The second trimester of pregnancy runs from week 13 through the end of week 27. That’s roughly 15 weeks in the middle stretch of pregnancy, sandwiched between the often-difficult first trimester and the physically demanding third. Most people consider it the most comfortable phase of pregnancy, as nausea and exhaustion tend to fade while the belly is still manageable in size.
How the Trimesters Break Down
Pregnancy is divided into three trimesters based on a 40-week timeline counted from the first day of your last period. The first trimester covers weeks 1 through 12, the second covers weeks 13 through 27, and the third runs from week 28 until delivery. When your provider says you’ve entered the second trimester, it means you’ve completed 13 full weeks of pregnancy.
What Your Body Feels Like
The shift into the second trimester often brings noticeable relief. Morning sickness usually fades, the deep fatigue of early pregnancy lifts, and breast tenderness eases up. Many people describe a surge of energy that makes this stretch feel dramatically different from the first 12 weeks.
New symptoms replace the old ones, though. As the uterus expands, you may feel aching or sharp twinges along the lower sides of your belly from ligaments stretching to support it. The skin on your stomach can start to itch as it stretches, and hormonal shifts sometimes cause darker patches of pigmentation on the face or abdomen. None of these are cause for concern on their own, but they’re worth mentioning at a prenatal visit if they bother you.
Your belly becomes visibly pregnant during this trimester. Calorie needs increase by about 300 per day, bringing the daily target to roughly 2,200 calories for most people who started pregnancy at a normal weight.
How the Baby Grows
The growth that happens between weeks 13 and 27 is dramatic. At the start of the second trimester (around week 14), the baby measures about 3.5 inches from head to tailbone and weighs roughly 1.5 ounces. By week 26, near the end of the trimester, that same measurement is about 9 inches, and the baby weighs close to 2 pounds.
During these weeks, the baby develops from a small, translucent figure into something that looks and moves like a newborn. Organs continue to mature, fingers and toes become distinct, and the baby begins practicing movements like sucking and swallowing. Hearing develops during this window too, which is why some parents start talking or playing music to the belly in the second trimester.
When You’ll Feel the Baby Move
One of the biggest milestones of the second trimester is feeling fetal movement for the first time, sometimes called “quickening.” This typically happens between weeks 16 and 20, though the timing depends on whether you’ve been pregnant before. People in a second or later pregnancy often notice movement closer to 16 weeks because they recognize the sensation. First-time parents more commonly feel it around week 20.
Early movements feel less like kicks and more like fluttering, bubbles, or a light tapping. They’re easy to mistake for gas at first. The movements become stronger and more recognizable as the weeks go on.
Key Tests and Appointments
Two important screenings happen during the second trimester. The first is the anatomy scan, an ultrasound performed between weeks 18 and 22. During this appointment, a sonographer takes detailed measurements and images of the baby’s heart, brain, spine, kidneys, limbs, face, and other structures. They also check the placenta’s position, measure amniotic fluid levels, and look at blood flow through the umbilical cord. This is often the ultrasound where parents can learn the baby’s sex if they want to know.
The second major screening is the glucose challenge test, which checks for gestational diabetes. It’s done between weeks 24 and 28 for most pregnancies. You’ll drink a sugary solution and have your blood drawn afterward to see how your body processes the sugar. If results are elevated, a longer follow-up test confirms whether gestational diabetes is present. People with higher risk factors may be screened earlier.
Warning Signs to Take Seriously
While the second trimester is generally the smoothest stretch of pregnancy, certain symptoms need immediate medical attention regardless of the week. These include vaginal bleeding that goes beyond light spotting, fluid leaking from the vagina, severe or worsening abdominal pain, a persistent headache paired with vision changes, sudden swelling of the face or hands, fever of 100.4°F or higher, and a noticeable decrease in fetal movement once you’ve been feeling it regularly. Trouble breathing, chest pain, or a racing heartbeat also warrant urgent evaluation.