What to Expect in Your Second Trimester, A Complete Guide
Weeks 13 to 27 covered in full, for expectant parents in Bexley, Erith, Dartford and surrounding areas
For many people, the second trimester is when pregnancy starts to feel good.
The relentless nausea of the first trimester tends to ease. The bone-deep exhaustion begins to lift. The bump starts to show, properly, visibly, in a way that feels exciting rather than just uncomfortable. And somewhere in the middle of this trimester, something happens that changes everything: you feel your baby move for the first time.
Weeks 13 to 27 are often called the "golden trimester," and for many expectant parents that's exactly what they are. But the second trimester also brings its own set of changes, milestones, tests, and things to think about and understanding what's coming helps you enjoy these weeks to the fullest.
This guide covers everything you need to know.
What Is the Second Trimester?
The second trimester runs from week 13 to week 27 of pregnancy. By the time you reach week 13, your baby is fully formed, all the major organs, limbs, and features are present and the focus of development shifts from formation to growth and maturation.
The risk of miscarriage drops significantly after the first trimester, which is why many people feel more comfortable sharing their pregnancy news as they enter these middle weeks.
Your Baby's Development Week by Week
Weeks 13–16, Growing Fast
By week 13 your baby is around 7cm long and weighs approximately 23 grams. The head, which has been disproportionately large throughout early development, is now more in line with the rest of the body. Your baby's facial muscles are developing and they can grimace, squint, and make sucking movements.
By week 14 the thyroid gland is producing hormones. Lanugo, a fine, downy hair that covers the body and helps regulate temperature, is beginning to grow. The digestive system is practising its movements, and your baby is beginning to swallow amniotic fluid.
By week 16 your baby is around 11cm long. Their eyes can detect light even though the eyelids are still fused shut. They are making breathing movements, drawing amniotic fluid in and out of the lungs in preparation for breathing air after birth. Fingerprints are forming, each one unique.
Weeks 17–20, Quickening
This is the period when most parents feel their baby move for the first time, an experience known as quickening. First-time parents typically notice movement between 18 and 22 weeks; those who have been pregnant before may feel it earlier, from around 16 weeks, as they know what to look for.
Early fetal movements are often described as flutters, bubbles, or a gentle rolling sensation, easy to mistake for wind in the early days. Over time they become unmistakable.
By week 18 your baby is around 14cm long and covered in vernix, and the white waxy coating that protects the skin. The ears are now in their final position and your baby can hear sounds, including your voice, your heartbeat, and sounds from outside the womb. Talking, reading, and playing music to your bump from this point onwards is not just sentimental, your baby is genuinely hearing it.
By week 20 your baby is around 25cm from head to toe, and this this is when measurements shift from crown-rump to full length. This is also the week of your anomaly scan.
Weeks 21–24, Becoming More Baby-Like
Your baby's movements are becoming stronger and more coordinated. They have sleep and wake cycles, though these may not align with yours, which is why many babies are most active at night. They are beginning to develop taste buds, and research suggests they respond differently to different flavours in the amniotic fluid based on what you eat.
By week 24, viability, and the point at which a baby born prematurely has a chance of survival with specialist neonatal care, is generally considered to begin. A baby born at 24 weeks would require intensive support, but survival is possible. This is an important legal and medical threshold in the UK.
Weeks 25–27, Preparing for the Third Trimester
By week 25 your baby is around 35cm long and weighs approximately 660 grams. The brain is developing rapidly, forming the characteristic folds and grooves of a mature brain. The lungs are beginning to produce surfactant, and the substance that will allow them to inflate and work properly after birth.
Your baby's eyes are beginning to open. Their skin is less translucent and more opaque as fat deposits build up. They may respond to loud sounds with a startled movement.
By the end of week 27, the final week of the second trimester, and your your baby weighs around 900 grams and is approximately 37cm long. In just fifteen weeks they will be ready to be born.
