16 Weeks Pregnant: Baby Development, Symptoms and Tips
Short Answer: At 16 weeks pregnant, your baby is about 11 to 12 cm long, roughly the size of an avocado, and weighs around 100 grams. The skeleton is hardening, the ears are developing, the eyes can sense light and the baby moves constantly, though first-time mothers rarely feel it yet. You are in the middle of the second trimester, and most people feel well, with a visible bump and good energy. This is the best week for the quad screen blood test, and you should book your anomaly scan for 18 to 22 weeks. In Bangladesh, protect yourself from mosquito bites, because dengue in pregnancy is serious, and call a doctor for any fever, heavy bleeding, severe pain or fluid leaking.
Pregnancy weeks are counted from the first day of your last period, not from conception. Sixteen weeks pregnant means about fourteen weeks since conception. You are in your fourth month with about 24 weeks to go. For the week before, read our guide to 15 weeks pregnant, for the next, 17 weeks pregnant, and to follow the whole journey see our pregnancy guidelines week by week.
Week 16 at a glance
| Detail | At 16 weeks |
|---|---|
| Trimester | Second |
| Months | About 4 |
| Baby’s length | About 11 to 12 cm (4.5 inches) |
| Baby’s weight | About 100 grams |
| Heart rate | About 120 to 160 beats per minute |
| Weeks to go | About 24 |
| Size comparison | An avocado |
Your baby at 16 weeks
Growth. Your baby has roughly doubled in weight since week 14. The growth now is mostly in length and weight, and over the next month your baby will gain several times this weight.
Head and face. The head is held more upright, and the neck is longer. The face is more expressive, with muscle movements such as frowning, squinting and grimacing. These are reflexes, not feelings, but you may see them on a scan. The eyes face forward, and although the eyelids are closed, your baby can sense bright light through them. The ears have moved into their final position.
Hearing. The tiny bones in the ear are hardening, and the hearing nerves are linking to the brain. Your baby may start to respond to loud noises and low sounds, such as your voice and heartbeat, in the coming weeks. Talking and singing to your baby is a nice habit, even if the effect on development is not proven.
Bones and muscles. The skeleton is changing from soft cartilage to bone, and the skull and long bones show up well on ultrasound. The muscles are stronger, and your baby can kick, stretch, roll and flex the fingers.
Skin and hair. The skin is thin and see-through, with blood vessels visible underneath. Fine hair called lanugo covers the body. Eyebrows and the first hairs on the scalp are growing. Fingerprints and toe prints have formed.
Digestion and organs. The gut is working, and your baby swallows amniotic fluid. The first sticky, dark waste, called meconium, builds up in the bowel. It is passed after birth. The kidneys make urine, which adds to the amniotic fluid. The liver and pancreas are working.
Genitals. The external genitals are now well formed, and a clear scan may show the sex. The anomaly scan at 18 to 22 weeks is the usual time to find out, if you want to know. The position of the baby and the quality of the image can affect what the sonographer sees.
Movement. Your baby is active, with kicks, hiccups, turns and thumb-sucking. Some people who have been pregnant before feel movement now, like bubbles, flutters or a gentle tap. First-time mothers usually feel the first movement between 18 and 22 weeks. A placenta at the front of the womb, called an anterior placenta, can mute the feeling for a while. Do not worry if you feel nothing yet.
Your body at 16 weeks
Womb. Your womb is about the size of a large grapefruit, and the top sits roughly halfway between the pubic bone and the navel. A bump is likely to be visible, especially if you have had a baby before. For first-time mothers, the bump may still be small. Your height, build and muscle tone all affect how you show.
Energy. Many people feel at their best now, with less nausea, better sleep and a stronger appetite. Use the energy for gentle exercise and planning, but do not overdo it.
Appetite. You need about 300 extra calories a day in the second trimester, the equivalent of a banana, a glass of milk and a handful of nuts. You do not need to eat for two.
Blood volume. Your body is making more blood, so you may feel warmer, sweat more and get dizzy when you stand up fast.
Skin and hair. A glow is common, but so are acne, dry skin and dark patches on the face (melasma). A dark line down the belly (linea nigra) may appear. Hair often looks thicker. These changes usually fade after the birth.
Breasts. They are larger and heavier, and the areolas may darken. A supportive, wire-free cotton bra helps.
Memory. Forgetfulness, sometimes called “pregnancy brain”, is common. Lists and phone reminders help.
