You’ve hit another milestone at 16 weeks of pregnancy; having endured four months of growing a baby. Although pregnancy is calculated in months and not weeks, you’ve about five months left. Did we answer all your week 15 questions about pregnancy?

By 16 weeks, your bundle of joy is cuter than ever, although its thin body needs fattening up. Vital organs like the heart have been fully functional for weeks now, while others like the liver and pancreas may start working. The growth of different body parts is essential for the continued development of the fetus.

Most 16 week pregnant mothers feel good, but don’t be surprised by the arrival of some pregnancy symptoms and body changes, like your belly “popping” overnight. However, there’s no cause for concern if your pregnant belly’s smaller or bigger than expected – there are countless varieties of bumps worldwide.

What happens next in your pregnancy journey? Find out as we dish regular weekly updates on your growing bump and answer all the unknowns about pregnancy.

Here’s what to expect this week.

At a Glance: Week Sixteen of Pregnancy

• Like nothing better than smashed avo on toast? This week, your baby’s the size of your favourite snack, the avocado, measuring over 12 centimetres.
• They’re also putting on weight. But, at 100-120 grams, they’re as light as a feather (or, more accurately, a wet wipe).
• With long, gangly limbs and little fat, your baby is very lean.
• With your uterus expanding as rapidly as your baby, you might have the start of a bump.
• Breast growth and size might continue into the second trimester after rapidly increasing over the first trimester.
• The second trimester can seem like a dream, but you will experience many symptoms that bring you back to reality. But don’t worry; you’ll cope.

Week Sixteen of Pregnancy Overview

For lack of a better word, your baby bump has “popped”, with your pelvis unable to contain your uterus any longer. It might not be what you pictured (or way bigger than a previous pregnancy), but embrace your belly shape and size, as well as any accompanying body changes.

Two important organs, the pancreas and liver, start working, performing functions vital for fetal growth and development; we explain their roles in the next section. Meanwhile, the baby’s tiny but fully operational heart is beating fast and pumping out litres of blood – stick with us to find out how much!

Building on from the last few weeks, your baby’s enjoying a full range of motility and continues to be active. Can you feel your baby kick yet? You might feel light fetal movements by week 16, which grow stronger as the weeks pass. These movements are called quickening. If you’ve been pregnant before, you’ll know what this feels like, but you might mistake it for a pregnancy-related symptom if you’re a first-time mom. Look out for possible quickening from week 16, but if you miss the moment or don’t experience it, don’t worry; pronounced kicking and punching will come later.

Baby Size And Latest Developments for Week Sixteen of Pregnancy

By 16 weeks, your baby’s the size of an avocado, measuring over 11 centimetres and weighing 100-120 grams. Although still too light, small and fragile to hold in your arms, your 16-week-old fetus is not nearly as tiny as it once was and grows daily.

These are the week 16 developments:

• Two vital organs work hard and perform functions that keep your developing baby alive. One of them is a fully functional pancreas that produces enzymes and insulin that break down food and regulate blood sugar, respectively. The other is an operational liver that produces bile and red and white cells, which are essential for generating oxygen, offering immune support and promoting general health.
• The lungs might still be far from matured fully, but tissue is forming and producing surfactant, a chemical that helps the lungs function post-birth.
• The heart, the most developed organ at this time, continues to beat fast and pumps out nearly 24 litres of blood daily – this amount increases as the baby grows.
• Your baby is responsive to some sounds and has partial hearing. When they’re born, they’ll recognise their mamma’s voice and other noises, like the music you played during pregnancy.
• With so much growing left to achieve, your little one sleeps roughly 12- 14 hours daily.
• Although your baby’s eyes are fused shut, some evidence suggests they detect and perceive light to some extent, with tiny eye motions occurring behind the eyelids.
• At this stage, your baby’s mostly skin, muscle and bones, but their fat will gradually accumulate in the upcoming months.
• Some women experience quickening by week 16, the first fetal movements felt. You might instantly recognise the magical sensation if you’ve been pregnant before. But if you don’t know about quickening, you might confuse little fetal kicks for gas or abdominal cramps.

Because every pregnancy is unique, the above description generalises fetal development. Variations in the timing of milestones can occur.

Body Changes for Week Sixteen of Pregnancy

Sections of the second trimester are comfortable and quite possibly enjoyable, but this stage of pregnancy is not entirely harmonious.

As your baby and uterus grow, symptoms and body changes become unavoidable. The ebbs and troughs of pregnancy hormones will also affect you at different points during pregnancy, even during this honeymoon trimester.

So, what symptoms typically impact women currently? While pregnancies and associated symptoms are unique – you might experience the following.

It’s important to note that all pregnancies are unique. The timing and experiences of pregnancy symptoms may vary.

1. Pregnancy Brain

Are you guilty of leaving your keys in the fridge or confusing butter with soap while pregnant? Welcome to the world of pregnancy brain, a real phenomenon affecting women differently. Whether it’s the occasional brain fart or becomes seriously impairing, pregnancy brain is characterised by forgetfulness and an inability to focus.

You might joke that your brain’s turned off, but the truth is that rising pregnancy hormones can cause dramatic changes in the brain. Higher levels of progesterone and oestrogen can affect areas of the brain related to memory and attention, causing a type of mental fog.

