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Pregnancy Trimesters by Susan - First Time Mother & Writer


Susan is a writer who has done some work for us over the years, and she became a first time mother in the latter part of 2013, so she has written this feature about what you can expect. Obviously every pregnancy is different, but Susan’s guidelines are very helpful.

First Trimester- 0- 1 3 weeks

Congratulations! The first trimester of your pregnancy is an exciting one as the realisation sinks in that you’re going to have a baby. You may be well into your first trimester before you realise you’re pregnant so it could be a quick few months for you.

You may have told your close family and friends your exciting news, or you may wait to get the pregnancy confirmed with an early pregnancy scan before you spread the word, it’s entirely up to you. From between 6 and 11 weeks, you can get an early pregnancy scan, which will give you a guide as to when to expect your wee one. A later dating scan can also be done between 12 and 17 weeks, checking out your baby and seeing whether you have more than one in there!

This may be something you have been hoping and trying for, or it may be a total surprise, no matter which it is, you will probably feel a range of emotions just now. Be reassured that it is totally normal to feel a bit emotional at this time. It’s a huge change for you and will be exciting but can sometimes feel a bit scary too. There will also be a peak in hormones as your body starts working away creating the little miracle inside you and these hormones can sometimes make you feel a bit overwhelmed. Between 11-14 weeks, you’ll be able to get a nuchal translucency scan. This will just confirm that baby is developing fine and should help to ease any worries you may have.

In the first weeks, your baby is still only the size of a tiny seed but could already be making a huge impact on your life! It can often feel a bit like premenstrual tension in the first trimester. Some people will experience cramping similar to what you might get with a heavy period, you’ll likely get at least some of the mood swings you would get around about the time of your period too.

If you are going to experience morning sickness, it will probably be at its worst in this trimester. You could have anything from mild nausea to frequent vomiting at this time, and unlike the term ‘morning sickness’ it could affect you at any time of the day. Rest assured this is unlikely to last beyond the 12 – 13 week stage, by which time your baby will already be the size of a large lime, and many women are lucky enough to have no sickness at all.

You could feel really tired at any stage throughout your pregnancy, the first trimester being the worst for this. The massive activity going on in your body can sap you of energy so make sure that you’re eating well, taking folic acid and vitamin D supplements and getting lots and lots of rest.

Second trimester: 14-27 weeks

As your second trimester begins, your beautiful baby is about the size of a lemon – he measures around three and half inches from head to bottom.

Any sickness you may have experienced during your first trimester should – hopefully – be coming to and. This should be replaced with a surge in your energy levels. The world will likely be able to see your good news as you begin to show during the early part of this trimester.

A later dating scan, between 12 and 17 weeks, will check the baby’s heart beat – giving you some much needed peace of mind that everything is going well – and confirm that all is as it should be. Around week 18 you may well find yourself feeling a lot hungrier than you had been in recent weeks. Make sure to fill up with good calories – though a few treats never goes a miss – and pick up some maternity clothes to accommodate your new self. The anatomy survey scan, between 18 and 22 weeks, will confirm that your baby is developing properly and has no obvious defects.

Some couples will want to find out what sex their child will be, some won’t. For those that do, this will be an exciting time. The gender scan, available from 19 weeks onwards, will let you decide how best to decorate the new nursery and what clothes to buy as the big day approaches.

At 20 weeks your young one is about the size of an average banana – around six and half inches in length from top to bottom. And you have now reached the mid-way point in your pregnancy; so you’ll put on around a pound a week from now until the big day.

During this stage of your pregnancy, you should be feeling pretty good. The tough times some experience in the early weeks will have abated. One thing to keep an eye on though is your skin. With increased oil production around this time you will be more prone to potentially getting the odd pimple so it is best to cleanse your face two or three times every day.

18 weeks pregnancy scan facial profile Merrion Fetal Health Your growth and well being scan, from 22 weeks onwards, will confirm your wee one is lying in the right position and to check that mother and baby are doing well.

Around 23 weeks you should make sure to take a stroll whenever it is convenient. It is a great way to reduce the swelling you might be experiencing around your ankles. In the last few weeks of your second trimester you will possibly feel some discomfort in your back and also in your legs. The cramp in your legs can be sore so when you feel it beginning, stretch out your calves as this will give you some much needed relief.

You really are not too far away from seeing your new son or daughter for the first time. As the second trimester comes to a close you are only a matter of weeks away from the biggest day of your life. The excitement might just balance out some of those aches and pains.

Third trimester: 28 – 40 weeks

You are now in the third trimester and within touching distance of holding your son or daughter in your arms for the first time. It has been a long six months so far and you have been through a lot but the end is very much in sight.