Common symptoms and what helps
| Symptom | Why it happens | What helps |
|---|---|---|
| Backache | Growing womb, loosening joints, posture | Flat supportive shoes, good posture, side-sleeping with a pillow, gentle stretches |
| Round ligament pain, a sharp pull in the lower belly or groin | Ligaments stretch as the womb grows | Move slowly, rest, warm bath |
| Stuffy nose, nosebleeds | More blood flow to the nose lining | Saline spray, a humidifier, lean forward and pinch the nose for a bleed |
| Bleeding gums | More blood flow to the gums | Soft brush, gentle flossing, dental check |
| Headaches | Hormones, tiredness, dehydration | Rest, fluids, ask your doctor before taking medicine |
| Dizziness | Blood pressure changes, low blood sugar | Eat regularly, stand up slowly |
| Heartburn | Relaxed valve at the top of the stomach | Smaller meals, avoid spicy and oily food, stay upright after eating |
| Constipation | Slow gut, iron tablets | Fibre, water, daily movement |
| Leg cramps, mostly at night | Circulation and mineral changes | Calf stretches before bed, drink water, ask about calcium |
| Increased vaginal discharge | Hormones | Cotton underwear, no douching |
| Itchy, stretching belly skin | Skin stretching | Moisturiser, loose cotton clothes |
| Swollen feet and ankles | Fluid retention | Raise your feet, avoid long standing |
| Skin darkening | Hormones | Sunscreen and a hat |
Do not take any medicine, including painkillers and herbal products, without asking a doctor or pharmacist. Use pregnancy-safe skincare, and avoid retinoids such as retinol and tretinoin.
When to call a doctor
| Usually normal | Call a doctor soon |
|---|---|
| Short, sharp pulls in the lower belly | Severe or constant abdominal pain |
| Mild cramps after activity that settle with rest | Bleeding that soaks a pad in an hour, or with clots |
| Milky white discharge | Watery fluid leaking, or foul, itchy or coloured discharge |
| Occasional headache | Severe headache with blurred vision or sudden swelling |
| Tiredness, mood swings | Fainting, chest pain or trouble breathing |
| Mild swelling of feet late in the day | Sudden swelling of the face and hands |
| Occasional nosebleed | Any fever, burning urination or pain in one calf |
Call straight away for fluid leaking from the vagina, regular tightening of the belly that does not stop, or any fever. If you feel sad, anxious or hopeless for more than two weeks, tell your doctor. If you ever have thoughts of harming yourself, seek help right away.
Tests this week
| Test | When | What it does |
|---|---|---|
| Quad screen (blood test) | About 15 to 22 weeks, best at 16 to 18 | Estimates the chance of Down syndrome, Edwards syndrome and neural tube defects |
| Amniocentesis | From 15 to 16 weeks | Diagnostic test if screening shows a higher chance |
| Anomaly scan | 18 to 22 weeks | Checks organs, growth, placenta and often the sex |
| Glucose test | 24 to 28 weeks | Screens for gestational diabetes |
| Anti-D injection | About 28 weeks, if you are Rh negative | Protects future pregnancies |
| Tetanus-diphtheria vaccine | During pregnancy, as your doctor advises | Protects you and your baby |
The quad screen. It measures four substances in your blood. The result, with your age and weight, gives a chance, not a diagnosis. A low chance is reassuring but is not a guarantee. A higher chance means you can talk to your doctor about amniocentesis, which gives a firm answer but carries a small risk of miscarriage. Most people with a higher chance result still have a healthy baby.
The anomaly scan. It is the detailed scan that checks the baby’s organs, spine, limbs, face, heart and the position of the placenta. Book it now, because slots fill up. The scan is usually 20 to 40 minutes.
Other checks. Ask your doctor about your hemoglobin, blood sugar, blood pressure and urine at each visit. Ask about thalassemia screening and the influenza vaccine, which is recommended in pregnancy in many countries. If you are Rh negative, ask about anti-D.
Staying safe in Bangladesh
Dengue and mosquito bites. Dengue spreads through mosquito bites, and it is a real risk in Bangladesh, especially during and after the monsoon. Dengue in pregnancy can be serious for both mother and baby. Remove standing water from pots, buckets and tyres around your home. Use a mosquito net, screens and a pregnancy-safe repellent, and wear long sleeves. See a doctor straight away if you have a fever, severe headache, pain behind the eyes, body pain, rash or bleeding gums. Do not take ibuprofen or aspirin for fever unless your doctor says so. Ask your doctor which medicine and dose is safe for you.
Heat and fluids. Hot and humid weather can dehydrate you and cause dizziness. Drink water through the day, wear loose cotton clothes, avoid long hours in direct sun and rest in the shade. Oral rehydration salts help if you have diarrhoea or vomiting.
Food and water safety. Drink boiled or filtered water, wash fruit and vegetables, cook food all the way through and avoid street food from places where hygiene is uncertain. Stomach infections can dehydrate you quickly.
Fasting. If you plan to fast during Ramadan or for other reasons, talk to your doctor first. Many doctors advise against fasting in pregnancy, or recommend close monitoring.
Travel and roads. Wear a seat belt, with the lap strap below the belly and the shoulder strap across the chest. Avoid long, bumpy journeys when you can.
