• Penni from Up Up n Away

Pregnancy : 2nd Trimester

Updated: Feb 5


pregnancy second trimester development changes baby hospital

Week 13


You


Congratulations you have now entered your second trimester! The second trimester is often considered to be the best period of pregnancy. You will probably find that many of the side effects of the first trimester have begun to disappear and you should begin to experience a general feeling of contentment and well-being. Also, you do not yet have the full weight of a maturing baby placing stress on your body. Below are some key events that will occur during your 2nd trimester:

  • Announcing your pregnancy

  • Physical Changes - what is happening to you and your Baby

  • Baby Hiccups and Movement

  • Emotional changes - memory, mood, depression/elation, protective, concerns are you glowing, are you freaking out, fears of birth Libido and Sex Drive

  • Dressing for Pregnancy

  • Weight Gain

  • Complications

  • Pregnancy side effects – the weird and the wonderful

  • Predicting baby’s sex *Old wives’ tales for a bit of fun? *

  • Choosing a birth location and support services and staff - Home birth or Hospital.

The second trimester is often considered to be the best period of pregnancy. You will probably find that many of the side effects of the first trimester have begun to disappear and you should begin to experience a general feeling of contentment and well-being. Also, you do not yet have the full weight of a maturing baby placing stress on your body.

Your baby


The first three months from conception were a period of rapid development, and the following three will represent a stage of rapid growth for your baby.

Baby’s head is still whopping and large in comparison to her growing body, but her nose and chin are now well-defined and bones like the ribs are forming. From this point on, baby’s body starts growing to catch up with that big head, and baby is likely to be around 7cm to 9cm and will enjoy sloshing around in 100mls or so of amniotic fluid.


Your baby can move in a jerky fashion, flexing the arms and kicking the legs. In fact, if you prod your abdomen, your baby will squirm in response, although you will not be able to feel it just yet.


Her skin is paper-thin and rather see-through, and if you could see her inside you, you could even get a glimpse through her skin of her functioning and still-developing organs.

Baby’s sense of taste and smell are more developed, and her amniotic sac will continue to increase in size and mass and fill with more fluid. Baby had better enjoy all that space she is got right now for somersaults and movement because in another few months it will get squishy!


Week 14


You


One third of your pregnancy journey is completed. By now, pregnancy hormones are levelling off. This means less nausea, less frequent urination and less exhaustion. What a relief! However, you may be experiencing some constipation since those darned hormones have relaxed your bowel muscles causing them to work slower and less efficiently. Your uterus is also pressing on your bowel. Be sure to increase the fibre in your diet if constipation becomes a problem.

Maternity clothes may be a "must" by now. Some women try to get by for a while by not buttoning or zipping their pants all the way or by using rubber bands or safety pins to increase the size of their waistbands. Others wear their partner's clothing, but that usually works for only a short time. You are going to get even bigger. You will enjoy your pregnancy more and feel better with clothing that fits comfortably and provides you room to grow.

How your body responds to this growth is influenced by any previous pregnancies and the changes your body experienced then. Your skin and muscles stretched to accommodate your uterus, placenta and baby, and that changed them permanently. Skin and muscles may give way faster to accommodate your growing uterus and baby. This means you may show sooner and feel bigger.

Your baby


Baby is now 8 to 9.3cm long and has nearly doubled his weight since last week to 43 grams. By this week, your baby's ears have moved from the neck to the sides of the head. Eyes have been moving gradually from the side of the head to the front of the face. The neck continues to get longer, and the chin no longer rests on the chest.


Lanugo, the fine, short hairs that help keep the body heat inside your baby, will form now and grow to cover his entire body. Baby's skin is very thin, and fat will not develop for several weeks, so he needs extra help in staying warm. The lanugo will cover your baby for several months and will not be shed until there is enough fat to keep him warm. When the fat is thick under the skin, the lanugo will fall off and end up in the baby's intestines as meconium, which is what comes out as his first dirty nappy!


