What is the second trimester?
The first three months of pregnancy can be the hardest for moms-to-be. But the next three months, or the second trimester of pregnancy, might be the easiest for you. This “golden period” is the most enjoyable stage of pregnancy.
The second trimester is the middle stage of pregnancy. It lasts from the fourth to the sixth month or 13 to 28 weeks of pregnancy. During this stage, your body will undergo many changes and your baby will grow quickly. You’ll start seeing your “baby bump” and feel your baby’s movements.
The fatigue, morning sickness, and other unpleasant symptoms you experienced in the first trimester will fade during your second trimester. With restored energy and a renewed sense of well-being, you’ll begin to feel your best.
The pregnancy second trimester stages will be the most comfortable part of pregnancy. This is also the ideal time to learn about the next trimester and plan your baby’s birth.
Changes you experience in the second trimester
During your second trimester of pregnancy, you’ll have increased energy, a better appetite, decreased nausea, and improved sleep patterns. But you will likely experience some of the following symptoms due to hormonal changes:
- Growing belly and increased breast size
- Body pain in the lower back, abdomen, pelvis, or legs
- Pigmentation or dark patches on your face, known as melasma
- A dark line along your abdomen, or linea nigra
- Darkening of the area around your nipples
- Stretch marks across your abdomen, breasts, buttocks, or thighs
- Swelling or bleeding of mucous membranes in your nose, causing congestion or nosebleeds
- Sensitive or bleeding gums
- Dizziness due to changes in blood circulation
- Leg and abdominal cramps
- Sticky, clear, or white vaginal discharge
- Numbness or tingling in your hands, known as carpal tunnel syndrome
- Itchy abdomen, palms, and feet
- Swelling in your ankles, fingers, or face
Most of these symptoms go away after delivery. You may also experience mild, irregular contractions in your abdomen. These are called Braxton Hicks contractions or false labor.
Contact your doctor if you have painful urination, as it may be a sign of urinary tract infection. You may also have to undergo second-trimester prenatal checkups for:
- Unusual symptoms or discomforts
- Your weight and blood pressure
- Urine test to check for urinary tract infection, preeclampsia or high blood pressure, and blood sugar
- Your baby’s growth and heartbeat
- The size of your uterus
Your baby in the second trimester
At the start of the second trimester, your baby will be 4 inches long and weigh approximately 1 ounce. During this stage, your baby undergoes the following changes over the course of three months.
From 13 to 16 weeks of pregnancy
During this period, your baby’s muscles grow and bones harden to create the musculoskeletal system. Skin starts to form, but it is almost thin enough to see through. You will also start seeing toenails.
Lungs begin to develop slowly. Your baby starts showing signs of sucking and swallowing reflexes. Your baby’s first stool, known as meconium, starts developing in the digestive tract.
Your baby grows to 4 or 5 inches and weighs approximately 3 to 4 ounces.
From 17 to 20 weeks of pregnancy
You will feel your baby move in your womb as it becomes more active in this period. Fine, soft hair called lanugo and a waxy coating called vernix cover your baby to protect the growing skin. These eventually get absorbed into your baby’s skin.
By now, your baby’s ears, nose, lips, eyebrows, eyelashes, and nails will be visible on ultrasound. The digestive system starts working, and parts of the brain that control movement are formed.
Halfway through the pregnancy, your baby will grow to 6 inches and weigh 9 ounces.
From 21 to 24 weeks of pregnancy
Your baby can now kick and turn. The sucking reflex continues to develop, and the hand and startle reflexes develop. Taste buds, footprints, and fingerprints form. Hair begins to grow on your baby’s head. Blood cells begin to form in the developing bone marrow.
Fat slowly forms under the skin, so your baby gains weight during the second trimester. The skin is now wrinkly and reddish. Your baby also has a sleep cycle, with regular sleeping and waking patterns.
Your baby’s sex organs are also developing in this stage. If you wish to determine your baby’s sex, you can do so in the second trimester.
Growing to about 12 inches, your baby will now weigh 1.5 pounds.
From 25 to 28 weeks of pregnancy
At this stage, your baby’s lungs are completely developed but can’t function in the womb. Hand and leg movements are now stronger. Your baby can open and close their eyelids.
The nervous system gradually develops. As more fat forms under the skin, the wrinkly skin begins to look smooth.
By this time, your baby will be 13 to 16 inches long and weigh between 2 and 3 pounds.
Precautions you can take
In your second trimester of pregnancy, eat a healthy diet with more fruits and vegetables for fiber and drink lots of water. Avoid strenuous exercise, alcohol, and smoking. Consult with your doctor before taking any prescription drugs or supplements.
Health Solutions From Our Sponsors
ACOG: "How Your Fetus Grows During Pregnancy."
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