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Pregnancy: 40 Great Weeks!

Your at-a-glance guide to what's happening to you and your baby

Posted: 6 August 2009
by ThinkBaby

Your pregnancy is one of the most exciting things that’ll happen to you, but it can also be bewildering and a bit scary – just what is happening to your body? In the ThinkBaby Pregnancy pages you'll find detailed features and advice (with links to supportive forum chats) about all of the health and well-being issues you might need to know about. But here we give you a quick tour of your 40 weeks… and don't forget you can sign up to our weekly fetal development emails!

Just pregnant?
You probably won’t even know it yet, but your baby is growing already. Your womb is around the size of a plum, and the embryo is only 0.2mm long!

Weeks 5-7
You may know you’re pregnant by now. Your baby is developing eyes and a brain, and though the birth may seem ages away, your body is already gearing up for it and you might be noticing some changes. Blame it on those pesky hormones that’ll be with you for the next few months. The increased levels of progesterone and oestrogen will be getting to work around now, making your breasts bigger (and possibly more sensitive – but just focus on the impressive cleavage!).
Progesterone will also be wreaking havoc with your tummy. If you can’t zip up your skinny jeans, it’s not the fault of your baby, who’s only around 1cm long, or your womb, which has expanded only slightly, from the size of a plum at conception to the size of an apple in week six. Rather, your bowels are more sluggish than normal in these first few weeks, so make sure you eat lots of high-fibre foods and drink plenty of water to keep everything moving.
It’s possible that you won’t really fancy eating anything if you’re suffering from nausea, which can strike at any time of the day, not just in the morning – again it’s a side effect of the progesterone. If you can stomach it, graze little and often – sometimes ginger biscuits can quell the sickness.
One more thing to look out for is dizzy spells. Don’t worry, this is perfectly normal, and yes, you guessed it, it’s down to the progesterone. It makes your veins expand, which lowers your blood pressure and brings on that feeling of faintness – so put your feet up.

Weeks 8-10
Thought you’d seen the back of mood swings once the PMS stopped? Perhaps not. Advise your partner to keep out of the way, keep the house clean and keep bringing you cups of tea. You might also have cravings for strange foods – even ones you didn’t like before – so if he wants extra Brownie points, he can keep you topped up with bowls of gherkin-garnished ice cream.
It’s not just progesterone racing round your body now. You may notice that your thyroid gland is taking pride of place in your neck, because the pregnancy hormone human placental lactogen is stimulating it to produce extra thyroxine, which can also affect your metabolism. Oestrogen is bulking out the muscle fibres in your ever-expanding womb, too, preparing it for contractions and labour.
You’ve probably made your peace with your bigger breasts by now – just in time for your nipples to start changing. The skin around your nipples (the areola) may become larger and darker. The little bumps around your nipples (called Montgomery’s tubercles) also get bigger, ready to secrete a fluid to lubricate your nipples while you breastfeed.

Weeks 11-12
Are you looking in the mirror and thinking you look five years younger? It’s a benefit of those hormones – nature’s very own airbrush, decreasing fine lines and wrinkles.
You probably don’t feel like going to the gym (in fact, cutting out the high-impact exercise is a good idea, although that’s no reason not try swimming or brisk walking), but your heart is getting a good workout anyway, as its rate has to increase to pump the blood to support you and your baby. By the end of your first trimester it will be producing 40 per cent more blood than normal! Your breathing rate increases too, so that you get enough oxygen to the baby, and because your thyroid gland is still working overtime your metabolic rate increases by 10-25 per cent. Don’t take that as an excuse to eat for two, though – continue to eat a healthy balanced diet.
There’s got to be a downside, right? Well, you may be scurrying off to the loo every 10 minutes. This is because your womb is still well down in your pelvis, and until it moves up and away it may put pressure on your bladder.

Weeks 13-16
Where’s that pregnancy glow you were promised? You may get flashbacks to your schooldays as your skin suddenly develops its own oil slick, or dries out and starts flaking. It’s not forever, though, and should clear up after the birth. Get yourself some shiny new make-up goodies to help you cope.
And where’s your waist gone? No longer do you look vaguely unkempt – that extra poundage is a very visible bump now. It’s an excuse for a shopping spree, and don’t forget to invest in a good maternity bra as well.
Rather unpleasantly, you may find your nose is blocked up and possibly bleeding – it’s the dilated veins again. You may also notice your gums bleeding when you brush your teeth, for the same reason – make sure you tell your dentist that you’re pregnant, and take advantage of your free dental care!