Your baby's placenta is now fully functional but remains larger than the baby (until about 16 weeks). The placenta supplies your baby with oxygen, fats, proteins, vitamins and minerals as well as removing carbon dioxide and waste materials, by filtering them through the placental tissues attached to the uterus. This intricate process of diffusion makes these exchanges possible because the tiny blood vessels of mother and baby are incredibly close together, yet remarkably always separate. The placenta is not a barrier, as once thought. It allows most substances in the mother's blood stream to cross over into the baby's blood stream. These include alcohol, nicotine, caffeine, natural remedies, medications, drugs and viruses, possibly affecting the baby's growth and development (depending on what stage the pregnancy is at).

Week 15

You


This will be an overly exciting week for you! When you visit the doctor or midwife, there is a particularly good chance they will be able to pick up your baby's heartbeat with a doppler. The doppler determines the rate of your baby's heartbeat. If the doctor or midwife cannot pick up your baby's heartbeat yet, do not fret. It is still very early in your pregnancy and you probably will be able to hear it in the next week or two.


If you are having trouble sleeping trying to drink a glass of warm milk or having a warm bath before bed. Do not run the water too hot as it is not healthy to raise your temperature above 37.8°C while pregnant as it increases your heart rate, reduces blood flow to the foetus, and potentially puts the baby under stress.


You may also like to try new sleeping positions to help you sleep comfortably during your pregnancy. Do not lie on your back when you sleep. As your uterus gets bigger, lying on your back can place the uterus on top of important blood vessels (the aorta and the inferior vena cava) that run down the back of your abdomen. This can decrease circulation to your baby and parts of your body. Some pregnant women also find it harder to breathe when lying on their back. Lying on your stomach puts extra pressure on your growing uterus. This is another reason to learn to sleep on your side. For some women, their favourite thing after delivery is to be able to sleep on their stomach again.

After your first consultation, pregnancy visits are scheduled at regular intervals. However, their frequency until 28 weeks can vary, depending on your individual needs and your caregiver's preferences.

In the past, pregnancy visits during the 2nd trimester were routinely scheduled every 4 weeks. However, recent research has shown that antenatal visits every 5 to 6 weeks are acceptable for women whose pregnancies are progressing normally.

Your baby


Baby is now 10.1cm long from crown to rump and weighs 50-70 grams. By the end of this week, all the major organs will be formed within your baby. The heart, kidneys, liver, pancreas, lungs and spleen will be in their proper locations, but not necessarily performing their function yet. The organs will continue to grow and develop with each respective system and begin working over the next couple of months. In no time, all his little systems will be up and running.


It is still a little early to feel movement, although you should feel your baby move in the next few weeks! Your baby's rapid growth continues. Its skin is thin. At this point in its development, you can see blood vessels through the skin. Fine hair, called lanugo hair, covers the baby's body. By this time, your baby may be sucking his thumb, which you may well pick up during an ultrasound. Eyes continue to move to the front of the face but are still widely separated. Ears continue to develop externally and bones that have already formed are getting harder and retaining calcium (ossifying) rapidly. If an x-ray were done at this time, the baby's skeleton would be visible.


Week 16

You


As your baby grows, your uterus and placenta are also growing. Six weeks ago, your uterus weighed about 140g. Today, it weighs about 250g. The amount of amniotic fluid around the baby is also increasing. There is now about 250ml of fluid. You can easily feel your uterus about 7.6cm below your belly button.


Can you feel butterflies fluttering in your stomach this week? That is a great sign! The feeling is called quickening; it is when you first feel the movements of your baby. It may feel like gas, an upset tummy or like butterflies floating around in your stomach, but it really is baby on the move. Quickening starts from week 16 but becomes more pronounced by week 18 to week 20. You may find it easier to feel those early fluttery movements if you lie down. The distinctive kicks and punches are still a few weeks away and that is most likely when your partner will be able to feel baby's movements, too.

Your baby


He/she is about 11.6cm long, weighs 100 grams and has enough muscle strength and coordination for her to form a fist. Her fist is small and tightly clenched and fine details are beginning to emerge. The creases between her fingers, knuckles and palm are beginning to appear. Her nails are starting to grow and the fingerprints that make her completely unique are now programmed in the skin but will not be apparent for several more weeks.


