Your second trimester: What to expect!

Your second trimester is an incredibly important time in your baby’s development. This is when you're 4-6 months pregnant (that's after the 13 week mark). You might be able to find out your baby’s sex at your scan – which is normally at 20 weeks of pregnancy– if you want to find out, that is.

We've spoken to Andrea Maduro, Senior Medical Advisor at Flo Health, to find out what else you've got to look forward to in your second trimester, from symptoms to the changes in your body and your baby, choices to make and tests to expect.

When does the second trimester start?

Your second trimester of pregnancy is the three months in the middle of your pregnancy. It starts on week 13 and ends after week 27. In terms of symptoms, energy and travel, it can be one of the more enjoyable trimesters as any morning sickness you had in the first trimester should be lessening, you should have more energy than you might have in the third trimester, and if you're planning to head off on holiday, now is a good time to fly.

How many weeks is second trimester?

The second trimester lasts for 14 weeks, from the start of the 13th week to the end of the 27th week. This is roughly the 4th, 5th, and 6th months and is when many women report that their pregnancy starts to feel more real. You'll start to develop a more noticeable bump and are likely to have told your friends and family.

Second trimester symptoms to expect

Hopefully, during your second trimester your morning sickness will come to an end. However, there are plenty more changes happening in your body which could create the following second trimester symptoms:

Growing belly: During the second trimester the bump will start to show. The foetus is getting bigger and putting on weight. But as Andrea Maduro notes, "it’s important to remember, no two bumps are the same. Everyone develops at different paces, and this is totally normal."

Itchy skin: As the bump grows, the skin on the abdomen stretches over time and this might make it itchy. "Itchiness on the body is also pretty common during pregnancy due to the increase in hormones such as oestrogen, progesterone, and prolactin" explain Andrea.

Pigmentation: The skin around the face may get darker. This is called chloasma or melasma. It may last for the duration of the pregnancy before disappearing by itself.

Linea nigra: The linea nigra is a dark line that can form from the upper part of the abdomen down to the pubic area. It’s most common to spot this line on the lower abdominal area.

Back Pain: Lower back pain in pregnancy in the second trimester is caused by your growing bump starting to put pressure on your back. To soothe any aches, try sleeping on your side and maybe invest in a pregnancy pillow.

Round ligament pain: Many pregnant women find they experience round ligament pain which is caused by your ligaments stretching around your belly to accommodate your growing baby. Andrea says "During the second trimester, the uterus grows and as this happens two ligaments that surround the uterus (called round ligaments) and the pelvic muscles loosen and stretch, which can cause spasms and pain. The pain might be on one or both sides of the body. It might last for a few seconds, but some people can experience it for a few hours. And it might feel worse when suddenly moving (for example coughing, sneezing, or laughing).

Stretch marks: That stretching belly may also lead to stretch marks which are a normal part of pregnancy. You could try a stretch mark oil or lotion to soothe itching skin.

Trouble sleeping: Some mums report tiredness in second trimester. As the pregnancy develops, the physical changes to the body can disturb your sleep, leading to tiredness and insomnia in pregnancy.

Dental issues: You might experience bleeding gums, so make an appointment with your dentist.

Varicose Veins: You may also start seeing varicose veins – that is because of the extra blood flowing in your system. This can be helped by having a more active lifestyle and regularly lifting your legs above your heart level.

Leg cramps: Leg pain and cramping in second trimester is pretty common during pregnancy, especially at night. Whether it’s from carrying extra weight or a change in body composition, it isn’t totally clear what causes leg cramps during pregnancy. There are a number of ways to ease pregnancy leg cramps, including yoga, walking and diet changes.

Heartburn: Unfortunately heartburn is one symptom you won't have left behind in the first trimester and which is likely to get worse throughout your pregnancy. "Progesterone levels rise at the beginning of pregnancy and remain high throughout the second trimester. This relaxes the digestive system and slows down how quickly food is processed, which can cause heartburn and constipation" says Andrea.

Constipation: You may have experienced this already but constipation is a possible symptom to look out for, though physical activity and maintaining a good diet can help.

Haemorrhoids: Haemorrhoids or piles are swollen veins in or near the anus which make bowel movements painful. Increased blood volume, and pressure from the growing foetus in the uterus, and constipation can cause haemorrhoids.

There are some danger signs of pregnancy in second trimester to be aware of. The second and third trimesters of your pregnancy are when you're most at risk for pre-eclampsia. Call your midwife or GP for medical advice if you have any of the following which can be symptoms of pre-eclampsia during pregnancy:

• High blood pressure

• Problems with vision

• Severe pain under ribs

• Rapidly increasing swelling of the face, hands or feet

• Strong headache or heartburn that don’t go away with usual medicine

Baby's development in the second trimester:

By the end of the second trimester, your baby will have done some serious growing and developing. They'll grow hair and become able to swallow and hear things around them. They'll even have tiny fingernails and fingerprints.

Growth: At the start of the second trimester your baby is the size of a lemon. By the end of the second trimester they'll be about the size of a head of broccoli!

Internal changes: There are important developments in the nervous system, digestive system and lungs that happen in the second trimester - they start forming red blood cells and kidneys and during week 13, your little one will start developing bones in their arms and legs. The intestines, which up until now have been growing inside the umbilical cord, will move to their permanent spot in your baby’s abdomen.

Downy fur: Your baby’s skin is now covered in hair called lanugo, that keeps them warm until they build more fat in the third trimester.

Eyes will become sensitive to light: By 15 weeks, they will have ears on either side of their head and their eyes are moving from the side of the head to the front of their face. The eyes will start to become sensitive to light, so even though they remain closed, they can now register bright light.

