The Second Trimester (Weeks 13–27): The Blooming Phase
The second trimester is often referred to as the "blooming phase" of pregnancy because many women experience a noticeable improvement in how they feel. As you move into weeks 13–27, symptoms like morning sickness and fatigue that were common in the first trimester tend to subside, and you may start feeling more energetic. This is the time when the baby’s growth accelerates, and physical changes become more apparent. The baby bump becomes more prominent as the uterus expands to accommodate your growing baby, and you may start feeling the first flutters of movement around weeks 18–20. This is also when your appetite may increase as your body requires more calories to support the baby’s development. The baby’s organs continue maturing, and they may start to hear sounds from the outside world. This is a time when many mothers report feeling more connected to their baby and more comfortable in their pregnancy. However, as your body changes, you might experience new symptoms such as backaches, leg cramps, heartburn, and swelling. It’s important to continue managing your health through balanced nutrition, regular exercise, and hydration while maintaining regular prenatal visits. This phase is often the most enjoyable as the initial discomfort of early pregnancy eases, and the excitement of your growing baby becomes more tangible.
Week-by-week breakdown of baby growth during the second trimester Week 13: The baby is about the size of a peach (around 2.9 inches long and weighs about 0.81 ounces). The baby’s fingerprints are beginning to form, and the thyroid gland starts producing hormones. The baby can make small, jerky movements, though you won’t be able to feel them yet.
Week 14: The baby is roughly the size of a lemon (about 3.4 inches long and weighs about 1.5 ounces). The face starts to look more defined, with the eyes moving into their correct position, and the baby’s kidneys begin producing urine. Hair follicles are forming, and the baby’s body starts growing faster than the head.
Week 15: Your baby is about the size of an apple (around 4 inches long and weighs about 2.5 ounces). Bones in the inner ear are developing, allowing the baby to begin hearing sounds from the outside world. The baby may begin to move more, but you won’t feel it just yet.
Week 16: The baby is now the size of a pear (around 4.6 inches long and weighs about 3.5 ounces). The baby’s eyes are beginning to make small, side-to-side movements, and hair starts growing on the scalp. The baby’s muscles and bones continue developing.
Week 17: Your baby is about the size of a turnip (around 5.1 inches long and weighs about 4.9 ounces). The baby is moving more actively, and you might begin to feel the first fluttering movements known as quickening. The baby’s bones are hardening, and the baby may even begin sucking on their thumb.
Week 18: The baby is about the size of a sweet potato (around 5.6 inches long and weighs about 6.7 ounces). The baby’s ears are now functioning, and they can hear sounds like your heartbeat and voice. The baby’s skin is still translucent, but fat begins accumulating under the skin.
Week 19: Your baby is about the size of a tomato (around 6 inches long and weighs about 8.5 ounces). Eyebrows and eyelashes have fully formed, and the baby is actively moving, stretching, and turning. The baby’s liver and spleen are working to produce red blood cells.
Week 20: The baby is about the size of a banana (around 6.5 inches long and weighs about 10.5 ounces). This marks the halfway point of the pregnancy! The baby has developed eyebrows, and their skin is becoming less translucent. The baby’s muscles and nervous system are developing rapidly, and you may feel their first kicks or movements.
Week 21: The baby is about the size of a pomegranate (around 10.5 inches long and weighs about 12.7 ounces). The baby is moving a lot more and has developed more defined skin. Their immune system is also starting to develop as they begin to produce white blood cells.
Week 22: Your baby is about the size of a spaghetti squash (around 10.9 inches long and weighs about 15.2 ounces). The baby’s skin is becoming less translucent, and fat deposits are starting to form beneath the skin. The baby’s bones are hardening, and their organs are maturing.
Week 23: The baby is about the size of a grapefruit (around 11.4 inches long and weighs about 1 pound). Their taste buds are fully developed, and they can move their eyes. The baby is starting to practice breathing, though the lungs are still immature.
Week 24: The baby is about the size of an ear of corn (around 12 inches long and weighs about 1.3 pounds). The baby’s skin is still wrinkled but is starting to form a layer of fat. The baby is moving more vigorously, and their lungs continue developing.
Week 25: The baby is about the size of a rutabaga (around 13 inches long and weighs about 1.5 pounds). The baby’s skin has developed some pigment and may be reddish in color. The baby’s eyes are now fully formed and can respond to light, and the baby’s lungs are continuing to mature.
Week 26: Your baby is about the size of a head of lettuce (around 14 inches long and weighs about 1.7 pounds). The baby’s brain is growing quickly, and their eyes are now opening and closing. Their lungs are preparing for breathing, and the baby can begin to recognize sounds.
Week 27: The baby is about the size of a cauliflower (around 14.5 inches long and weighs about 2 pounds). At this point, the baby is developing more fat stores, which will help them regulate their body temperature after birth. The baby’s lungs and brain are maturing, and they continue to practice breathing movements.
2. Mom’s body changes during the second trimester:
As the second trimester progresses, a mother’s body undergoes visible and physical changes. The most noticeable change is the growing belly, as the uterus expands to accommodate the rapidly developing baby. By the end of the second trimester, many women begin to show a more pronounced baby bump. This expansion can also put pressure on the lower back, leading to backaches. The ligaments and muscles in the back stretch and adjust to support the growing uterus, causing discomfort for many moms. Around weeks 18–20, most women start to feel baby kicks—a fluttering or gentle tapping sensation in the abdomen. These movements can become more pronounced as the baby grows, offering an exciting connection between mother and baby. The physical changes during this trimester, while sometimes uncomfortable, also mark the transition to a more active and visible pregnancy phase.