The amniotic fluid around your baby is increasing, allowing them to move freely, floating like an astronaut in space. However, most women cannot feel these movements just yet. Your baby's umbilical cord is now completely mature. Their cord contains two arteries and one vein, enclosed and protected by a thick, gristle-like substance called Wharton's Jelly. This makes the cord slippery and allows it to move freely around your baby and resist compression.

Week 17

You


Around this time your doctor may recommend you have an amniocentesis test if you and your partner's genetic history puts you in a high-risk category or you are over the age of 37. This safe test checks your amniotic fluid for certain chromosomal abnormalities present in your baby such as Down syndrome or hereditary conditions such as Duchenne muscular dystrophy and skeletal dysplasia.


If you have the test you will visit hospital as an outpatient and the whole procedure takes no more than 30 minutes. It begins with a technician performing an ultrasound to locate baby's position, ensuring the technician stays well clear of your baby as he or she uses a needle to extract a small amount of amniotic fluid. The fluid is then sent to a lab and you should have your results within two weeks. A negative result excludes only the condition for which the test was performed. Unfortunately, there is no test to exclude all pregnancy abnormalities.


Your baby


By this week, your baby is about the size of your hand spread open wide and will begin looking more like a baby this week and less like an alien, now he is 13 cm long and weighs 140 grams.


His eyes will have moved to the front of his face and be completely forward looking. His eyelids are still tightly fused shut but his eyes are continuing to form underneath. It will be a few more weeks before his eyelids open, blink or remain open.

Your baby's body is becoming more in proportion to what he will be at birth. Fat begins to form during this week and the weeks that follow. Also called adipose tissue, fat is important to the body's heat production and metabolism. At 17 weeks, water makes up about 89g of your baby's body. In a baby at term, fat makes up about 2.4kg of the total average weight.

Week 18

You


You can feel your uterus below your belly button. If you put your fingers sideways and measure, it is about two finger widths below your belly button. Your uterus is the size of a rock melon or a little larger. Your total weight gain to this point should be 4.5kgs to 5.8 kgs. However, this can vary widely. If you have gained more weight than this, talk to your doctor. Gaining more than the recommended weight can make pregnancy and delivery harder on you. And extra kilos may be hard to lose afterward. Keep watching what you eat. Choose food for the nutrition it provides you and your growing baby.

Does the smell of coffee turn your stomach? When commercials come on the TV, do you want to cover your ears and reach for the volume control? With added hormones in your system, and all the work that your body is doing for your baby, your senses may be in overdrive. Things that do not usually bother you - like sounds, tastes, touches - may drive you crazy right now. Once your baby's growth and development slow, your system will come out of overdrive and your senses will relax and go back to normal.

Your baby


He/she is around 14.2 cm long and 190 grams and her circulatory system has begun to work. Her blood vessels are visible through her thin skin and blood will pump through her veins, arteries, flow through her heart, and all her other major organs. The heart will pump six litres of blood each day! The blood will carry oxygen and nutrients through her body and filter out through the liver. Her ears are now in position and stand out from her head. Blood from your baby flows to the placenta through the umbilical cord. In the placenta, oxygen and nutrients are transported from your blood to the foetal blood. Although the circulation of your blood and that of your baby come close, there is no direct connection.


These circulation systems are completely separate. If you are having a girl, her uterus and Fallopian tubes are formed and in place. If your baby is a boy, his genitals are noticeable. At 18 weeks of gestation, ultrasound can detect some abnormalities of the heart. This can be helpful in identifying some problems, such as Down syndrome. A skilled sonographer looks for specific heart defects. If an abnormality is suspected, further ultrasounds may be ordered to follow a baby's development as pregnancy progresses.

Week 19

You


Your uterus about 1.3cm below your belly button (umbilicus). Your total weight gain at this point should be between 3.6 and 6.3kg. Of this weight, only about 200g is your baby. The placenta weighs about 170g, the amniotic fluid weighs another 320g. The uterus weighs 320g. Your breasts have increased in weight by about 180g. The rest of the weight you have gained is due to increased blood volume and other maternal stores.