Food and supplements
Eat more of:
- Protein: eggs, well-cooked fish, chicken, lentils (dal), beans and milk
- Iron-rich foods: leafy greens (shak), lean meat and lentils, with lemon or guava for vitamin C
- Fruit and vegetables: a variety of colours every day
- Whole grains and fibre: brown rice, whole wheat roti and oats
- Calcium: milk, yogurt and small fish eaten with the bones
- Water: about 8 to 10 glasses across the day
Take as advised: iron-folic acid tablets, calcium and vitamin D as your doctor prescribes. Many doctors start iron around now, and calcium from about 20 weeks. Do not add extra supplements on your own. Take iron away from tea and milk, and with something sour such as lemon.
Limit: caffeine to about 200 mg a day, which is one or two cups of tea or a single small coffee, and sugary and fried snacks.
Avoid: alcohol, all tobacco (including zarda and jorda), raw or undercooked meat, fish and eggs, unpasteurized milk and cheese, unwashed produce, large predatory fish such as shark and swordfish, high-dose vitamin A and herbal tonics your doctor has not approved.
Weight gain. From now, a person of normal weight usually gains about 0.4 to 0.5 kg a week. Total gain over the whole pregnancy depends on your weight before pregnancy, and Asian-specific BMI ranges may apply, so ask your doctor.
| Weight before pregnancy | Recommended total gain |
|---|---|
| Underweight | 12.5 to 18 kg |
| Normal weight | 11.5 to 16 kg |
| Overweight | 7 to 11.5 kg |
| Obese | 5 to 9 kg |
Exercise and sleep
Move. The standard advice for healthy pregnancies is about 150 minutes of moderate activity a week, such as 30 minutes of brisk walking on most days. Swimming, prenatal yoga, stationary cycling and pelvic floor exercises are good choices. You should be able to talk while you exercise. Avoid contact sports, heavy lifting and anything with a risk of falls. Stop and call your doctor if you have pain, bleeding, dizziness or trouble breathing.
Pelvic floor. Squeeze and lift the muscles you use to stop urine flow, hold for a few seconds and release. Do a few sets a day.
Sleep. Sleep on your side, with a pillow between your knees and another under your belly. After about 20 weeks, doctors advise against sleeping flat on your back. Keep a regular bedtime and avoid screens at night.
Planning ahead
The second trimester is the easiest time to get organised.
- Maternity leave. Under Bangladesh’s labour law, working mothers in the private sector are entitled to 16 weeks of paid maternity leave, eight before and eight after the birth. Government employees receive six months. Check your own contract.
- Place of birth. Decide where you want to give birth and visit the hospital or clinic. Ask what the package includes and what an emergency would cost.
- Money. Start a simple budget for prenatal care, delivery and baby costs.
- Prenatal classes. Ask your doctor about classes for birth, breathing and breastfeeding.
- Dental care. Dental treatment is safe, and this trimester is the best time for it.
- Clothes. Buy a few comfortable maternity clothes, a supportive bra and flat shoes. You do not need a full wardrobe.
- Your partner. Talk about birth plans, names and parenting, and share the load at home.
Checklist for this week
- Book your anomaly scan for 18 to 22 weeks
- Ask about the quad screen and other screening, and the costs
- Take iron-folic acid and any supplements your doctor prescribes
- Ask about calcium, thalassemia screening, the tetanus-diphtheria vaccine and the flu vaccine
- Check your home for standing water and set up mosquito protection
- Keep a list of your medicines and share it with your doctor
- Cut caffeine, alcohol and tobacco
- Start a daily walk and pelvic floor exercises
- Book a dental check
- Save your doctor’s number and the nearest hospital’s emergency number
FAQ
How big is the baby at 16 weeks?
About 11 to 12 cm long and 100 grams, roughly the size of an avocado. Sizes vary a little between babies.
Can I feel the baby move at 16 weeks?
Some people who have been pregnant before do. Most first-time mothers feel the first movement between 18 and 22 weeks. Do not worry if you feel nothing yet.
Can I find out the baby’s sex at 16 weeks?
Sometimes a clear scan can show it, but the anomaly scan at 18 to 22 weeks is more reliable.
Should I have a bump at 16 weeks?
Many people do, especially after a first pregnancy. First-time mothers may still look only slightly rounder. Both are normal.
What is the quad screen?
A blood test done at about 15 to 22 weeks that estimates the chance of Down syndrome, Edwards syndrome and neural tube defects. It is a screening test, not a diagnosis.
Is dengue dangerous in pregnancy?
It can be. Dengue in pregnancy can lead to complications for both mother and baby. See a doctor straight away for any fever, and protect yourself from mosquito bites.
Is it safe to exercise at 16 weeks?
Yes for most healthy pregnancies. Walking, swimming, gentle yoga and pelvic floor exercises are good. Avoid contact sports and heavy lifting.
Can the baby hear at 16 weeks?
The ears are developing, and hearing starts to develop over the coming weeks. Your baby will probably react to loud noises and your voice by around 20 to 25 weeks.
Can I fast during pregnancy?
Talk to your doctor first. Many doctors advise against fasting or recommend close monitoring.
Note: This article gives general information and does not replace advice from your doctor or midwife. Every pregnancy is different. Call your doctor or go to a hospital if you have bleeding, severe pain, fever, fainting or any symptom that worries you.
