First Trimester

Congratulations your pregnant

This guide presents a summary of each week both for you as well as for what's happening with the little one inside. So click on the week that relates to you and you can quickly see what may be relevant to you. We have tailored a summary as well as more detail information for those that want a little more detail. Wherever you see italics and or click thru you will be taken to a page with more information. At SRC we are helping women have happier and healthier pregnancies as well as helping them speed up their recovery, so they can do what matters most - is nurturing their newborn children.

  • Week 6

    Your Baby

    • Embryo 5-6mm length
    • Heartbeat about 80-100 bpm
    • Spine developed
    • Brain developing

    Focus on you

    • Hormonal changes
    • oestrogen & progesterone
    • Possible nausea and Vomiting


    Congratulations, you are 6 weeks pregnant!

    Your baby is known as an embryo for the first 7 weeks. It is then referred to as a foetus from the eighth week of conception. The embryo refers to the first stage of development of a baby from the moment of fertilization.

    Your baby’s length crown to rump is approximately 5mm. Crown to rump measurements are used because baby’s tiny legs are not yet formed properly. The spine has finished developing and the brain is beginning to develop. The various regions and chambers of the brain continue to grow and further define. Little depressions on both sides of its head will form the ears. Bulging black dots on the front/side will form the eyes and a small bump on the front of the head will form the nose. Heartbeat is getting faster day by day and is around 80-100 bpm.

    The embryo develops 2 cavities, the amniotic sac and the yolk sac. The amniotic sac continues to expand and progressively envelops the embryo and body stalk. The yolk sac never reaches a large size and dissolves as soon as the foetus begins to obtain nourishment from the placenta. The body stalk that connects the embryo to the developing placenta gradually becomes elongated and develops into the umbilical cord, containing 2 arteries and a one vein which provide nutrition.


    This week you may start to develop other signs of pregnancy, such as nausea possibly accompanied by vomiting, breast tenderness and an increase in breast size. Increased frequency of urination, fatigue, and constipation are all common symptoms now.

  • Week 7

    Your Baby

    • Embryo now 10-11mm long
    • Heartbeat 140 bpm
    • Umbilical cord now developed

    Focus on you

    • Breasts larger and tender
    • Increased size of veins in breast area Constipation
    • Tired most of the time


    By the end of the week, the crown to rump measurement has increased to about 10-11mm. The embryo’s heart beat is now about 140bpm.  Growth during week 7 is linked to the constant development of your embryo’s internal organs and body.  

    Following further brain development during week 6 your baby’s head is pushed forward and becomes rounder. The eyes and ears look like little depressions on the side of the head, and the nasal cavities and mouth are being developed. Brain cells are being developed at a rate of 100 cells per minute.

    Your embryo is now 10,000 times bigger than at conception!

    Limbs are noticeable, and development of arms and legs advances to where hands, arms and shoulders start to form. The umbilical cord is also developed and has been closed off within the wall of the amniotic sac that surrounds your baby.


     No noticeable external signs of pregnancy are obvious as yet but your body is going through enormous changes, your progesterone and oestrogen hormones levels have significantly increased. As a result there are other noticeable effects.  Breasts become enlarged and tender due to hormonal effects and the increase in blood supply. Milk glands grow in preparation for the production of milk and breastfeeding. Veins on your breasts are more visible. Your nipples will protrude more and the areolas surrounding them will darken as your pregnancy progresses.

    can occur early in pregnancy and may last until after the baby is born. It is caused by the hormone progesterone which slows down bowel movements.

    Tiredness is very common, especially in the early stages of pregnancy.

    You may find you are particularly sensitive to the heat and there is a slight increase in body temperature. This is as a result of the extra circulating blood volume in your body and the hormonal changes in the early weeks.

    Nausea and vomiting can occur at any time of the day and may be problematic for some women. For most women, morning sickness eases around Week 12 but in some cases it can continue to Week 16. Human chorionic gonadotrophin (HCG) is said to be responsible for this.

    Fainting and headaches are also common and related to progesterone which dilates blood vessels (vasodilatation). This changes as the pregnancy advances because blood volume increases to fill the larger vessels.