You are one week short of the halfway mark and so your body is definitely looking pregnant now. Your shape will begin to show your curves and finding comfortably fitting clothes that you already have may be limiting your wardrobe choices. Investing in maternity clothes is worthwhile because not only will you wear them as you grow in size, you will return to them after baby is born as you drop in size. When you shop for maternity clothes, buy your regular size in maternity. The clothes will be tailored to your shape and dimensions of pregnancy.

Make a list of your favourite baby names. Ask your partner to do the same then swap lists and cross off any names you do not like on each other's list. Hopefully, you will have at least one you both agree on. If not, start again!

Your baby


He/she is about 15.3 cm long and weighs 240 grams. Vernix will begin to coat your baby's beautiful skin. Vernix is a greasy, fat like substance that will cover all the skin on your baby.


The reason for the vernix is two-fold:

1) It provides added insulation on the outside until the fat can build under the skin and regulate his body heat.

2) It protects his skin, which is growing thicker, against being submerged in amniotic fluid 24/7.


Once the vernix is covering his body, the lanugo will begin to fade away. And once the fat is thick under the skin, the vernix will begin to fade and be mostly gone by the time your baby is born.

Week 20

You


Congratulations! You are halfway through your pregnancy at the end of this week. You have seen significant changes in your mood and now you will see big changes in your figure. Your morning sickness should have eased a bit, if it has not disappeared completely. The tiredness you had been feeling should also be going away and your energy levels should be closer to normal. If they are not, make sure to get plenty of rest and eat lots of protein rich foods to boost your energy. This is a great time to discuss with your partner your options for after baby - are you going back to work or staying home?

Pregnancy can be an important time of growing closer to your partner. As you get larger, sexual intercourse may become difficult because of discomfort for you. With some imagination and with different positions (ones in which you are not on your back and your partner is not directly on top of you), you can continue to enjoy sex together during your pregnancy.

Your baby


He/she is about 16.4 cm long and weighs 300 grams measured from her crown to her rump. This week, however, the measurements switch to crown to heel and that makes baby 25.6 cm long. Those little ears on your baby are in fine working order. Your baby can hear sounds, both inside the uterus and on the outside. She will not recognise what they are, however, since she has no way to identify noises. But she will have come to recognise your voice over someone else's. Your baby will also startle when she hears loud or sudden noises from the outside. The internal noises she hears are your heartbeat and growling stomach. It may be possible to hear your baby's heartbeat with a stethoscope at 20 weeks.


Before doctors had doppler equipment that enabled them to hear the heartbeat and ultrasound to see the heart beating, a stethoscope helped the listener hear the baby's heartbeat. This usually occurred after quickening for most women. The sound you hear through a stethoscope may be different than what you are used to hearing at the doctor's office. The sound is not loud.

If you have never listened through a stethoscope, it may be difficult to hear at first. It does get easier as the baby gets larger and sounds become louder. If you cannot hear your baby's heartbeat with a stethoscope, do not worry. It is not always easy for a doctor who does this on a regular basis. If you hear a swishing sound (baby's heartbeat), you have to differentiate it from a beating sound (mother's heartbeat). A baby's heart beats rapidly, usually 120 to 160 beats every minute. Your heartbeat or pulse rate is slower, in the range of 60 to 80 beats a minute. Ask your doctor to help you distinguish the sounds.

Week 21

You


Visiting your doctor or midwife this week could be a lot of fun. Halfway through most pregnancies your doctor or midwife will order an ultrasound as a routine procedure. The ultrasound checks baby's size, organ functions and overall health.


During the ultrasound, the technician can measure specific bones, usually the leg, and tell if your due date is accurate. If the bone measures smaller or larger than normal, they may adjust your due date accordingly.


Before your ultrasound, you will need to drink a lot of water, so your bladder is full during the procedure. The purpose of a full bladder is not to torture you! It is so the technician has an easier time viewing all the parts of your baby.