3. important tests and scans during the second trimester:
During the second trimester, there are several key tests and scans that provide important information about both the baby’s development and the mother’s health. One of the most significant is the anatomy scan (also known as the 20-week ultrasound), typically performed around weeks 18–22. This detailed ultrasound checks the baby’s growth, the development of their organs, and the structure of the heart, brain, spine, and other essential organs. It also helps confirm the baby’s sex (if you wish to know) and can detect any potential structural abnormalities. Another important test in the second trimester is the glucose screening (usually done between weeks 24–28), which tests for gestational diabetes. During this test, the mother drinks a sugary solution, and blood is drawn an hour later to check how well her body processes sugar. If the results are higher than normal, a follow-up test called the glucose tolerance test may be recommended. Additionally, some women may undergo the quad screen (or quadruple screen) between weeks 15–20, which is a blood test that measures four substances in the mother’s blood to assess the risk of certain conditions like Down syndrome, trisomy 18, and neural tube defects. These tests and scans help ensure the health of both mother and baby and can provide early detection of any issues that may require further evaluation or intervention.
4. Tips for moms during the second trimester:
The second trimester is a great time to focus on preparing for the arrival of your baby while still maintaining a healthy and active pregnancy. Staying active is important for your overall well-being, and gentle exercises like walking, swimming, or prenatal yoga can help reduce discomfort, alleviate back pain, and improve circulation. Always consult with your healthcare provider before starting any new exercise routine to ensure it’s safe for you. As your energy levels rise, it’s also a good time to begin preparing the nursery. Whether you’re organizing the space, picking out baby furniture, or setting up the crib, creating a cozy and functional environment can be a fun and fulfilling task. Another key aspect of this trimester is connecting with your baby. You can start bonding with your baby by talking to them, singing, or playing calming music, as your baby can hear sounds from the outside world. You may also begin feeling more regular baby movements, which can deepen your emotional connection. Taking time for relaxation and embracing these small moments of connection can help you mentally and emotionally prepare for the exciting months ahead.
5. Mind & Mood Corner for the second trimester:
The second trimester is often a time when many expectant mothers begin to feel more like themselves again after the fluctuations of the first trimester. However, while physical symptoms like morning sickness may subside, emotional shifts can still occur. Hormonal changes, along with the excitement and stress of pregnancy, can lead to mood swings. It's normal to feel periods of elation and joy as the pregnancy becomes more visible and tangible, mixed with moments of anxiety or uncertainty as you approach the second half of your pregnancy.
During this time, emotional check-ins are essential. Regularly reflecting on how you’re feeling can help you identify patterns or shifts in your mood. If you’re feeling unusually sad, overwhelmed, or stressed, it's okay to acknowledge it and take action. Coping mechanisms like mindfulness, deep breathing exercises, and talking to a partner or a friend can help reduce anxiety and bring a sense of balance. Additionally, staying active, practicing self-care, and celebrating small milestones in the pregnancy can positively impact your emotional well-being. It’s also important to communicate openly with your healthcare provider if you feel that your emotions are affecting your mental health significantly. If feelings of depression, extreme anxiety, or isolation persist, it’s important to seek support, as mental health is just as crucial during pregnancy as physical health.
6. Key Nutrients for the Second Trimester:
Weeks 13–16: During this early part of the second trimester, the baby’s organs are developing rapidly, and their bones are hardening. It’s essential to support bone and muscle growth with calcium and protein. Foods rich in calcium, such as dairy products (milk, yogurt, cheese), leafy greens (like kale and spinach), and fortified plant-based milks, are beneficial. Additionally, protein is crucial to support your growing baby, so aim to include lean meats, eggs, beans, nuts, and tofu in your meals. Don’t forget to include folic acid, found in whole grains, lentils, and fortified cereals, as it continues to support neural tube development.
Weeks 17–20: At this stage, your baby’s skin is developing, and fat deposits are beginning to form under the skin. To support this, focus on healthy fats. Omega-3 fatty acids are especially important for brain development, so include fatty fish (like salmon, sardines, and mackerel), chia seeds, flaxseeds, and walnuts in your diet. Vitamin C becomes important for skin, tissues, and iron absorption. Incorporate citrus fruits (oranges, grapefruits), bell peppers, broccoli, and strawberries into your meals. Additionally, continue prioritizing iron-rich foods like lean meats, beans, and spinach, as your blood volume is increasing during this stage.
Weeks 21–24: Your baby’s muscles and bones are continuing to strengthen, so calcium, magnesium, and protein remain important. Magnesium-rich foods like avocados, nuts, seeds, and whole grains can help support your baby’s bone development and ease potential leg cramps. Vitamin D also plays a role in calcium absorption, so try to get safe sun exposure or consume fortified foods (like fortified dairy, cereals, or orange juice). Stay hydrated and include high-fiber foods, such as whole grains, fruits, and vegetables, to help prevent constipation, a common issue during this stage.
Weeks 25–27: As your baby’s lungs mature and they begin to practice breathing, continue to prioritize vitamin A and vitamin C, which are key to the development of your baby’s lungs and immune system. Foods like carrots, sweet potatoes, apricots, and leafy greens are rich in vitamin A, while berries, kiwi, and tomatoes provide vitamin C. Iron intake remains vital to support the increased blood supply and prevent anemia, so continue consuming lean meats, beans, iron-fortified cereals, and green leafy vegetables. It’s also important to stay hydrated to support both your body and the amniotic fluid surrounding your baby.
Throughout the second trimester, make sure to eat a variety of nutrient-dense foods, as this helps support both your health and your baby’s development. Maintaining a well-rounded diet will also give you the energy you need to feel your best!