What to Expect as Your Pregnancy Progresses
The OB/GYN team at Rapid City Medical Center is proud to support women throughout every stage of pregnancy with compassionate, evidence-based care. We understand that pregnancy brings a wide range of physical, emotional, and developmental changes—for both you and your baby—and we’re here to guide you through each one with clarity and confidence.
In the first trimester, you may experience fatigue, nausea, breast tenderness, and frequent urination as your body adjusts to early hormonal shifts. The second trimester often brings renewed energy, noticeable belly growth, and the first flutters of fetal movement, along with skin changes and occasional ligament pain. By the third trimester, stronger fetal kicks, shortness of breath, and increased pressure in the pelvis are common as your baby prepares for birth.
Whether you’re preparing for your first prenatal visit, tracking your baby’s development, or managing common discomforts, our team is here to help. We offer personalized care, up-to-date resources, and a welcoming environment where your questions are always encouraged.
At Rapid City Medical Center, we believe that every pregnancy is unique and every patient deserves thoughtful, individualized care. Explore the information below to learn more about what’s happening each month and how we can support you along the way.
What to Expect as Your Pregnancy Progresses
The OB/GYN team at Rapid City Medical Center is proud to support women throughout every stage of pregnancy with compassionate, evidence-based care. We understand that pregnancy brings a wide range of physical, emotional, and developmental changes—for both you and your baby—and we’re here to guide you through each one with clarity and confidence.
In the first trimester, you may experience fatigue, nausea, breast tenderness, and frequent urination as your body adjusts to early hormonal shifts. The second trimester often brings renewed energy, noticeable belly growth, and the first flutters of fetal movement, along with skin changes and occasional ligament pain. By the third trimester, stronger fetal kicks, shortness of breath, and increased pressure in the pelvis are common as your baby prepares for birth.
Whether you’re preparing for your first prenatal visit, tracking your baby’s development, or managing common discomforts, our team is here to help. We offer personalized care, up-to-date resources, and a welcoming environment where your questions are always encouraged.
At Rapid City Medical Center, we believe that every pregnancy is unique and every patient deserves thoughtful, individualized care. Explore the information below to learn more about what’s happening each month and how we can support you along the way.
Months 1–2 (Weeks 1–8)
Fertilization and implantation occur.
The embryo begins forming the brain, spine, heart, and digestive tract.
Arm and leg buds appear; fingers and toes begin to form.
By week 8, the embryo is about ½ inch long.
Month 3 (Weeks 9–12)
Eyelids form, and the head becomes more rounded.
The fetus begins swallowing amniotic fluid and making urine.
Fingernails appear; breathing-like movements begin.
By week 12, the fetus is about 2 inches long and weighs ½ ounce.
Month 4 (Weeks 13–16)
All major organs are formed and continue to develop.
Bones begin to harden; the neck and limbs are more defined.
Hearing starts to develop; limb movements become more coordinated.
By week 16, the fetus is over 4 inches long and weighs more than 3 ounces.
Month 5 (Weeks 17–20)
The fetus can hear sounds and move more actively.
Facial features become more defined; lanugo (fine hair) begins to grow.
By week 20, the fetus is over 6 inches long and weighs under 11 ounces.
Month 6 (Weeks 21–24)
Kicks and turns become stronger; thumb-sucking may begin.
Eyebrows form; REM sleep begins.
Fingerprints and footprints start to develop.
By week 24, the fetus is about 12 inches long and weighs around 1½ pounds.
Month 7 (Weeks 25–28)
The fetus responds to familiar sounds and loud noises.
Lungs begin producing surfactant, essential for breathing after birth.
Vernix (a protective coating) forms on the skin.
By week 28, the fetus is nearly 15 inches long and weighs about 2½ pounds.
Month 8 (Weeks 29–32)
The fetus can stretch, kick, and grasp.
Eyes open and close; red blood cells form in the bone marrow.
Lanugo begins to disappear.
By week 32, the fetus is nearly 17 inches long and weighs just over 4 pounds.
Month 9 (Weeks 33–36)
- Rapid brain growth continues; bones harden, but the skull remains soft.
More fat forms under the skin; fingernails reach the fingertips.
Most babies turn head-down in preparation for birth.
By week 36, the fetus is about 18 inches long and weighs over 6 pounds.
Month 10 (Weeks 37–40)
The lungs, brain, and nervous system are fully developed.
The fetus takes up most of the space in the uterus.
By week 40, the baby is about 20 inches long and weighs 7½ to 8 pounds.
