Week 21
Your baby is about 25.6 cm (10 in) long and weighs about 300 g (10.5 oz), roughly the length of a banana. That length looks like a big jump from last week, but it is mostly a change in how babies are measured: from this week on, the figures in this book run from crown to heel instead of crown to rump. Babies vary, and so do scan measurements.
Inside, your baby is practising swallowing, and the digestive system is starting to work. For you, the bump is now plain to see, and the skin, veins and fluid balance of your body are all adjusting. This week looks at stretch marks, swelling, a first honest look at money, and ways for your partner to start building their own bond with the baby.
Day 141 · 20 weeks 0 days
Your baby is now measured from head to heel
Until now, your baby has been curled up tightly, and the legs were hard to measure on a scan. So the usual measurement was crown to rump, from the top of the head to the bottom. From around 20 weeks, the legs are long enough to count, and the standard switches to crown to heel. That is why the figure in this week's overview seems to leap ahead by about 10 cm. The real growth is steadier than that. Over the coming weeks your baby will add length slowly and weight more quickly, as fat begins to build up under the skin. The body is also catching up with the head, which has been large for the body since early pregnancy.
At any scan from here on, your care provider may describe size using several measurements: the head, the belly and the thigh bone. Those numbers are combined into an estimate, and estimates can be off by 10 to 15 percent either way. One measurement on the small or large side is rarely a concern on its own. What matters more is how your baby grows over time.
Try this: If you keep a pregnancy journal or photo series, note today's date as the start of the crown-to-heel measurements, so later comparisons make sense.
Day 142 · 20 weeks 1 day
Stretch marks are common and mostly out of your control
As your belly, breasts, hips and thighs grow, you may notice thin lines appearing on the skin. They can be pink, red, purple or dark brown, depending on your skin tone. These are stretch marks, and somewhere between half and nine in ten pregnant people get them.
Stretch marks form when the deeper layer of skin stretches faster than it can adapt. Whether you get them depends mostly on your genes, your skin type and how quickly you gain weight. Younger parents and people whose mothers had them are more likely to get them. No cream, oil or lotion has been shown to prevent them, whatever the label says.
What moisturizing can do is ease the itch and tightness that often come with stretching skin. A plain, unscented cream is enough. Gaining weight steadily rather than in sudden bursts may help a little, and it is good for you anyway.
After birth, most stretch marks fade over months to a paler, silvery colour that is much less noticeable. If they bother you later, there are treatments to discuss with a skin specialist once you are no longer pregnant or breastfeeding.
Try this: After your shower, rub an unscented moisturizer into any itchy skin on your belly and breasts, and notice whether it eases the tight feeling.
Day 143 · 20 weeks 2 days
Your baby is tasting what you eat
Your baby now swallows amniotic fluid throughout the day, sometimes several hundred millilitres in 24 hours. This is practice. It helps the digestive tract grow and teaches the muscles of the mouth and throat how to swallow, a skill your baby will need at the first feed.
The fluid carries small traces of flavours from your diet. Garlic, vanilla, carrot and anise have all been detected in amniotic fluid in studies. Taste buds are formed by now, so your baby may be getting an early sense of the foods your family eats. Some research suggests babies exposed to a flavour before birth are more accepting of it later, though this is not proven to shape lifelong eating habits.
What goes down also comes through. The kidneys filter fluid and your baby passes urine back into the amniotic sac. In the bowel, a thick, dark substance called meconium is slowly forming from swallowed cells, fluid and secretions. It stays put until after birth and becomes your baby's first few dirty diapers.
Try this: Add one colourful vegetable or herb you love to a meal today, and enjoy the thought that your baby is getting a hint of it too.
Day 144 · 20 weeks 3 days
Some swelling in your feet and ankles is normal
Your body is holding more water than usual, and your growing uterus slows the return of blood from your legs. Together, these can cause mild swelling, called edema, in your feet, ankles and lower legs. It tends to be worse at the end of the day, in hot weather and after long periods of standing.
Simple steps help. Put your feet up when you can, ideally above the level of your hips. Move your ankles in circles and flex your feet while you sit. Avoid standing still for long stretches, wear comfortable shoes, and keep drinking water, because cutting back on fluids does not reduce swelling. A walk or a swim can help too.
Swelling that comes on gradually and eases overnight is usually harmless. Swelling that is sudden, or that shows up in the face and hands, can be a sign of a blood pressure condition called pre-eclampsia, which you will read more about later in the book.
Call your care provider if you notice sudden swelling of your face, hands or feet, especially with a headache, blurred vision or pain under your ribs. Get help right away if one calf is swollen, red, warm or painful, as this can be a blood clot.
Try this: Tonight, lie on the sofa or bed with your feet raised on a couple of pillows for 15 minutes.
Day 145 · 20 weeks 4 days
A first honest look at the money
A baby does not have to be expensive in the early months, but some costs are hard to avoid. Diapers, a safe place to sleep, a car seat, clothes and feeding supplies all add up. The bigger change for many families is income: time off work, reduced hours or the cost of child care later on. It helps to look at the numbers now, while you still have time to plan. Start with what you know: your current income, regular bills and savings. Then add what is likely to change, such as a drop in pay during leave, higher grocery or utility bills, and any one-off purchases.
You do not need a perfect spreadsheet. A rough picture is enough to show whether you need to save a little each month from now on, cut a cost, or ask family for help with specific items. Many parents find that borrowed and second-hand clothes and gear cover a large share of the early months. If money worries feel heavy, you are not alone. Social workers, community organizations and some workplaces offer free help with budgets and with finding benefits you may be entitled to.
Try this: Write down your monthly income and essential costs on one page, then circle the three costs most likely to change after the baby arrives.
Day 146 · 20 weeks 5 days
Your partner can start bonding with the baby now
For the person carrying the baby, the connection is physical and constant. For a partner or support person, the baby can feel more abstract, even halfway through. That is common, and it does not mean anything is wrong. Bonding often builds in small, ordinary moments rather than in a single rush of feeling.
Movement is one of the best bridges. Kicks are usually too faint to feel from outside at first, but from around now, a hand resting on the bump during a quiet, active spell may catch one. Many partners also find that attending a scan or appointment makes the baby feel real. Hearing the heartbeat, or seeing a hand or a profile on the screen, gives the baby a shape in your mind.
Some partners feel left out of a process that is happening in someone else's body. Others feel pressure to be calm and practical while quietly worrying. Talking about this openly, without judgment, helps both of you. There is no right way to feel at this stage.
For your partner: Tonight, sit together for ten minutes with your hand on the bump, and ask what the baby's busiest times of day seem to be.
Day 147 · 20 weeks 6 days
Water takes the weight off
As your bump grows, some forms of movement that felt easy a few months ago may start to feel heavy on your joints. Water can help. In a pool, your body is supported, the pressure on your back and pelvis drops, and you can move freely without overheating.
Swimming lengths, walking or jogging in the shallow end, and aquafit classes designed for pregnancy are all good options. The water's gentle pressure can also ease swelling in your legs for a while afterward. Breaststroke kicks can strain a sore pelvis, so if you feel pain at the front of your pelvis, switch to a front crawl kick or use a float.
A few precautions apply. Choose a pool that feels comfortably warm, not hot, and skip hot tubs and saunas, which can raise your body temperature too far. Take care on wet floors and steps, as your balance is shifting. Drink water before and after, since you still sweat in the pool.
If you are new to exercise, start with 10 to 15 minutes and build slowly. Stop and rest if you feel dizzy, short of breath or have any pain. Try this: Look up the times for a pregnancy aquafit class or a quiet lane swim near you, and put one session in your calendar this week.