  • Week 8

    Your Baby

    • Foetus now 14–20mm long
    • Heartbeat 160 bpm
    • Limbs starting to form
    • Valves of baby’s heart are developed
    • Bones are starting to develop but are soft

    Focus on you

    • Uterus changing shape
    • Slight increase in body temperature
    • Possible back pain


    This week your baby can officially be called a foetus.  Your baby’s heart has begun to develop and is now forming valves. Circulation has started to form and nerves also begin to grow. Your baby’s heart beats at around 160 bpm. The two buds that will become the lungs are growing. The intestines and digestive system start to form. They divide to create the oesophagus, stomach and small intestine. Other glands and organs are also developing and the first parts of the reproductive system are present.

    Your baby is approximately 14-20mm in length and is rapidly growing.

    Your baby's face is beginning to take shape. Eye muscles and eyelids have emerged, and by the end of the week the nasal passages will have formed and the nose tip will be visible. Its eyes look to be located very far apart and more to the side of their face than where they will eventually be. Baby’s fingers, toes and lips and legs are becoming more clearly defined.

    The valves in the heart that started forming last week can now be seen as the aortic and pulmonary valves. Lungs are developing and the bronchi are forming. The skeleton has also started to grow.

    The internal and external parts of the ear are also forming. Ear openings are present, and the middle ear (responsible for hearing and balance) is there, but it is not possible for your baby to hear as yet.


    Your uterus is increasing in size, and while you may not show you may notice your clothes getting a little tighter.

    You may become conscious of some lower back pain from week 8 onwards. This may be something you’ve never experienced before your pregnancy. Back pain along with pelvic girdle pain can come and go throughout pregnancy and is influenced by the elevated levels of the hormone Relaxin. If the pain is more than minor discomfort you may find pain relief with SRC Pregnancy Shorts/Leggings.

  • Week 9

    Your Baby

    • Foetus now 20-30mm long
    • Fingers and toes developing
    • Heartbeat 180 bpm
    • Eyes bigger with some pigment
    • Ears forming inside and out
    • Tooth buds forming

    Focus on you

    • Some fluid retention possible
    • Possible morning sickness increased
    • Vaginal discharge


    Your baby is approximately 20-30mm in length.

    Your baby's neck area is becoming more distinct and their head is more rounded. The eyes are still developing, and now the eyelids are present. The eyes will then stay closed for a great part of your pregnancy. External ears are still developing both inside and out. The nasal passages are opened this week. Your baby's organs are also forming. Inside their mouth is the tiniest of tongues and even their tooth buds are forming in their jaw.

    Fingers and toes are starting to form and develop at quite a fast rate. Your baby's heart rate is approximately 180 beats per minute.


    Due mainly to fluid retention, your face will look fuller and your skin may be looking very healthy. You may also find that your gums bleed easily (gingivitis) when brushing your teeth.

    Morning sickness and severe tiredness may still be an issue.

    You will possibly find your vaginal discharge has increased by now. This is normal throughout pregnancy.

    As your uterus gets bigger you will probably find that your waist line is beginning to increase. Before pregnancy your uterus is about the size of your fist.  After six weeks it will grow to about the size of a large orange.

    As the uterus enlarges you may feel a cramping sensation or pain in the lower abdomen or on your sides. This is common. Later in pregnancy these sensations are called "braxton hicks" contractions.

    During pregnancy your blood volume increases by about 40-50% to service the needs of your expanding uterus. The largest increase is during the second trimester.

  • Week 10

    Your Baby

    • Foetus 30-40mm long
    • Kidneys producing urine
    • Boys are producing testosterone
    • Mouth opens and shuts
    • Eyes fully formed but remain shut

    Focus on you

    • Food cravings
    • Pants may be getting tight around the waist.
    • Increased flatulence


    This week your baby is between 30 and 40mm in length and weighs approximately 5 grams. The placenta weighs approximately 20g.

    All organs are now present and as your baby becomes fully formed, it will increase in size and weight more rapidly. The head is still large in comparison to the rest of the body, but the body begins to grow and uncurl.

    Your baby’s fingers and toes are clearly formed by week 10 and they are developing finger and toe nails. Your baby can bend its limbs this week, at its elbows and is able to flex its wrists.

    Your baby’s kidneys are filtering their blood and producing urine this week. They are also secreting digestive juices in their stomach, getting ready for dealing with the amniotic fluid they’ll be swallowing soon.