In addition to your growing uterus, other parts of your body continue to change and grow. You may notice swelling in your lower legs and feet, particularly at the end of the day. If you are on your feet a lot, you may notice less swelling if you are able to get off your feet and rest for a while during the day. 75% of all pregnant women suffer from swollen fingers, ankles and feet. Some women experience pain when various parts of their body swell. If your feet swell, wear pregnancy support stockings to help keep blood from pooling in your feet. You may find swelling gets worse late in the day because of fluid retention.

Your baby


He/she is about 26.7 cm long and weighs 360 grams. The sex of your baby will be distinguishable during this week so you can confidently find out what you are having if you wish. An experienced technician will be able to tell the difference, as long as your baby cooperates. Baby may have his hands between his legs, he may not turn the right way, or just will not move in the right position to get a good view.


Even though the reproduction systems in your baby will be in place, it all remains immature until baby hits puberty and adolescence. The fetal digestive system is functioning in a simple way. By the 11th week of pregnancy, the small intestine begins to contract and relax, which pushes substances through it. The small intestine is capable of passing sugar from inside itself into the baby's body. By 21 weeks of pregnancy, development of the fetal digestive system enables the fetus to swallow amniotic fluid. After swallowing amniotic fluid, the fetus absorbs much of the water in it and passes unabsorbed matter as far as the large bowel.


It is not too early to start thinking about baby names. Sometimes couples have vastly different ideas about names for their child. Do you plan to honor a close friend or relative by using their name? Will you use a family name? What problems could arise if you choose a peculiar, difficult-to-say or hard-to-spell name? What do the initials spell out?

Week 22

You


Your uterus is now about 2cm above your bellybutton and your enlarging abdomen is not too large and does not get in your way much. You are still able to bend over and to sit comfortably. Walking should not be an effort. Morning sickness has probably passed, although some women suffer chronic morning sickness their entire pregnancy, which is called hyperemesis gravidarum.


Are you having short periods of light-headedness? Maybe even feeling a little dizzy when you stand up? These are quite common symptoms during a pregnancy. When you move positions, for instance if you stand up quickly after sitting for a long period, you may be lightheaded. This is because so much of your blood is centered around your uterus and with your growing size, it may not be able to move through your system as quickly as it used to. To prevent this from happening make sure you change positions slowly. You can also sit with your legs propped up to help with circulation, so that when you do stand up, your circulation has a head start.


Iron-deficiency anemia is common during pregnancy. During pregnancy, your baby uses some of the iron stores you have in your body. If you have iron-deficiency anemia, your body does not have enough iron left to make red blood cells because the baby has used some of your iron for its own blood cells.

Your hair may feel a lot thicker than it used to because you shed less hair during pregnancy. To get rid of unwanted hair, you can safely tweeze, wax, and shave, but bleaches or depilatories are not suitable because they can be absorbed into the skin and contain chemicals.

Your baby


He/she is about 27.8cm long and weighs 430 grams. During this week, your baby's skin will make the transformation from being translucent to opaque. No longer will you be able to see everything underneath all that skin. It will become cloudy, but remain red. The skin will appear red until the fat, which is white, builds under the skin layers. Then the skin will turn from red to pink, and then to a very light pink or white if they are Caucasian. The skin will be very wrinkly under the thick coating of vernix, until the fat fills it out and pushes the wrinkles out.

Week 23

You


You may find friends are commenting on your size. They may say you must be carrying twins because you are so large. Or they may say you are too small for how far along you think you are. If these comments concern you, discuss them with your doctor. Do you find your mood swings are worse? Are you still crying easily? Do you wonder if you will ever be in control again? Do not worry. These emotions are typical at this point in your pregnancy. It is generally believed they occur from the hormonal changes that continue through-out pregnancy.

Back pain may be a constant, nagging ache for you right now. Your frame is not used to the added weight, which was put on quickly. With the added weight, your balance and posture will change. Those changes may throw your back out of its normal position, resulting in some minor aches and pains along the way. Ask your doctor before you take any medications to ease the pain. Other ways to ease the pain are to take short breaks through the day so you can get off your feet, wear good support shoes if you are on your feet for long periods and hold a good posture when you walk.

Your baby


He/she is about 28.9 cm long and weighs 501 grams. This week will begin a rapid growth phase for your baby's brain. During this week, and for the next following weeks, billions and billions of brain cells will develop.