Second Trimester Symptoms, What's Normal
Energy Returns
For most people, the exhaustion of the first trimester eases significantly as the second trimester begins. The placenta has taken over hormone production from the corpus luteum, hormone levels stabilise, and many women describe feeling like themselves again. Make the most of this energy, it's a great time to prepare for the birth, complete your antenatal course, and do anything physical that will be harder in the third trimester.
Nausea Eases
For the majority of pregnant women, nausea improves significantly by weeks 12 to 14. For some it disappears entirely; for others it lingers into the second trimester, particularly in the mornings or when tired. If you're still experiencing significant nausea beyond week 14, mention it to your midwife.
Growing Bump
The bump becomes clearly visible during the second trimester, usually from around 14 to 20 weeks for first-time parents, sometimes earlier in subsequent pregnancies. As your uterus rises out of the pelvis and into the abdomen you may notice your waistline disappearing and your centre of gravity beginning to shift.
This is also when maternity clothes become genuinely necessary rather than just comfortable. Invest in a few good basics rather than trying to make non-maternity clothes work, and your your changing body deserves to be comfortable.
Round Ligament Pain
The round ligaments support the uterus on either side, and as the uterus grows rapidly in the second trimester, these ligaments can stretch and cause sudden, sharp pains, typically felt low down on one or both sides of the abdomen. Round ligament pain is extremely common, usually brief, and often triggered by sudden movements such as sneezing, coughing, or rolling over quickly in bed.
It is not dangerous, but if you experience abdominal pain that is persistent, severe, or accompanied by bleeding or contractions, contact your midwife.
Skin Changes
Pregnancy hormones can have significant effects on the skin during the second trimester:
The linea nigra, a dark vertical line that appears down the centre of the abdomen, is caused by increased melanin production and is completely harmless. It usually fades after birth.
Stretch marks may begin to appear as the skin stretches to accommodate the growing bump, particularly on the abdomen, breasts, hips, and thighs. There is no product proven to prevent them, though keeping the skin well moisturised can help with any associated itching and dryness.
Chloasma or the "mask of pregnancy", patches of darker pigmentation on the face, can develop due to increased melanin. Sun protection helps prevent them from darkening further. They usually fade after birth.
Skin glow, many people notice their skin looking better in the second trimester. This is partly due to increased blood volume giving the skin a healthier appearance, and partly due to pregnancy hormones.
Itching, mild itching, particularly over the stretching bump, is normal. However, if you experience severe or generalised itching, particularly on the palms of the hands or soles of the feet, or itching that is worse at night, contact your midwife. This can occasionally be a sign of a liver condition called obstetric cholestasis, which requires monitoring.
Hair and Nail Changes
Many women notice that their hair becomes thicker and shinier during pregnancy. This is because the hormonal changes of pregnancy cause hair that would normally shed to stay in place, you lose less hair than usual. This effect reverses after birth, which is why many women experience significant hair loss in the months following delivery. It's normal and temporary.
Nails may also grow faster and become stronger, though some people find they become more brittle.
Nasal Congestion
Increased blood flow and oestrogen levels can cause the mucous membranes of the nose to swell, leading to nasal congestion and nosebleeds. This is called pregnancy rhinitis and is completely harmless, if annoying. Steam inhalation, saline nasal sprays, and a humidifier can help. Avoid decongestant nasal sprays unless your GP or pharmacist has confirmed they are safe in pregnancy.
Heartburn and Indigestion
Heartburn may begin or worsen in the second trimester as the growing uterus pushes upward against the stomach. Eating smaller, more frequent meals, avoiding lying down immediately after eating, and propping yourself up with extra pillows at night all help. Gaviscon and certain antacids are safe in pregnancy, check with your pharmacist.
Leg Cramps
Painful muscle cramps, typically in the calves, are common in the second and third trimesters, often striking at night. The exact cause isn't fully understood, though dehydration and low magnesium are thought to play a role. Staying well hydrated, stretching the calf muscles regularly, and flexing the foot upward (rather than pointing the toes) when a cramp strikes can help.
