's nerve endings are developing, so she might reach for her face or other parts of her body to explore her sense of touch.

              • Your baby' wrinkled skin won't hang so loosely anymore, as she begins accumulating baby fat. She's beginning to look more human.

              • By the end of the month, your baby will be the size of a rutabaga.


                The Seventh Month (weeks 26-30)

                • Your baby is inhaling and exhaling amniotic fluid, which is helping his lungs develop.

                • Having a boy? Your son's testicles are beginning to descend.

                • Your baby will probably have the hiccups often.

                • If you haven't already, you might begin to experience cramping in your legs.

                • Toward the end of this month, your baby's eyesight is developing and he may be able to see light coming into the womb.

                • You might experience "restless leg" syndrome, where you have the urge to move your legs when you're trying to sleep or relax.

                • You might experience mood swings as a result of all of the hormonal changes.

                • At the end of this month, you're in the third trimester.

                • At the end of this month, your baby is the size of a head of cabbage.


                  The Eighth Month (weeks 31-34)

                  • Your uterus is filling most of your abdomen.

                  • Up until now, you've been seeing your OB-GYN monthly. Now, you'll begin seeing him or her every two weeks.

                  • Your baby will begin to move less because of tight quarters.

                  • By the end of this month, your baby will be the size of a cantaloupe.


                    The Ninth Month (weeks 35-40)

                    • You're in the home stretch.

                    • Your baby's kidneys are fully developed.

                    • Your baby will continue to gain weight

                    • Your growing uterus now reaches up to your rib cage. It's also squeezing your internal organs, which could cause you to have to urinate frequently and might also give you heartburn.

                    • You'll start seeing your OB-GYN every week.

                    • At the end of the 37th week, your baby will be considered full-term.

                    • Most likely your baby is in the head-down position.

                    • Because your baby has gotten so big, you're probably eating much smaller meals.

                    • Your baby is receiving antibodies from you to protect him from illness.

                    • Only 5 percent of babies are born on their due date, so as yours approaches, try to be patient.


                    More on Pregnancy

                    Common prenatal procedures

                    20 Things to add to your baby registry

                    What birth is really like: The naked truth