Its impact is felt the worst during the first and third trimesters. However, your brain might feel slightly jumbled by week 16 of pregnancy. The good news is that the changes to your brain aren’t likely to be permanent, although it might take time before you feel back to normal. Give yourself some grace if you and your noggin are not on the same page. Like everything else in pregnancy, the pregnancy brain varies from person to person.

2. Bleeding Gums and Dental Issues

Why do so many women suffer from bleeding, swollen gums and similar dental issues? The primary culprits behind developing dental issues, such as gingivitis, are oestrogen and progesterone. High levels of these hormones cause inflammation and discomfort by increasing blood flow to the gums. Additionally, an environment is created that makes it easier for bacteria, like plaque, to accumulate.

Gingivitis advances into a gum disease called periodontitis if left unchecked and may affect your unborn fetus. Learn to prevent or treat gingivitis in our tips section. Otherwise, read our article for more information on toothache during pregnancy.

3. Aches And Pains

Pain in your groin and both sides of your abdomen are symptoms of round ligament pain. Round ligament pain occurs when the round ligaments – structures that support your womb – stretch under the weight of your growing uterus.

A common symptom of pregnancy, round ligament pain is often felt during the second trimester. Round ligament pain can be triggered by sneezing, laughing and coughing, usually lasting for a few seconds or longer.

Pregnancy pain affects people differently. However, the sensation shouldn’t be intolerable, long-lasting, or accompanied by a fever or chills. Seek out medical advice if you’re concerned about alarming pain or strange symptoms.

Do you feel pain in your back or pelvis? These might also be pregnancy-related. We look at why they occur and pain management for these areas in our week 17 article.

4. Constipation

Pregnancy constipation blocks you up and messes with your bathroom schedule.  That’s because the hormone progesterone relaxes all your muscles, including the ones linked to digestion. This relaxation results in food moving slower through your bowels, leading to your intestines absorbing more water, making your stool hard and difficult to pass.

Week Sixteen of Pregnancy Tips and Tricks

Do you feel good but are starting to notice a few niggling symptoms? Although more tolerable than other trimesters, the second trimester isn’t all peachy. You’ve landed in the right place if you’re looking to tackle symptoms and physical changes that dim your second-trimester joy.

1. Make Lists

Even if you don’t have pregnancy or ‘mom’ brain, there’s a lot you need to do and remember. Write everything down instead of relying upon mental lists that you might forget.

Speaking of lists, have you started jotting down baby names yet? It might seem premature, but it could take a while for you and your partner to agree on a final name.

2. Double Down On Your Oral Hygiene

The likelihood of contracting a gum disease or dental health complication increases during pregnancy, but they can still be prevented.

Prioritise your oral health by brushing your teeth for two to three minutes, flossing daily and using mouthwash to reduce plaque buildup.

Don’t forget the importance of regular dentist check-ups, with visits to your oral health practitioner once every six months or if you can’t remember when you had your last checkup. Remember that in the UK, you are entitled to free NH dentistry throughout pregnancy and up to one year after your baby is born!

3. Embrace Your New Body

It might be difficult for some to appreciate their changing pregnant bodies, and we can understand why. Still, it’s important to recognise that your body is actively building a baby from scratch. Embrace your curves and buy the clothes you love in your new size!

4. Manage Pain

If your back and belly are taking strain under a growing womb, feel better in the following ways:

• Take acetaminophen, an over-the-counter pain medication that’s pregnancy-safe – but check with your doctor first.
• Strengthen your stomach muscles with exercise – yoga and stretching may help to reduce pain.
• Don’t move suddenly, especially when changing from sitting to standing.
• Purchase an ergonomic office chair that supports your back and a pregnancy pillow to promote comfortable sleep.

Do I need an Ultrasound for Week 16 of Pregnancy?

Depending on your circumstances, there’s usually a four-week gap between the first and second ultrasound appointments. If you had an early first ultrasound, your second-trimester scan might be approaching, with most occurring between 18 and 22 weeks.

Curious about what to expect? That’s why we’re here.

A second-trimester ultrasound or anatomy scan provides a detailed view of the womb, where the sonographer checks the health, appearance, position and size of your little one.

You might have genetic screenings or tests booked along with an ultrasound. In our week 15 article, we discussed the different types, why you might need one, what they entail and when they can be done. For example, an elective amniocentesis or an MMS can be performed between weeks 15 and 22.

Fun Facts for Week Sixteen of Pregnancy

• With your fetus constantly moving around, when do they sleep? All the time, actually! They can spend up to 95% of their time asleep, especially during later pregnancy.
• Here’s another interesting fact: did you know that a pregnant woman produces more oestrogen in pregnancy than in her entire life when she’s not pregnant? That’s an incredible amount of hormones, don’t you reckon?

Week Sixteen of Pregnancy Checklist

• Feel for quickening this week – the first fetal movements you’ll feel.
• Have conversations with your little one; your voice soothes them.
• Draw up different lists for various tasks – use apps and digital planners!
• Double down on your oral hygiene.
• Book your second-trimester scan and fetal health tests and screens.
• You might have fetal health tests booked.
• Stay tuned for our week seventeen guide!