Varicose Veins
Increased blood volume and pressure from the growing uterus can cause varicose veins to develop or worsen, typically in the legs but also sometimes in the vulva (vulval varicosities). Support tights, keeping active, elevating the legs when resting, and avoiding standing for long periods all help manage symptoms.
Back and Pelvic Pain
As the bump grows and posture adapts, back pain becomes increasingly common in the second trimester. Pelvic girdle pain (PGP), pain in the pelvis, hips, and groin, can also begin in the second trimester, often worsening as pregnancy progresses.
Neither back pain nor PGP is something you have to simply endure. Osteopathic treatment, physiotherapy, and pelvic support belts can all provide significant relief. We recommend Bexley Osteopathic Clinic, a specialist clinic with nearly four decades of experience in pregnancy care, for expert musculoskeletal support throughout pregnancy. They also offer pregnancy massage and acupuncture, which can complement osteopathic treatment beautifully in the second trimester.
Warning Signs in the Second Trimester
Contact your midwife or maternity unit promptly if you experience:
Vaginal bleeding, any significant bleeding should be assessed. Light spotting after intercourse can be normal due to cervical sensitivity, but fresh red bleeding warrants prompt contact.
Severe or persistent abdominal pain, different from normal round ligament pain, which is brief and position-related.
Signs of preterm labour, regular tightening or contractions, particularly if accompanied by lower back pain, pelvic pressure, or a change in vaginal discharge, before 37 weeks. From 24 weeks, call your maternity unit if you experience these symptoms.
Reduced fetal movement, once you have established a sense of your baby's normal movement pattern (typically from around 24 weeks), trust it. If movement reduces or stops, contact your maternity unit.
Severe itching, particularly on the palms and soles, or itching that is worse at night, as mentioned above.
Symptoms of pre-eclampsia, severe headache, visual disturbances, sudden severe swelling, or pain below the right ribs. Pre-eclampsia can develop from around 20 weeks.
Your Second Trimester Appointments and Scans
Midwife Appointments
In a straightforward pregnancy, you'll typically have midwife appointments at weeks 16 and 25 during the second trimester. At each appointment your blood pressure will be checked, your urine tested, and from around 20–24 weeks your midwife will begin measuring your fundal height (the distance from the pubic bone to the top of the uterus) to track your baby's growth.
The 20-Week Anomaly Scan
The most significant appointment of the second trimester is the anomaly scan, offered between 18 and 21 weeks. This is a detailed structural check of your baby from head to toe, looking at the brain, spine, heart, abdomen, kidneys, limbs, and face. The sonographer is specifically screening for eleven serious conditions as part of the NHS Fetal Anomaly Screening Programme.
The position of the placenta is also checked, a low-lying placenta (placenta praevia) at this stage will need a follow-up scan later in pregnancy to check whether it has moved.
If you would like to know the sex of your baby, this is usually possible at the anomaly scan, mention it to the sonographer at the start of the appointment. Bear in mind that it isn't always possible to tell, depending on your baby's position.
For a more detailed overview of your scans, including private scan options in the local area, see our dedicated ultrasound blog.
Blood Tests
At your 16-week appointment you may receive the results of the first trimester screening blood tests. Around 28 weeks, which falls at the very start of the third trimester, you'll be offered further blood tests including a full blood count to check for anaemia.
If you have risk factors for gestational diabetes, you'll be offered a glucose tolerance test (GTT), usually between 24 and 28 weeks. This involves a fasting blood test, drinking a glucose drink, and a second blood test two hours later.
Second Trimester Practical To-Do List
Tell your employer. You must inform your employer of your pregnancy no later than 15 weeks before your due date (around 25 weeks of pregnancy). Most people tell their employer before this, but the second trimester is when many people feel comfortable doing so. Once informed, your employer must carry out a risk assessment of your role.
