4 months pregnant: belly, symptoms and baby development

4 months pregnant with avocado for scale

by Lorna White |
Updated on

At 4 months pregnant you're in the second trimester of pregnancy and are about to experience some exciting milestones, such as your bump popping out and more baby movements.

Now in month four, you're 13 to 16 weeks pregnant and luckily your nausea and pregnancy heartburn should begin to calm down as your little foetus grows.

The four-month stage is usually when your bump begins to pop and you will really start to look pregnant. As your belly begins to grow, new symptoms will start to appear as those not so pleasant early pregnancy symptoms disappear. We spoke with Midwife Marley on the typical stages of baby development and side effects and symptoms of being four months pregnant.

4 months pregnant symptoms

At 4 months pregnant a few of your earlier symptoms will start to ease and a few new symptoms will start to appear.

Here are some common symptoms at 4 months pregnant:

Haemorrhoids - while most common in the third trimester, you may experience piles in pregnancy from 4 months pregnant onwards. Haemorrhoids are an unfortunate side effect of pregnancy that many mums-to-be experience. Make sure you're eating enough fibre like wholemeal bread, fruit and vegetables to ease any constipation. If you're struggling you should ask your midwife or doctor to recommend a cream to use to ease the pain. Don't use a cream before consulting your doctor or midwife first.

Sensitive gums or teeth - Some women get swollen and sore gums, which may bleed, during pregnancy. Bleeding gums are caused by a build-up of plaque on the teeth. Hormonal changes during pregnancy can make your gums more vulnerable to plaque, leading to inflammation and bleeding, so it's important to keep on top of looking after your teeth.

You can get free Dental checks during your pregnancy, so it could be worth having a few check ups.

Varicose veins - usually starting in the second trimester, these can get worse as you near delivery. This is because the increased pressure of the uterus on the pelvic veins disrupts blood flow to the leg veins in pregnant women. It can be uncomfortable, so put your feet up when you can and try some gentle exercises too.

Pregnancy food cravings - this is one symptom that might continue past the first trimester into the second. It's okay to give into those pregnancy cravings every now and then, as long as for the most part you're eating a varied diet. If however, you begin to crave things like coal or rocks, it could be a sign of iron deficiency, so it's a good idea to speak to your doctor or midwife.

Boost in energy - since common pregnancy symptoms such as morning sickness and heartburn start to decrease, many people experience a boost of energy as they enter the second trimester. Take advantage of this and try to be more active, it will help you feel even more energised.

Increased sex drive - thanks to your pregnancy hormones, many women experience an increased libido late in the first trimester and in the second. Along with this increased libido comes increased vaginal lubrication and a hypersensitive clitoris due to extra genital blood flow. So, take advantage of it! And don't worry, it won't hurt the baby.

Abdominal pains – temporary bouts of stomach pain aren't usually anything to worry about at this time of your pregnancy as your bump begins to grow and your body changes to support baby's growth. Often felt one side of your lower abdomen, this pain can also be a result of constipation or trapped wind. It is however important to call your midwife or doctor if you have stomach pain that lasts longer than half an hour, especially if it's accompanied by vaginal bleeding or spotting.

Stretch marks – As your body changes and your skin stretches, you may start to notice thin stretch marks on your stomach or on your breasts. Depending on your skin tone, these marks may be brown, pink or purple in colour. These can sometimes feel itchy too. The advice is to stay hydrated and use a gentle moisturiser or body oil to keep your skin hydrated.

Nasal congestion – The hormonal changes you experience during pregnancy can sometimes result in the blood vessels in your nose to swell which can give you the sensation of a blocked or runny nose. If this begins to bother you, you may want to talk to your doctor or midwife about things you can take to help this.

Your baby's development at 4 months pregnant

Your little foetus can now move their facial muscles plus have reached a few other developmental milestones such as:

1) Baby can hear you - By the fourth month, their ears are working and your little one will be able to hear muted sounds, your heartbeat and the sound of your voice. It's a good time to start reading to them, singing to them and also have little conversations so they really get to know your voice.

2) Sensitive to light - Babies reaching the four-month mark will also become sensitive to light at this point. It's likely they'll be able to see bright lights outside your bump, especially on sunny days.

3) Identifying the sex - Their genitals are now fully developed and their external genitals will soon be visible so it's likely you'll be able to find out the sex (if you wish to) very soon, as you enter the fifth month of pregnancy.

