Second Trimester
Medically reviewed by Samantha L. Fox, RN, BSN, MSN
Nursing Informaticist · United States Navy Nurse Corps · Last reviewed
Weeks 13–27 · The Golden Trimester
Welcome to the golden trimester! For most people, the second trimester brings welcome relief from early pregnancy symptoms. Nausea usually fades, energy returns, and you'll start to feel and look visibly pregnant. This is also when you'll have your anatomy scan, possibly learn your baby's sex, and feel those first magical movements — called quickening.
Key Milestones
End of the First Trimester
Miscarriage risk drops significantly. Nausea begins to ease for most. Time to share the news!
First Movements (Quickening)
You may feel subtle flutters, bubbles, or gentle taps — this is your baby moving! First-time parents often notice it later (18-22 weeks).
Anatomy Scan
The most detailed ultrasound of your pregnancy checks all organs, limbs, and placenta position. This is when you can often learn your baby's sex!
Halfway There!
You're at the midpoint! Baby is about 10 inches long. Your uterus reaches your belly button level.
Viability Milestone
At 24 weeks, babies born prematurely have a chance of survival with intensive medical care. This is a significant milestone.
Glucose Tolerance Test
A test for gestational diabetes. You'll drink a glucose solution and have blood drawn to measure how your body processes sugar.
Explore by Week
Second Trimester Symptoms
Growing Baby Bump
Your bump becomes clearly visible. Wear it proudly — maternity clothes become necessary around week 14-16.
Round Ligament Pain
Sharp pains in your lower abdomen as the uterus stretches. Usually brief and harmless. Call your doctor if severe.
Back Pain
As your center of gravity shifts, back pain becomes common. Pregnancy-safe exercise and proper posture help.
Leg Cramps
Especially at night. Stay hydrated, stretch your calves before bed, and consider magnesium (ask your doctor).
Nasal Congestion
Increased blood flow to mucous membranes causes pregnancy rhinitis. A humidifier and saline spray help.
Vivid Dreams
Heightened emotions and hormones often cause vivid, sometimes strange dreams. Completely normal!
Skin Changes
Linea nigra (dark line down the belly), chloasma (pregnancy mask), and stretch marks may appear.
Heartburn & Indigestion
Your growing uterus pushes up on your stomach. Eat smaller meals and avoid lying down after eating.
Second Trimester To-Do List
Clinical Context for the Second Trimester
The second trimester runs from week 13 through the end of week 27. For most women, this is the most comfortable stretch of pregnancy — morning sickness typically resolves, energy returns, and the higher-risk window of the first trimester has passed. Routine prenatal visits are usually every 4 weeks during this period.
The anatomy ultrasound(a.k.a. the "20-week scan") is performed between 18 and 22 weeks per ACOG Practice Bulletin No. 175. It evaluates fetal anatomy in detail — brain, heart, spine, kidneys, limbs, placental position — and is the primary opportunity to detect structural anomalies. Sex determination is usually possible at this point if the family wants to know. A repeat scan is ordered if anatomy can't be fully visualized.
Quickening— the first time you feel fetal movement — typically happens between 16 and 22 weeks for first pregnancies, often earlier for subsequent pregnancies (14-18 weeks). Movements feel like flutters, bubbles, or popcorn at first. Daily kick counts aren't routinely recommended until 28 weeks, but pay attention to your baby's pattern.
Gestational diabetes screeningis performed between 24 and 28 weeks per ACOG Practice Bulletin No. 190. The standard approach is a 1-hour 50g glucose challenge; an elevated result triggers a confirmatory 3-hour 100g glucose tolerance test. Women with risk factors (BMI ≥30, prior GDM, family history of diabetes, certain ethnicities) may be screened earlier. Diagnosis is followed by dietary counseling and home glucose monitoring, with insulin or metformin added if targets aren't met.
Tdap vaccination is recommended in every pregnancy between 27 and 36 weeks (CDC), with week 27 as the earliest typical timing to maximize maternal antibody transfer to the newborn. Flu vaccine (inactivated only — never live attenuated) is recommended any time during the season. Both are safe and evidence-based.
When to call your provider in the second trimester:vaginal bleeding, leaking fluid, severe headaches with vision changes (possible preeclampsia warning), painful uterine contractions, decreased fetal movement after you've started feeling regular kicks, or signs of preterm labor before week 37 (regular contractions, low back pain, pelvic pressure, fluid leak).
📚Clinical Sources & References
The calculations and guidance on this page are based on current clinical standards and peer-reviewed research. Reviewed by Samantha L. Fox, RN, BSN, MSN — Emergency Department nurse and US Navy Nurse Corps officer.
- [1]ACOG Practice Bulletin No. 175: Ultrasound in Pregnancy. Obstet Gynecol. 2016;128(6):e241-e256.
- [2]ACOG Practice Bulletin No. 226: Screening for Fetal Chromosomal Abnormalities. Obstet Gynecol. 2020;136(4):e48-e69.
- [3]ACOG Committee Opinion No. 804: Physical Activity and Exercise During Pregnancy and the Postpartum Period. Obstet Gynecol. 2020;135(4):e178-e188.
- [4]ACOG Practice Bulletin No. 190: Gestational Diabetes Mellitus. Obstet Gynecol. 2018;131(2):e49-e64.
- [5]CDC. Vaccines During Pregnancy. Centers for Disease Control and Prevention. Updated 2024.