Research your maternity leave options. Work out when you want your maternity leave to start, what you'll be entitled to, and how the finances will work. Our blog on preparing for your baby covers maternity and paternity leave in detail, including links to the relevant GOV.UK calculators.
Book your antenatal course. The second trimester is the ideal time to book your antenatal course. Most courses run in the third trimester and fill up quickly, booking from around 20 weeks ensures you get the dates you want. We run courses from our base in Erith, serving families across Bexley, Dartford, Sidcup, Belvedere, and the wider Southeast London and Kent area. View our upcoming dates here.
Start thinking about your birth preferences. You don't need a completed birth plan yet, but the second trimester is a good time to start exploring your options, where you want to give birth, what pain relief you might want, what matters most to you. Our blog on writing a birth plan covers everything you need to know.
Think about infant feeding. Whether you're planning to breastfeed, formula feed, or haven't decided yet, the second trimester is a good time to start gathering information. Attend a breastfeeding workshop if your area offers one, and know that your midwife and health visitor are available to support you after the birth whatever you decide.
Set up your sleeping arrangements. Think about where your baby will sleep. The safest sleep environment for a baby is on their back, in their own separate sleep space (cot, moses basket, or bedside crib), in the same room as you for at least the first six months. The Lullaby Trust has excellent, up-to-date safe sleep guidance.
Look after your body. The second trimester is a good time to seek osteopathic treatment or pregnancy massage if you're experiencing back or pelvic pain, addressing it early leads to better outcomes than waiting until the third trimester when it's more established.
Enjoy it. The second trimester genuinely is a golden period for many people. Your bump is showing. You can feel your baby move. The nausea has (hopefully) eased. You have energy. You're not yet at the heavy, uncomfortable stage of late pregnancy. This is the time to do the things you want to do, go for the dinner, take the weekend away, have the date nights, see the people you love.
Feeling Your Baby Move, What You Need to Know
Feeling your baby move for the first time is one of the most profound experiences of pregnancy. Those early flutters, tentative, uncertain, easily missed, gradually give way to unmistakable kicks, rolls, and nudges that feel increasingly like communication.
Once you reach 24 weeks, monitoring your baby's movements becomes important. You don't need to count kicks, what matters is knowing your baby's individual pattern and noticing if that pattern changes.
Every baby has their own movement pattern. Some babies are very active; others are quieter. What matters is what is normal for your baby. From around 24 weeks, start paying attention to when your baby tends to be most active and what their movements typically feel like.
Movements should not reduce as you approach your due date. This is a common myth, in fact, movements should remain consistent throughout the third trimester. A baby does not run out of room to move.
If you notice a reduction in movement, contact your maternity unit. Don't wait until the next day. Don't eat something sweet and lie down and hope the movements return. Call your midwife or maternity unit immediately. They will never think you are wasting their time, and this this is exactly the kind of concern they want to hear about promptly.
The charity Kicks Count has excellent resources on monitoring fetal movement. kickscount.org.uk
From Little Village Antenatal
The second trimester is when pregnancy starts to feel real in the most wonderful way and it's the perfect time to start thinking seriously about how you're going to prepare for the birth and the weeks that follow.
At Little Village Antenatal, our comprehensive antenatal courses are designed for exactly this moment, when you're feeling well enough to engage, informed enough to ask the right questions, and ready to start building the knowledge and community that will carry you through labour and early parenthood.
We're based in Erith, serving families across Bexley, Dartford, Sidcup, Belvedere, and the wider Southeast London and Kent area. We're FEDANT registered (National Register Entry Number: 13969), and our courses cover birth preparation, infant feeding, infant first aid, and the postnatal period, with partners included throughout.
View our upcoming course dates and book your place here.
The second trimester is the time to lay the foundations. Let us help you build them.
This blog is for informational purposes only and is not a substitute for advice from your midwife, GP, or healthcare team. If you have any concerns about your health or your baby's wellbeing during pregnancy, always seek medical advice promptly. In an emergency, call 999.