Week 16 of Pregnancy: Your Baby Is the Size of an Avocado

This article is for informational purposes only and is not medical advice. Always consult your healthcare provider with questions about your pregnancy.

TL;DR

Your baby is about 11.6 cm — the size of an avocado.
Facial expressions are becoming more defined.
You might feel the first tiny flutters of movement (quickening).
Gender can potentially be determined via ultrasound this week.

Your Baby This Week

Your baby is now the size of an avocado — about 11.6 cm — and facial expressions are becoming part of the daily routine. The muscles in your baby's face are developing enough to allow squinting, frowning, and even what looks like smiling, though these expressions are reflexive rather than emotional at this stage.

The nervous system is rapidly maturing, connecting the brain to muscles throughout the body. This means your baby's movements are becoming more coordinated. Instead of random jerks and twitches, you might see on an ultrasound your baby deliberately reaching, grasping, and even sucking a thumb.

Your baby's eyes are moving slowly beneath closed lids, and the ears are close enough to their final position that your baby may start responding to sound soon. The heart is now pumping about 25 quarts of blood per day — a number that will increase to around 300 quarts by the end of pregnancy.

Tiny toenails are forming, and the legs are now longer than the arms. If you're having a girl, millions of eggs are forming in her ovaries this week. The circulatory system and urinary tract are fully functioning.

Your Body This Week

This is the week many parents have been waiting for — you might feel the first flutters of baby movement. Called "quickening," these early movements feel nothing like the kicks you'll experience later. Most people describe them as tiny bubbles popping, a light fluttering, or even the sensation of popcorn popping deep in your belly.

If this is your first pregnancy, you might not recognize quickening until closer to weeks 18-22. If you've been pregnant before, you may notice it earlier because you know what to look for. Either way, don't worry if you haven't felt anything yet — it doesn't mean anything is wrong.

Your uterus is about the size of a small melon now, and your belly is likely showing enough that people who know you're pregnant can see the bump. You might be solidly in maternity clothes territory or finding creative ways to extend your regular wardrobe.

Some people experience a "pregnancy glow" around this time — the combination of increased blood volume and oil production can give skin a flushed, dewy look. Of course, that same oil production can also mean breakouts, so the "glow" is a bit of a mixed bag.

Common Questions at Week 16

What does quickening feel like?

Quickening feels different for everyone. Common descriptions include bubbles, butterflies, light tapping, or a "goldfish swimming" sensation. It's often so subtle that you might mistake it for gas at first.

When is the anatomy scan?

The anatomy scan (also called a level 2 ultrasound) typically happens between weeks 18-22. This detailed ultrasound checks your baby's organs, bones, and growth, and can reveal the sex if you want to know.

Is it normal to have more vaginal discharge?

Yes. Increased clear or white discharge (called leukorrhea) is normal during pregnancy due to higher estrogen levels and increased blood flow. Talk to your provider if it's green, yellow, foul-smelling, or accompanied by itching.

Can I find out the gender now?

Potentially, yes. By week 16, an experienced ultrasound technician may be able to determine the sex, though many providers wait until the anatomy scan at 18-22 weeks for a more reliable look. Non-invasive prenatal testing (NIPT) done earlier can also reveal sex with high accuracy.

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This Week's Tip

You might feel the first tiny flutters of movement this week, called quickening. These early sensations are easy to miss — they're gentle and irregular. Try lying still on your back or side after a meal or a cold drink. Movement is often more noticeable when you're relaxed and paying attention. If you don't feel anything yet, that's perfectly normal. Your baby is still small, and there's plenty of cushioning between those little limbs and your belly wall.

Milestone: Gender Can Be Determined

If you choose to find out, the sex of your baby may be determinable around week 16. Some parents are eager to know, while others prefer to wait or skip finding out entirely. There's no right or wrong approach — it's completely your call. If you already had NIPT testing, you may already know. Otherwise, the anatomy scan in a few weeks will give your provider a clear look.

Sources

American College of Obstetricians and Gynecologists (ACOG). How Your Fetus Grows During Pregnancy.
Mayo Clinic. Fetal Development: The 2nd Trimester.