Thumb sucking: Your baby will be starting to make moves that you'll recognise when they arrive - they can suck their thumb, yawn, stretch, and make faces, though they don't really have much control over this. "They start developing the ability to suck, they practice breathing actions, they’re gaining facial expressions and even start opening their eyelids and learn how to blink", explains Andrea.

Heartbeat begins to regulate: Baby's heart is now regulated by the brain, which means it’s not beating so randomly any more, but will still be beating about twice as fast as yours.

Hearing improves: Your baby’s hearing is now getting more acute, which means now is a good time to start talking and singing to your growing bump! In the second trimester, Andrea says "they'll start to hear the mother's voice, heartbeat and some muted sounds from the outside and can start reacting to these noises from outside of the uterus."

Kicking: Baby's arms and legs will now be in proportion, the neurons between the brain and muscles are connected, and the cartilage in your baby’s body will be turning to bone, all of which gives your baby more control over the movement of her limbs - meaning you're much more likely to feel your baby kick. "Remember that all pregnancies are different, and baby's first movements can be felt at any time from 16 weeks up to 24 weeks pregnant" Andrea notes.

Hair growth and features: Your baby is starting to look more like a newborn than ever, with distinct lips, eyelids and eyebrows, and even tiny tooth buds. Their hair is becoming visible and their eyebrows have developed. Your baby's scalp hair pattern also is forming, along with eyelids, eyebrows, eyelashes, and nails and your baby will start to use their facial muscles to smile and grimace. By the end of the second trimester they'll have fully developed genitals.

Hiccups: Your baby might begin hiccupping, causing jerking movements. The blood vessels in their lungs are developing to prepare for breathing in the outside world.

Palms and fingerprints: Your baby’s hands will develop creases in the palms this week (cute!), and soon sweat glands will form in their skin. Your little one will also get fingerprints during the second trimester!

Brain development: Your baby’s brain is really active these days, as more brain tissue is developing. They're an active foetus, sleeping and waking up regularly, opening and closing their eyes and sucking their fingers too.

Choices and decisions during your second trimester

During your second trimester, you're likely to have to make many decisions around work, finding out the gender, or not, and working out a birth plan.

Will you find out the gender? At your 20 week scan you'll have the option to find out the sex of your baby so you might want to have a chat with your partner beforehand to see if you both want to know or would prefer to keep it a surprise.

Birth plan: In addition, while it might seem a long way off, the second trimester is a good time to start thinking about your birth plan. Who do you want as your birth partner? Would you prefer to give birth in a hospital, a midwife led unit or have a home birth? By starting to think through these decisions in the second trimester, you're giving yourself plenty of time to decide.

Work: If you work, you must tell your employer about your pregnancy at least 15 weeks (around month four of pregnancy) before the beginning of the week your baby is due. You will need also need a MAT B1 form.

Childcare: It's not something you'll need to deal with for a while, but some childcare providers have waiting lists so it's worth doing your research now and starting to think about your childcare options if you plan to go back to work.

What appointments and tests can I expect in the second trimester?

There are a few antenatal appointments to keep on top of in the second trimester:

At week 16, you’ll be told about the anomaly scan, which you’ll be offered at 18-20 weeks. The anomaly scan checks the physical development of your baby.

At around 20 weeks you'll have your anomaly scan which is also where you can find out the sex of your baby if you've chosen to. The NHS notes that this scan tests for 11 different conditions and Andrea explains that during the scan a healthcare professional will look for birth defects by examining different physical features:

• Head, face, and neck

• Chest (to ensure the proper heart and lung development)

• Abdomen (to look at the stomach, kidneys, bladder, and umbilical cord)

• Spine

• Arms and legs

At 25 weeks pregnant you may be offered an appointment if this is your first baby. Your midwife will talk about your baby's movements, measure your bump and your blood pressure and test your urine for protein.

Between week 24 and week 28 you'll be offered an oral glucose tolerance test. This test measures the body's response to sugar (glucose), which is the main source of energy. It’s used to check for gestational diabetes, a type of diabetes that develops during pregnancy that raises the risk of certain complications. Andrea tells us, "This test usually happens between 24 and 28 weeks, but if considered high-risk for gestational diabetes (based on an earlier pregnancy, family history, body weight, or medical conditions) screening may be recommended earlier."

Things to do in your second trimester

Go shopping: Your changing body might mean you'll need to do a spot of shopping for some maternity clothes. Depending on the time of year, you might need to invest in a maternity coat as well.

Stay active: Hopefully you have more energy in your second trimester and it's a great idea to try and stay active throughout your pregnancy if possible. There are some brilliant pregnancy exercises you can do without equipment and any are good for both body and mind. Pregnancy yoga is a good one to check out, and you might even end up making mum friends too.

Pelvic Floor Exercises: Oh and don't forget to do your pelvic floor exercises. These will help you through labour and beyond. You might want to think about investing in a pelvic floor trainer.

Bond with your bump: This is an amazing time to bond with your bump as you'll start feeling them moving and reacting to your voice. Make the most of it and encourage your partner to do the same.

About the experts

Andrea Maduro is a Medical Advisor in The Netherlands. She was a Medical Resident in Preventive Child and Youth Healthcare, SBOH, Rotterdam in 2019–2021 and a Medical Doctor in Preventive Child and Youth Healthcare, CJG Rijnmond, Rotterdam in 2014–2019.

A journalist since 2015, Emily Gilbert is the Features & Reviews Editor for Mother&Baby and has written for the website and previously the magazine for seven years. First-time mum to Theodore, Emily writes about everything from the top baby products to pregnancy, fertility and maternal mental health. Specialising in product reviews, Emily is the first to know about all the exciting new releases in the parenting industry.