These brain cells will control every aspect of your baby - from breathing to circulation, recognising sensory stimulation to movement, and everything in between. The rapid brain growth will also make your baby's head size grow - a little bit. His head will only enlarge by less than two centimetres as the head is the biggest part of baby to emerge from the birth canal.


Week 24


You


You might be able to feel your baby moving from the outside now, by putting your hand on your belly. As your baby gets bigger, you and others will be able to see your baby moving. Towards the very end of your pregnancy, you might even be able to recognise some body parts. Other people might comment on your belly or even touch your belly, even if you haven’t asked them to. It’s OK to tell people not to do this if it makes you uncomfortable – it’s your body.


Blood sugar test for gestational diabetes

You might have this test at 24-28 weeks of pregnancy. If you’ve had a previous pregnancy with gestational diabetes or are at high risk of developing the condition, you’ll probably be offered a test earlier than this. Ask your obstetrician, doctor or midwife for more information.


Planning some help

It’s a good idea to plan practical and emotional ‘back-up’ for after your baby is born. For example, could extended family, friends or other people cook you a meal, drop in for a visit or give you a call? You don’t have to do everything if others are willing to lend a hand.

It’s OK to ask for help too. In fact, some people will appreciate you telling them exactly what you need.


Your Baby

  • Measures about 21 cm in length, and weighs about 630 gm

  • Still looks thin, because the ‘fattening up’ process hasn’t really started

  • Has a layer of fat developing underneath the skin, so the skin is less see-through

  • Likes to move when you’re trying to sleep – this is why you might feel your baby’s movements more at night

  • Might be hiccupping, which might feel like tiny waves of regular movements in your belly – this is completely normal.

Week 25


You

You might be feeling uncomfortable in the rib area, as your uterus expands upwards. You might start getting some indigestion around now. If you haven’t already, consider booking into antenatal classes. Preparing other children

If you have other children, it’s a good idea to prepare them for your new baby’s arrival. What you tell them might depend on the questions they ask, their age and how interested they seem. If you’re planning to have other children at the birth, let your midwife or doctor know. You could also ask them for tips on how to help prepare children for the birth.

Preparing your home

You might already be making changes to your home for your baby’s arrival. Getting your home ready and collecting the things your baby will need can help you and your family feel ready for the birth.

It can be tempting to buy all kinds of stuff. But there are only a few things that your baby absolutely needs. Safety should always be the priority when choosing equipment for babies and baby furniture.

Your baby

  • Is about 22.5 cm long, and weighs about 720 gm

  • Is forming different parts of its spine

  • Might react to a loud noise, or move to the sound of familiar music or voices.

Week 26


You

You might be experiencing backache, Braxton Hicks contractions and vivid dreams. You’ll be gaining weight, and your centre of gravity has shifted. This can sometimes make you feel a bit clumsy as you get used to doing things and lifting things in different ways. The way you walk might change slightly too. Rh type

It’s important to test your blood to find out your Rh type. If you’re Rh-negative, and your baby turns out to be Rh-positive, this can cause serious health problems for your baby. But no-one knows what your baby’s blood type is until after birth. So if you’re Rh-negative, you’ll be offered a special injection called Anti-D at your 26-28 week antenatal visit and your 34-36 week visit.

You’ll also be offered Anti-D if you have a bleed during pregnancy. This reduces the risks of health problems. After your baby is born, blood is collected from your baby’s umbilical cord and the Rh type is checked. You’ll have another Anti-D injection if your baby is Rh-positive. Ask your doctor or midwife for more information.

Some women want only women health professionals to care for them during pregnancy, labour and birth. You can ask for a woman midwife or doctor, but it might not be possible to have one – especially if you or your baby need urgent or specialised medical attention.

Your Baby

  • Measures about 23 cm from head to bottom, and weighs around 820 gm

  • Can hear, see and taste

  • Might move in response if you firmly run your hand over your belly

  • Starts growing a lot of fat and muscle from about now.


raisingchildre.net.au (2020). Second trimester. Retrieved from https://raisingchildren.net.au/pregnancy/week-by-week