16 Weeks Pregnant

This week at a glance

Week 16 of pregnancy, at a glance.

Item	Where things stand at 16 weeks
Baby's size	About an avocado (~4.5-5 inches, ~3.5-4 oz)
What's developing	Can hear sounds; reacts to light; facial features and limbs refining
Your symptoms	More energy; possible early flutters; round-ligament twinges; congestion
Coming up	Anatomy (20-week) scan, usually scheduled for 18-22 weeks
Milestone	Quickening possible now for some; often later in a first pregnancy

Baby development at 16 weeks

By 16 weeks the fetus is roughly 4.5 to 5 inches long and weighs around 3.5 to 4 ounces, about the size of an avocado. The body is becoming more proportional as the head growth slows relative to the rest.

The ears are developed enough that the fetus can begin to hear your voice and other sounds, and even with the eyes closed, it can sense and turn away from bright light. Facial features are refined, the limbs and joints move, and the fetus practices small movements throughout the day.

Feeling the first movements

The fetus has been moving since around week 12, but the early flutters of quickening usually become noticeable a little later. If you've been pregnant before, you might sense them around 16 weeks; in a first pregnancy it's common not to feel movement until about 18-20 weeks.

Early movement is easy to miss or mistake for gas or muscle twitches. People describe it as bubbles, flutters, or tiny taps. It tends to be irregular at first and will grow stronger and more frequent in the weeks ahead, there's no need to count kicks yet.

Your second-trimester symptoms

Many people feel noticeably better now: nausea has usually eased and energy often returns, sometimes called the more comfortable stretch of pregnancy. A small bump may be visible, and you might move into looser or maternity clothes.

New, normal changes can include round-ligament twinges as the uterus grows, nasal congestion or occasional nosebleeds, mild swelling, a darkening line down the belly, and tender or fuller breasts. Staying hydrated and moving gently can help with the aches.

What's coming up

• The detailed anatomy scan (often called the 20-week scan) is usually done between 18 and 22 weeks and checks the brain, heart, spine, organs, and growth.
• If you want to know the sex, it can often be seen at the anatomy scan.
• Keep up your prenatal vitamin and routine appointments (about every four weeks at this stage).
• Note any questions for your provider about screening, travel, or symptoms.

Reflects Cleveland Clinic fetal-development and quickening guidance plus ACOG anatomy-scan timing (18-22 weeks), 2024-2026.

Related questions

When will I feel the baby move?

Early flutters (quickening) often start around 16 weeks if you've been pregnant before, and closer to 18-20 weeks in a first pregnancy. The fetus moves earlier than you can feel it. Movement is irregular at first and gets stronger over the following weeks.

Is it normal not to feel movement at 16 weeks?

Yes, very. Many people, especially first-time parents, don't feel movement until 18-20 weeks. The position of the placenta and your body type can also delay when flutters are noticeable. Your provider checks the heartbeat at visits in the meantime.

When is the anatomy scan?

The detailed anatomy ultrasound is typically performed between 18 and 22 weeks. It examines the brain, heart, spine, organs, and growth, checks the placenta and fluid, and can often show the sex if you want to know.

Why do I feel so much better at 16 weeks?

As hormone levels stabilize after the first trimester, nausea usually fades and energy tends to return. Many people find weeks 14-27 the most comfortable stretch. If you still feel unwell, mention it at your next visit, everyone's timeline differs.

Sources & further reading

1. Cleveland Clinic - Fetal Development: Stages of Growth (Week 16)
2. Cleveland Clinic - Quickening in Pregnancy
3. Cleveland Clinic - 20 Week Ultrasound (Anatomy Scan)
4. ACOG - Current Guidance on Prenatal Ultrasound and Screening

This article reflects current AAP, CDC, FDA, and other public-health guidance and is for educational purposes only. It does not constitute medical advice. ParentFlow is a wellness companion — not a substitute for your pediatrician. For any medical concern, contact your healthcare provider.