    If your baby is a boy, his testicles are already producing testosterone.

    Your baby’s head is still large in proportion to the rest of its body, by week 10 your baby has a neck and all of the bones in its face are formed.

    A layer of fine hair known as lanugo is now covering your baby’s body.

    The eyelids have finished forming, but these won't open until much later in the pregnancy.


    Week 10 You

    You have probably also been experiencing certain food cravings. This perhaps is your body’s way of letting you know what it requires.

    Your pants may now start be getting tight round the waist as your uterus grows.

    Increased flatus, wind or gas is really common during this time and may sneak up on you at the least convenient time.

  • Week 11

    Your Baby

    • Foetus 42-60mm long
    • Baby has sleep and awake time
    • Swallowing amniotic fluid and urinating
    • Girls ovaries start to develop

    Focus on you

    • Uterus growing and outside the pubic bone Breasts may be less tender
    • Nausea may be improving
    • Nails and hair grow more quickly
    • Weight gain


    Your baby is approximately 42-60mm long and weighs about 8 grams.

    The baby is very active and moves its arms and legs.  It also has little sleeps. Your baby can now also suck and swallow. Your baby drinks the amniotic fluid surrounding itself and then excretes it via the kidneys. The amniotic fluid is constantly being replaced.

    Along with the baby, the placenta is growing to meet your baby's growth and nourishment demands.

    If your baby is a girl her ovaries are starting to develop.


    Your uterus may be palpable above your pubic bone.

    Due to hormone changes in pregnancy, a woman's gums tend to be softer, which can lead to bleeding gums.

    You may also notice differences in your fingernails and hair (more fragile) because they are growing at a different rate to what they usually do. These changes are because of the effects of pregnancy hormones.

    Your weight may start creeping up slowly from now on.

    Your breasts may not be as tender as they were.  Montgomery's tubercles or little bumps start to form on the areolas and secrete oil to keep the area soft and supple. 

  • Week 12

    Your Baby

    • Baby 60mm long
    • Bone marrow producing blood cell
    • Baby moving a lot now
    • From now pituitary gland starts to work
    • Baby can suck its thumb

    Focus on you

    • Ultrasound, nuchal translucency, to check for Down’s syndrome
    • Skin around nipples getting darker
    • Nausea may start to be less now
    • Risk of miscarriage has significantly reduced


    You may begin to notice that morning sickness is improving and you will begin to feel much better.

    As your uterus gets larger it will move outside your pelvis which will create further thickening of your waist line. This also takes pressure off your bladder and you will not need to visit the bathroom so often!

    The skin around your nipples may be getting darker and you also may notice darker patches of butterfly-shaped pigmentation on your face. This is known as chloasma. Some women may also develop a linea nigra, which is a darkly pigmented line that runs from the umbilicus to the pubic area. These are both due to hormone changes and fade soon after birth.

    Nuchal translucency/ screening nuchal fold - this is an ultrasound assessment to identify a specific abnormality of the foetus that can be linked to Down's syndrome. The assessment is generally performed between 11 and 13 weeks. It is a non-invasive way of measuring the risk of having a baby with Down's syndrome, and has no risk of miscarriage. The ultrasound measures the appearance and amount of fluid that normally gathers under the skin at the back of your baby's neck. When the foetus has a chromosomal disorder the fluid tends to be at an increased level. The pick-up rate is thought to be 75-80% depending on age of the mother. Should this test indicate an increased level of fluid you doctor may recommend further testing e.g. Chorionic Villus Sampling (CVS).

    CVS is a test in which a small sample of the chorionic villus or chorion, (the material lining the uterus that will develop into the placenta), is sampled and tested. This is done to test for genetic / chromosomal abnormalities such as Down's syndrome, sickle-cell anaemia, thalassaemia, cystic fibrosis, Huntington's chorea, muscular dystrophy and haemophilia. CVS is done under ultrasound guidance; the sample is taken either through the abdomen or, less commonly, the vagina depending on the way the baby is lying and the preference of the doctor doing the test. There is a very small chance that the result may be difficult to interpret and the test may need to be repeated. CVS is usually done between the 11th and 13th weeks of pregnancy and should not be done before the 10th week. When CVS testing is performed by an experienced doctor, the risk of miscarriage in one in 50.