Month 4: Welcome to the Second Trimester
Weeks 14–17 of Pregnancy
Month 4 marks the start of the second trimester, often the most enjoyable phase of pregnancy.
Welcome to the second trimester, often called the honeymoon phase of pregnancy. Many women find this to be the most enjoyable part of their pregnancy journey. Morning sickness typically fades, energy returns, and you will start to show that beautiful baby bump. This month brings exciting developments as your baby's movements become more coordinated.
What is happening this month
The second trimester brings a welcome relief from many first-trimester symptoms. Your risk of miscarriage has dropped significantly, and you may feel more comfortable sharing your news widely. Your baby is growing rapidly, and you might even want to find out whether you are having a boy or girl at your upcoming scan.
Week-by-week development
Baby can squint, frown, and grimace. The liver produces bile, and the spleen helps produce red blood cells.
Your baby is forming taste buds and can sense light through closed eyelids. The hair pattern on the scalp is forming.
Baby's movements are more coordinated. The circulatory system is fully functional. You might feel the first flutters.
Baby's skeleton is changing from soft cartilage to bone. Sweat glands begin developing. Fat stores start forming.
Your baby's development
By the end of month 4, your baby has grown to about the size of an avocado (10–12cm) and weighs approximately 100–140 grams. The rapid development continues:
- Facial muscles are developing and your baby can make expressions
- Eyes are moving into their final position, though still closed
- Ears are nearly in their final position and your baby may hear your voice
- Arms and legs are more proportionate to the body
- Bones are hardening, especially the backbone
- The nervous system is starting to function
- Fine hair known as lanugo begins covering the body for warmth
- External genitals are formed enough to potentially determine sex
- Baby is practising breathing movements with amniotic fluid
Size comparison
Your baby is about the size of an avocado
10–12 cm (4–5 inches)Changes in your body
The fourth month often brings the pregnancy glow as increased blood flow gives your skin a radiant appearance. Your body is adjusting beautifully to pregnancy, and many women feel their best during this time:
Energy Boost
Most women experience renewed energy and vitality
Visible Bump
Your pregnancy becomes more obvious as your bump grows
Pregnancy Glow
Increased blood flow creates that famous radiant appearance
Increased Appetite
With nausea gone, your appetite likely returns with enthusiasm
Skin Changes
Possible darkening of nipples, freckles, and appearance of the linea nigra
Nasal Congestion
Increased blood flow can cause stuffiness and occasional nosebleeds
Important care tips
Healthy weight gain
Now that appetite has returned, focus on nutritious foods. Average weight gain is about 450–680g per week in the second trimester. Choose nutrient-dense foods rather than empty calories. You only need about 340 extra calories per day during this trimester.
Stay active
With increased energy, this is a great time to establish or maintain an exercise routine. Walking, swimming, antenatal yoga, and light strength training are excellent choices. Aim for 30 minutes of moderate activity most days of the week, but always listen to your body and consult your healthcare provider.
Anomaly scan preparation
Your detailed anomaly scan typically happens around 18–21 weeks to check your baby's development and anatomy. If you are planning to find out your baby's sex, this is usually when it can be reliably determined. Some private clinics offer earlier gender scans from 16 weeks. Decide together whether you want to know or keep it a surprise.
Maternity wardrobe
Your regular clothes are likely feeling tight now. Invest in comfortable maternity basics such as stretchy leggings, supportive bras, and tops that will grow with you. Do not forget comfortable, supportive shoes as your centre of gravity shifts and feet may swell slightly.
When to contact your midwife, maternity unit or call 999
If you experience any of the following, contact your midwife or go directly to your nearest maternity assessment unit. In an emergency, call 999.
- Vaginal bleeding or fluid leakage
- Severe abdominal pain or regular contractions
- Severe headaches or vision changes
- Rapid weight gain with swelling of face and hands
- Signs of urinary tract infection
- Persistent vomiting or inability to keep fluids down
Looking ahead
Month 5 brings even more exciting developments. Many first-time mothers feel their baby's movements for the first time, known as quickening, between weeks 18–20. You will also have your detailed anomaly scan, where you will see incredible images of your baby and ensure everything is developing normally. This is also an ideal time to start thinking about antenatal classes and birth preferences. Enjoy this special time - the second trimester truly is a wonderful phase of pregnancy.
Frequently asked questions
Month 4 marks the beginning of the second trimester, often called the honeymoon phase. Morning sickness typically subsides, energy returns, and the baby grows to the size of an avocado with coordinated movements and developing facial expressions.
The pregnancy glow refers to the radiant appearance many women develop in the second trimester due to increased blood flow and circulation. This enhanced circulation gives the skin a healthy, luminous look.
By 16 weeks, external genitals are typically developed enough to determine gender via ultrasound, though some practices prefer to wait until the 18–20 week anomaly scan for more reliable results.
The second trimester is called the honeymoon phase because most uncomfortable first trimester symptoms such as morning sickness fade, energy levels increase, and the risk of miscarriage drops significantly, while the bump is not yet large enough to cause discomfort.
During the second trimester, healthy weight gain is typically 450–680g per week. Focus on nutrient-dense foods and aim for about 340 extra calories per day during this trimester.
Month 4 is typically when regular clothes start feeling tight and many women transition to maternity wear. Invest in comfortable basics such as stretchy leggings, supportive bras, and tops that will accommodate your growing bump.
Walking, swimming, antenatal yoga, and light strength training are excellent choices. Aim for 30 minutes of moderate activity most days, but always listen to your body and consult your healthcare provider before starting any new exercise routine.
The detailed anomaly scan is typically scheduled between 18–21 weeks to check your baby's development and anatomy. This is when gender can be reliably determined if you choose to find out.
