Week 4

How big is your baby?

By 4 weeks your newly formed embryo is well on his way to becoming a recognisable baby. Although, at the moment, he is too small to be seen. Think poppy seed and that’s the size.

How big is your baby?

By 4 weeks your newly formed embryo is well on his way to becoming a recognisable baby. Although, at the moment, he is too small to be seen. Think poppy seed and that’s the size.

Changes in your body this week

Your body is fast becoming an incubator for your baby. In the very early stages of pregnancy, nourishment for the embryo comes from its yolk sac. It will take around another six weeks for the placenta to be fully formed as its cells are growing deeply into the uterine wall which means that they can establish the rich blood supply so critical for the pregnancy. All the nutrients for your baby are passed through it and the placenta will nurture your tiny embryo right up until the birth.

How your baby is developing

By week 4 your embryo is snug inside the amniotic sac, surrounded by fluid. He is growing incredibly rapidly as the cells divide into several critical parts of the body.

There are three main layers of development:

  • The mesoderm (middle cells) turn into blood vessels, heart, bones and muscles
  • The endoderm (inner cells) becomes the digestive system, including stomach, bladder, intestines and lungs
  • The ectoderm (outer cells) will develop into the nervous system and the brain, plus they add some finishing touches to your baby, such as his nails and the enamel that covers his teeth.

How your baby is developing

By week 4 your embryo is snug inside the amniotic sac, surrounded by fluid. He is growing incredibly rapidly as the cells divide into several critical parts of the body.

There are three main layers of development:

  • The mesoderm (middle cells) turn into blood vessels, heart, bones and muscles
  • The endoderm (inner cells) becomes the digestive system, including stomach, bladder, intestines and lungs
  • The ectoderm (outer cells) will develop into the nervous system and the brain, plus they add some finishing touches to your baby, such as his nails and the enamel that covers his teeth.

Health concerns

The best thing that you can be doing at this stage of pregnancy is to concentrate on eating a healthy, varied diet with plenty of fruit and vegetables and staying hydrated. Giving yourself all of the proper nutrition means that your baby will also receive it, via the placenta.

Harvey J. Kliman, MD, PHD, from Yale University says that a healthy placenta is the “single, most important factor in producing a healthy baby”. He suggests that the main problem which can adversely affect healthy placental development is the risk of intrauterine bacterial infections (UTIs), so if you feel worried that you have a urinary tract infection or you are at risk of getting one during your pregnancy, speak to your GP or midwife as soon as possible.

Are there any symptoms you should be looking out for?

Sadly, some early pregnancies end in miscarriage. If you have a positive pregnancy test very early on (on or around the day of your missed period) but later begin to bleed, this could be what’s called a ‘chemical pregnancy’. This is where conception has taken place but the embryo fails to implant successfully, or doesn’t progress past the blastocyst stage.

If you believe you may be pregnant and you experience bleeding and/or painful cramps, then you should always seek medical advice from a healthcare professional. This is especially important if you have severe pain just on one side, or you are passing large amounts of fresh, red blood and/or big clots. Sometimes these symptoms will be nothing serious, but it’s always worth getting checked out.

Safety first

If you are unsure of any pain, bleeding or other symptoms then you should always get checked over by your midwife or GP. There are some symptoms which occur during pregnancy which can be a sign of more serious problems and it’s vital to act quickly to protect your health and that of your baby.

While it’s generally safe to continue physical jobs during early stage pregnancy, – anything involving long periods of standing, heavy lifting etc – if your job involves contact with toxic chemicals or harmful substances however, you should talk to your GP and maybe your employer about being reassigned to a different role or substituting harmful substances for safer ones.

Important issues this week

Step away from the pregnancy tests! Many women at this stage take multiple tests before they actually believe that they’re pregnant, but this isn’t necessary. Repeat testing doesn’t give you any more security in your pregnancy and it can be very expensive. The only way that you will know for certain that you’re carrying a viable pregnancy is time. It’s frustrating, but you’re better off trying to relax and chill out rather than stressing about the baby.

Generally, a positive result from an over-the-counter test will be reliable – however, negative tests are less conclusive, so if you still feel pregnant, but your test gave a negative result, wait a week and then perform the test again.

Keeping fit, staying healthy

If you already have a regular exercise pattern then you can carry on with that, although it might need some moderation. If you haven’t been exercising regularly prior to pregnancy, then it’s best to consult your doctor or midwife before you start. Staying active and fit throughout your pregnancy will help your body adjust to the greater demands on it and also prepare you well for labour.

Exercise tips for pregnancy include not over-straining just one part of your body, don’t become too breathless (you should be able to hold a conversation easily) and perhaps think about pregnancy-friendly exercise such as swimming or antenatal yoga. If you can’t face sessions in the gym (we’ve all been there) then a walk in the fresh air is a perfectly acceptable alternative.

Looking forward; planning ahead

Within the next four weeks you’re likely to have your first appointment with your midwife, known as your ‘booking-in’ appointment. During this initial meeting, you’ll be asked extensive medical questions about both yourself and your partner, primarily to find out if there are any underlying conditions which can make pregnancy more risky.

If you have any pre-existing health concerns then it would be wise to prepare to answer questions on this. Things to mention would be any type of physical illness or injury, any mental health issues such as bipolar affective disorder, depression and anxiety and also more difficult topics such as drug or alcohol problems. Your midwife will not judge you and she always be able to point you in the right direction to access any help or support you might need.

Important – If you or your child are unwell you should seek medical advice from a professional – contact your GP or visit an A&E department in an emergency. While My BabyManual strives to provide dependable and trusted information on pregnancy and childcare 24/7 via our website pages, we cannot provide individual answers to specific healthcare questions.
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