Weeks 17-20
You may find you’re suddenly blessed with the thick glossy locks of a Hollywood goddess. Bonus! It’s because the pregnancy hormones have interrupted your hair’s normal cycle, and this can leave it in a permanent growth stage.
Another plus around now is that as your bump gets bigger and your womb moves up into your abdomen, it takes the pressure off your bladder – no more sprints to the loo! If you’ve not already grabbed the opportunity to buy an entire new wardrobe, now would be a good time. In addition to your bump, it’s likely your bottom will become rather well padded as it stores up fat ready to convert to energy during breastfeeding.
Fancy a beach break? Take it now, before you get too big to travel! The extra oestrogen in your system means you’ll tan more easily, though obviously you’ll still need sun block – and because of all that extra blood pumping round your body, you may find you’re hotter and sweating more. If you’ve got freckles, they may become more prominent as the pigmentation in your skin (melanin) turns darker. You may even develop a ‘mask of pregnancy’ (a darker area around your forehead, nose and chin), but it’s nothing to worry about and will disappear after the birth.

Weeks 21-24
That progesterone’s not finished yet! It may be working to relax the valve at the top of your stomach, meaning you get heartburn. Your doctor or midwife will be able to recommend suitable antacid tablets, while sleeping propped up on pillows may also help. Your breasts are on full alert, ready to feed your baby. The dark blue veins you’re noticing are pumping extra blood to them as milk ducts begin grow.
Your kidneys are working overtime too, processing 25 per cent more blood than usual, and your womb needs five times more blood than usual. Don’t fret if you see a dark line running from your bellybutton down your tummy. This is called a linea nigra – it’s entirely normal and will fade after you have your baby.
With all this going on, it’s the perfect time to pamper yourself. Your nails may be growing faster, or they may be more brittle and break more easily, but either way it’s a good excuse for a manicure and pedicure!

Weeks 25-28
All sorts of stretching is going on: gums swelling, chest expanding, and even your bellybutton popping out as your womb moves up and above it! You may feel a stitch-like pain going down the side of your tummy – this is nothing sinister, simply the uterine muscle stretching.

Weeks 29-32
Ever more expansion! Puffy hands and ankles are the norm due to water retention, so get some rest. Your baby is still growing, too, and may push your lower ribs out to get more room. It’s no wonder that backache is a common complaint from women at this stage. Make sure the small of your back is well supported when you sit down, and always roll on to your side before pushing yourself up if you are lying down.
Remember those stretchmarks you developed when adolescence kicked in? Something similar is happening now. They’ll fade from red to silvery-white and eventually be more or less unnoticeable after the birth. If you want to hasten their disappearance, start slathering on that moisturiser now!
Another unwanted side-effect may kick in around now, in the form of your breasts leaking colostrum – the watery pre-milk that will feed your baby for her first few days. Don’t worry if this does happen: it’s unlikely to be enough for other people to notice.

Weeks 33-36
You may be horrified as your face swells up! It’s due to changes in the way the fat in your body is distributed, caused by oestrogen and a steroid hormone called cortisol. If you have lots of water retention, your face may also feel a bit bloated. (Mention this to your midwife, as excessive fluid retention can be a sign of a rare but potentially dangerous condition called pre-eclampsia.)
If you think you’re going into labour early, it’s a possibility, but it’s more likely to be Braxton Hicks contractions – ‘rehearsals’ showing that your body is limbering up for labour. The ligaments in your pelvis will also be stretching, ready to push your baby out. Your baby is getting bigger and bigger (weighing around 2.5kg now), and will be pushing on your diaphragm and lungs. Good news for you because your baby is fit and healthy, but not so nice as you find yourself struggling for breath if you exert yourself. Slow down and take a break!

Weeks 37-40
Those frequent toilet trips are back with a vengeance as your baby pushes down into your pelvis, and as she prepares to be born her head prods at your pelvic floor muscles. The advantage is that it’ll be easier to breathe again as she moves down through your abdomen!
Your cervix is now ripening for labour: it’s getting softer and thinner to make your contractions more effective. You’re all ready to go – it won’t be long before you meet your baby!

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