In the first few weeks of this trimester your baby will be able to open its eyes and react to sounds as its body prepares for the outside world which will soon be the little ones new home.

To build strength for entering into the world your baby will be looking for a good feed during this trimester so make sure you have a nice balanced diet.

As the delivery day fast approaches you may well find it harder and harder to sleep; lying down will seem like a task rather than the relaxing time it used to be. Make sure then to get as much support as possible from your nearest and dearest because you will need to get rest ahead of the big day.

On the flip side though, take some gentle exercise: a relaxed walk around the block or dip in the local swimming pool. Like so many things in life, the best results are achieved through a balanced approach.

Around the mid-way point of this semester your baby will be – on average – around 41cm in length. Mummy will also be continuing to change and develop; while you won’t be getting any taller you will be gaining weight, putting on about 450g a week.

Moving into the latter weeks of this trimester and your due date is very close. At 38 weeks your newborn in waiting is about the size of a leek; excitement and a touch of trepidation are inevitable emotions at this time.

Your baby will be just as active in these last few days. If there is any decrease in activity levels be sure to contact your health provider. It is always important to monitor the progress of your unborn child and this especially true in the final days before your due date.

Forty weeks and your little pumpkin will be well equipped to face the challenges of life on the outside.

Your life is about to change forever, as one unforgettable chapter nears its end a series of new and exciting ones are just days from beginning.

The post dates and liquor scan, done from 40 weeks onwards, will help establish the likely weight of your baby and the location of the placenta.

You have gone through one of the most amazing and unique journeys possible for human beings to experience and you have cared for your unborn child every step of the way by adopting a healthy lifestyle and checking on his or her progress through the different stages of the pregnancy progress.

Congratulations on showing great human strength during this past 40 weeks. You are a credit to yourself and your family. You are ready for the new addition, enjoy every second of it.

Pregnant with diabetes

Fourth trimester: new life begins

Congratulations, you are now in the world of parenthood and are no doubt holding your precious wee one as you read this.

You have gone through three long and complex trimesters of development to reach the special moment when your baby makes its entrance into the world, and a whole new journey of discovery begins.

There are numerous schools of thought on how to manage those first precious months as a mum and you’ll find that everyone has an opinion or a comment to make and a lot of the time you will get totally conflicting advice.

A helpful thing to remember is that your baby is a unique little person who is trying to make sense of the world it has been thrust into. He or she is relying on you to help make the transition from womb to world, as smooth as possible.

Life outside the womb is somewhat of a shock for newborns. Baby is wrenched from the warm, wet, dark, home he or she has been used to for nine months where food is delivered constantly; to a scary new world of noises, bright lights, strong smells and a new nasty experience of hunger.

Your son or daughter is suddenly being poked and prodded by doctors, getting clothed and nappied up when she was quite happily floating about naked before. The unfamiliar sense of hunger must be a horrible one, and never knowing how or if that uncomfortable feeling will get better.

It can be frustrating as a new parent trying to work out what is going through your little one’s mind and often it is simply hunger or a need for a fresh nappy but, for the first few months it can help to remember the massive trauma your baby has been through, as well as the life changing effects on the parents.

The first few months are a time of getting to know each other and trying to ease the stresses of this new world as much as possible. Think about how your baby felt in the womb and try to emulate elements of this wherever possible.

Keep your baby close to you, a sling is great for this. Try to be gradual with exposing your baby to new sights and sounds. Her eyes and ears are only just starting to focus and tune in to her new surroundings. White noise can be soothing for a new baby, vacuum cleaners, hairdryers and washing machines may seem like potentially disturbing noises but they actually remind baby of the soothing humming of the world filtered through water that they are used to. Make sure that your baby doesn’t get hungry or thirsty. It can take a while to adjust to feeding, especially if you are breast feeding, but it is worthwhile to take some time to feed baby on demand so that she knows that she can rely on you to keep her hunger at bay.

The first few months, or fourth trimester, are about trying to ease your baby into its new world as seamlessly as possible. Write off the housework in favour of time spent just feeding and cuddling, follow your instincts, try and imagine what your baby must be feeling, show them love at every opportunity and the rest will work itself out.


All articles on the blog and website are intended as information only. Please do not consider any of the information provided here as a substitute for medical advice. At all times seek medical advice directly with your own doctor and medical team.


Nuchal Translucency

12-14 weeks


Anatomy Survey

21-22 weeks


Later Dating

10-17 weeks


Gender Scan

19 weeks onwards


Growth & Well Being

22 weeks onwards


Post Dates & Liquor

40 weeks onwards


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