4) Finger prints - Your baby now has their very own fingerprints, and, if you looked at your baby's skin at four months it would look wrinkled.

5) Baby's face – Their little facial muscles can now begin to move, although their expressions are still random. And although their eyes are still shut, they can sense light and their ears are also working

Belly and bump during 4 months pregnant

From the end of month 4, between 16-20 weeks, your body will start showing your baby's growth, but don't worry if you haven't noticed much of a change since you were three months pregnant. It's important to remember that every pregnancy is different, so for some women, their bump may not be noticeable until the end of the second trimester and even into the third trimester.

How big is my baby at 4 months?

At the start of the fourth month, your baby is around the size of a lemon, measuring around 8.5 centimetres, crown to rump. As you get to the end of the month, baby has now grown to the size of a avocado, measuring about 14 centimetres from crown to rump and weighing around 190 grams.

What does my baby look like at 4 months?

Your baby is growing nicely at 4 months and here's a little glimpse as to what they look like in the womb at the start of the month.

week-16

Midwife Marley's top tips for when you're 4 months pregnant

Start thinking about antenatal classes

It’s good to be informed about what to expect and to help prepare for a positive birth experience. Most couples will book onto these in their last trimester but it’s good to start looking around now as some do get booked quick!

Make sure you've informed your employer

If you are working and have told your employer you are pregnant, ensure they carry out a risk assessment on you as soon as possible. This will ensure any adaptations or changes you may need at work can be made. Your employer may ask you for a MATB1 maternity certificate but your doctor or midwife can’t sign it until you are at least 20 weeks pregnant so let your employer know that.

Check in with your midwife

You should have an appointment with your midwife at around 16 weeks. This is usually just to check on how you are and to go over your blood results. Write down any questions you want to ask as you probably won’t see her for a while. If you are a first-time mother, your next appointment won't be until 25 weeks and 28 weeks if you have had a baby before!

Pregnancy is thirsty work

You may find that you become more thirsty as your pregnancy progresses and your baby grows. It’s recommended by the WHO to drink around 3 litres of water per day when you are pregnant. That’s 6 x 500 ml bottles in a 24 hour period.

Try and set aside some ‘me’ time each day if you can. Time to read a book, have a bubble bath or even go for a short walk are all good ways that help your body to relax and release ‘feel good’ hormones that will have a positive effect on you and your baby.

4 months pregnant checklist

Think about baby names

Surely one of the best things about bringing a little person into the world is that you get to give it a totally awesome baby name - or a tidy, traditional one, whichever you prefer. But who knew it was so complicated?

You think of a name and then remember that person at school who was called the same and it’s a goner, another one is struck off because your third cousin removed called her baby that, the next suggestion meets with a grimace from your mother so that one’s gone, and then nobody can pronounce the next one on the list.

Decide where to give birth

There are plenty of options to decide from when considering where to give birth these days so it's a good idea to have a look into what could work for you. Whether you fancy a home birth or you're not sure which hospital to go for, have a chat with your doctor or midwife to get their expert opinions.

Start browsing maternity clothes

It won't be long until your clothes feel on the snug side and you might want to start looking at maternity clothes to fit you and your growing bump.

Thinking about a babymoon?

With your new boost of energy, now is a great time to have your babymoon as you're still safe to fly. There are so many places you could spend your final getaway as a two with your partner.

Maternity exemption certificate

Now is a good time to ask your doctor or midwife about applying for a maternity exemption certificate - this will allow you to claim free dental care and prescriptions while you are pregnant.

About the expert

This article contains expert advice from Midwife Marley Hall, a registered and practicing Midwife with five children herself (including a set of twins). Midwife Marley has practiced midwifery in various settings throughout London and Surrey over the past 10 years covering both the NHS and private sectors, and is an expert in all things antenatal, pregnancy and postnatal care for women and is also a hypnobirthing instructor.

Lorna White is the Senior Digital Writer for Mother&Baby. After running the Yours magazine website, specialising in content about caring for kids and grandchildren, Lorna brought her expertise to Mother&Baby in 2020. She has a keen interest in a range of topics from potty training and nutrition to baby names and early development and has a wide range of experienced medical experts and professionals at her fingertips. In her spare time, she enjoys spending time with her two young sisters, dog walking and enjoying the outdoors with her family.

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