Pregnancy sickness is often one of the first signs that you are pregnant. Although the exact cause is not known, it's thought the corpus luteum (which will later form the placenta and which produces female sex hormones, oestrogen and progesterone) may contribute.
The sickness tends to end at around 10 weeks when the corpus luteum stops working and the placenta takes over. Eat little and often and nibble on a biscuit before getting up in the morning. Avoid spicy or fatty foods and anything else such as cigarette smoke that might send you rushing off to the bathroom.
You may feel 'premenstrual' thanks to the hormone progesterone, which causes water retention. The same hormone also affects your breasts, making them tender and swollen and making your nipples tingle, especially in cold weather.
You'll also start to notice that glands called 'Montgomery's follicles' become more apparent on the areola (the dark, raised area) around your nipple. Don't cut down on drinking water and go to the loo as often as you feel necessary. Holding back can lead to a urine infection.
Pregnancy hormones mean your blood pressure lowers, causing you to feel faint. Get up slowly after sitting or lying down and try not to stand for too long a period. If you feel faint, sit or lie down with your head lower than your heart.
Taking folic acid?
If you've been trying for a baby and think you may be pregnant, you should already be taking folic acid. If you haven't yet started, go and buy some now! Folic acid helps to prevent neural tube defects such as spina bifida in babies. You won't be getting enough folic acid from your diet, so take a daily supplement, available from chemists or health food shops.
Now really is the time to give up smoking. Every time you take a puff you are adversely affecting your baby. Not only does research shows smoking can cause lower birth weight, but that lower weight can affect your baby in later life. And don't think that a smaller baby means an easier birth, it doesn't! Need help in kicking the habit? Talk to your GP or call QuitLine on 131 848.
Your embryo is only 1cm long at this stage.
Your baby is rapidly growing and changing day by day and these first few weeks are crucial to the embryo's healthy development.
What's developing this week?
The foundations of your embryo's vital organs are now in place so that the heart, liver, kidneys, lungs, thyroid and pancreas can all develop and grow. The eyelids have grown and fused together to protect your baby's eyes and will remain closed for some weeks.
First sight of your baby
Even though the embryo is only 1cm long at this stage, it is possible to detect it with a transvaginal ultrasound scan if there seems to be some doubt about whether you're pregnant or have had a miscarriage in the past.