16 Weeks Pregnant: Symptoms, Ultrasound and Baby Size


What to expect at 16 weeks pregnant – everything you need to know about your growing baby and bump as you settle into your second trimester

By week 16, you’re settling into your second trimester and, if you had been keeping your pregnancy under wraps, it may prove difficult to hide the news for much longer. Your uterus is now growing at the same rate as your baby, which means a visible bump for many women.

Your baby’s development is also kicking up a gear at 16 weeks. At this point your baby is starting to look more like an actual baby and their eyes will be working and reacting to light.

Read on to find out more about your changing body and growing baby at 16 weeks pregnant.

Think you missed something? Re-visit what to expect at 15 weeks pregnant or head over to our pregnancy week by week guide for more information at every stage of your pregnancy.

How Many Months Pregnant is 16 Weeks?

At week 16 you are in your 4th month of pregnancy and second trimester. You have around 5 months left until your baby is due.

Your Baby at 16 Weeks Pregnant

At 16 weeks pregnant, your baby is developing more and more human-like features and their vital organs and limbs are continuing to form.

By this stage, the foetus has a recognisable face with eyes, eyebrows and even eyelashes. Their eyes are functioning and can react to light, but the eyelids are still closed. The ears are also developing further, and tiny bones are forming meaning your baby may be able to hear your voice.

You may also spot your baby sucking their thumb in upcoming scans after developing the ability to suck at around this stage. Their teeny, tiny facial muscles are also strengthening.  Your baby could be making some adorable facial expressions within the womb.

Meanwhile, your baby’s skin is still translucent. If you could see through your own tummy, into your uterus, you would be able to see baby’s blood vessels.

16 Weeks Pregnant Baby Size

At this stage, the foetus is between 10 to 13 cm tall and weighs about 100 grams. Your baby is approximately the size of an avovcado.


Your Body at 16 Weeks Pregnant

Your body is also going through some big changes. By 16 weeks it may no longer be possible to hide your pregnancy. Your uterus is growing quickly, in order to accomodate your rapidly growing baby. This means your baby bump may start to show more obviously.

16 Weeks Pregnant Symptoms

As well as a protruding belly, there are other signs and symptoms of pregnancy you may experience at 16 weeks pregnant.

Although many of the pesky and unpleasant first trimester symptoms will have subsided by now, look out for the below:

Weight Gain

As your baby and your belly grows, and your pregnancy cravings increase, you might notice you’re putting on weight. Your baby is getting bigger and your should be too, however it is important the weight gain is slow and steady (and you’re mainting a healthy diet). Ideally you should be gaining around 1 pound a week. If you’re experiencing dramatic weight gain or loss during your pregnancy, you should contact your doctor.


With your baby and belly growing, you may experience more aches and pains while adjusting to your heavier weight and bigger frame. Many women will suffer from mild back pain and strained back muscles. It might be time to cash in that offer of a massage from your partner. Or, better still, book in for a professional pregnancy massage.

Bleeding Gums and Nosebleeds

One not so pleasant pregnancy symptom you may experience at 16 weeks is bleeding and swollen gums. This is due to increased blood flow, and fluctuating hormone levels, which can cause increased sensitivity. Nosebleeds are another side effect.

Varicose Veins

The increased blood flow will also cause your veins to become more visible. Although you might not appreciate this aesthetically, it’s a good sign as it means there’s an increased blood supply to your growing baby.

Heartburn and Indigestion

This pesky progesterone has a lot to answer for. Increased levels of the hormone in your body can also cause bloating at 16 weeks pregnant. This is because it slows down the digestion process so that there’s more time to pass the nutrients on to your baby. However, in doing so, your growing uterus will squash and press onto your stomach and intestines. Your hormones also relax the valve between your stomach and esophagus, causing heartburn.


The extra blood pumping around your body can cause you to feel light-headed, dizzy and even faint. To ease these symptoms, try and remember to stand up and sit down slowly and keep sugar levels up with regular (healthy) snacks. If you feel faint, make sure you take a seat and rest up as soon as possible.

Baby Brain

A common symptom many women experience throughout their second and third trimester is something colloquially known as ‘baby brain’ or ‘pregnancy brain’. Forgetfulness is a rite of passage during pregnancy and can be blamed on those annoying hormones and a lack of quality sleep.

Higher energy levels

One positive symptom many women experience as they enter their second trimester is a lease of energy. This is because the placenta begins to kick into action and takes over the job of providing nutrients for your baby.

Increased sex drive

Another plus, with higher energy levels and a new rush of hormones, you may find yourself with increased libido. It’s said your new-found high sex drive can even have health benefits for you and your baby. These include improved mood, better sleep and tightening of your pelvic floor muscles – which can help speed up your recovery after birth. However, doctors advise you should abstain if you have a history of early labour miscarriage.

16 Weeks Pregnant Ultrasound

As you settle in to your second trimester, its time to think about your second prenatal scan. This takes place between 16 to 20 weeks and will be an opportunity for you to have another ultrasound, as well as a number of other tests and measurements.

At this second ultrasound, the doctor, nurse or ultrasound technician will be able to determine the sex of your baby. It’s up to you whether you want to find out!

Your GP or midwife will also carry out a physical examination and order tests such as a urine sample (to check for conditions such as preeclampsia and diabetes), as well as checking your blood pressure. You may also be offered some prenatal vaccines

Read more: Everything you need to know about the harmony test

For more information on development and milestones at every stage of your pregnancy, visit our pregnancy week by week page.

Read more: What is Cranial Osteopathy?

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