pregnancy-week-by-week

3 weeks pregnant

You and your baby's development

What's happening in week 3 of your pregnancy

You are 3 weeks into your pregnancy – here's the science bit!

At a glance

  • Your body will be awash with hormones at this stage
  • You may get some PMS style feelings such as sore boobs and cramps
  • It is good to start thinking about lifestyle changes you may need to make

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Your baby at 3 weeks pregnant

Three weeks into your pregnancy, and you might be wondering just how this little miracle occurred (as in the science bit – we'll assume you know the other part!).

So here goes: the joining of your partner's sperm and your egg at the moment of conception resulted in a ball of cells (or a blastocyst, if you want to get really technical) which is now starting the 6 day journey from the fallopian tube to the uterus where it will attach itself to the lining of your womb – and in nine months’ time, will result in a real live baby in your arms!

Amazingly, although you won’t know for a few months (or until the birth) the sex of your baby has already been determined. The fertilised egg contains 46 chromosomes with 23 from you and 23 from the dad. You as mum will always provide the X chromosome but the dad can provide an X or Y chromosome. XX and you’ll be having a girl, XY and you’ll have a little boy in 9 months’ time!

Read more on early pregnancy:

You at 3 weeks pregnant

Even though your body is awash with hormones, you are probably feeling pretty much the same as usual at the moment – you might even by checking your diary and stocking up on the san pro in the naïve assumption that your period is due any day! Any signs of pregnancy now are likely to be very similar to those you experience just before you come on – perhaps some mild cramping, sore, heavy boobs, and generally PMS type feelings. Amazing to think what is actually going on in there!

What to think about this week

Discovering you are pregnant is obviously a totally joyous occasion – but it is also one that can throw up a few practical issues too! You might need to think about making some big lifestyle changes, such as moving house, changing your car, or even re-thinking your long term career plans.  Babies certainly make a huge financial impact on parents, too, so it is never too early in your pregnancy to start budgeting for all the things you are going to need, from nappies through to travel systems! Have a look at our money and finances pages for lots of helpful advice on family finance.

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At a glance

  • Your body will be awash with hormones at this stage
  • You may get some PMS style feelings such as sore boobs and cramps
  • It is good to start thinking about lifestyle changes you may need to make

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