Week 6 of Pregnancy | How Big is Your Baby at 6 Weeks?

Pregnancy is a time of huge change for you, your body and your life. Our guide will help you through this amazing time, letting you know what to expect at each stage and, most excitingly, what your baby is up to each week.

At six weeks, your baby is the size of a grain of rice!

At six weeks of pregnancy, your baby is around 5mm (0.25in) in length, which is around the same as a grain of rice. They also weigh around 1.1g (0.04oz) and don’t look much like a human being just yet (1).

Your baby’s heart starts to beat this week!

Although they may be the size of a rice grain, there’s a lot going on in that tiny little body.

Your baby’s heart is still developing, but it’s the first organ to start functioning and week six is when the heart starts beating (2), although it’s more of an electrical flutter at this stage.

Other organ systems – digestive, reproductive and urinary – are not too far behind the heart.

The neural tube, which develops into your baby’s brain and spinal cord (3), closes over this week.

The optic ventricles, which form your baby’s eyes (4), develop this week, as well as features such as the nose, jaw and ears. Your baby even has tiny limb buds now.

How you’re feeling at six weeks pregnant

You don’t look pregnant, but you might be starting to feel pregnant around now. Your pregnancy hormones (5) are probably rising to noticeable levels at week six and they often bring nausea and tiredness along with them.

Not all pregnant women feel sick or tired at six weeks of pregnancy, or even later on, so don’t worry if you don’t feel any different or have any pregnancy symptoms. You might have fleeting feelings of nausea or fatigue or they might last for a few days here and there.

Feeling tired in early pregnancy

Fatigue is a normal feature of early pregnancy. Those pregnancy hormones – progesterone in particular – make you feel sleepy (6) and your body is working very hard to grow a placenta. Add in the emotional aspects of finding out you’re pregnant, plus any nausea you might be feeling and it’s no wonder you’re tired!

Nausea and vomiting

Around 80% of pregnant women have some degree of nausea and vomiting of pregnancy (NVP). We call it morning sickness, but many women find it can strike at any time of day and even last all day.

We’re still not sure why NVP happens, but the guilty party is probably the pregnancy hormone human chorionic gonadotropin (hCG) (7), as well as the rising levels of progesterone and oestrogen.

Frequent weeing in early pregnancy

Another symptom of early pregnancy is frequent urination (8). During pregnancy, the volume of blood and fluid in your body rises and as this happens, your kidneys have more work to do and their increased efficiency means increased time in the bathroom for you.

There’s also the pressure of your growing uterus on your bladder, which means you’ll feel the need for a wee more regularly than before.

Staying healthy at six weeks of pregnancy

At six weeks of pregnancy you might not feel much different, but it’s a good time to start eating healthy foods (9), drinking plenty of water and avoiding tobacco and alcohol (10).

If you are feeling tired, then you should get some extra rest. If you’re working during the day or have other responsibilities then try to get to bed an hour earlier.

Avoid caffeine, especially later in the day, as it could prevent you from sleeping when you do manage to go to bed early.

Exercise can also help you to fall asleep faster at night and eating regularly will help to keep your energy levels stable.

Staying hydrated in early pregnancy

If you are making a lot of bathroom trips, you can at least rest assured that you’re well hydrated, which is important for you and your baby.

While weeing lots throughout the day can be annoying, you shouldn’t delay going to the bathroom because you could end up with a urinary tract infection (11). When you do go to the toilet, lean forward slightly to help you to empty your bladder completely.

Dealing with morning (or all-day) sickness

Try to eat small snacks in between meals to keep your blood sugar stable. Eating a large meal in one go can make you sick, so treat your stomach gently.

If you’re particularly sick in the mornings, eat some whole wheat toast before you get out of bed so you bring up your blood sugar before standing up.

If you have severe nausea (12) or you've been struggling to keep food and drink down for 24 hours or more then call your GP as you might need some help. There are safe antiemetic medicines you can take in pregnancy to reduce your NVP so that you can get enough to eat and drink.

Things to think about at six weeks pregnant

You should continue to take your folic acid (13) and any other prenatal supplements your doctor has recommended.

Rest as much as possible and stay well hydrated by aiming to drink at least 1.5 litres of water each day.

Make an appointment to see your GP if you haven’t already so that you can start off your antenatal care. Your first midwife appointment is only a couple of weeks away!

If you’re very tired and/or sick, consider telling one or two close people that you’re pregnant so that they can help and support you until you can “go public’.

Start a pregnancy diary or photojournal to create memories of this special time.