Pregnancy calendar

The 1st trimester: Week 4

You think you may be pregnant? If you're very sensitive, you may notice feelings of fatigue, queasiness, bloating, and breast tenderness, and maybe even changes in your skin. You are able to tell approximately a week after conception that you are pregnant by taking a sensitive pregnancy test at your GP or clinic. A home pregnancy test may give a false negative at this stage however.

Your baby

How your baby is growing

Congratulations, you may have just found out you're pregnant! At this stage, your baby is a tiny speck, with something of a tail, like a tadpole.

The embryo consists of three different layers of cells with the outer layer forming what will eventually become your baby's brain, backbone, skin, ears and eyes. The middle layer will turn into bones, muscles, sex organs and heart, while the inner-most layer will develop into your baby's lungs, liver and digestive systems.

This is a time for vigilance, as in many respects the first four weeks of life are amongst your baby's most hazardous. If you experience cramping, spotting or bleeding, lower abdominal pain or continual vomiting contact your doctor immediately. If you have had a previous miscarriage it is particularly important you see your doctor early as there may be hormone levels to be checked.

Your body

How you may be feeling:

This may be the week that you receive the age-old sign: most women say that they suspected they were pregnant because of a missed period (others cite nausea, fatigue and intuition). Also, even though it's early days, some women notice altered taste preferences during this time, including food cravings or aversions or an increase or decrease in appetite. Don't despair should you feel ill - nausea is caused by high hormone levels and research shows that even this unpleasant stage could have benefits later in life. Severe morning sickness has shown to decrease your odds of getting breast cancer by 30%.

Tip of the week

At this stage, you might like to know about (and be slightly concerned by) the plethora of tests to expect during the course of your pregnancy.

Ask your doctor for full details on your first visit, but here's a preview:

General tests:

• Haemoglobin (for anaemia)
• Blood group and blood group antibodies
• Blood infections, particularly HIV and hepatitis B
• Immunity to German measles
• Glucose tolerance (to exclude gestational diabetes)
• Vaginal infection (through a lower vagina swab)
• Your baby's growth and wellbeing (through repeated ultrasound scans)

At 11-14 weeks:

• Depending on whether you fall in to a high-risk category, you may want to assess the possibility of your baby having Down's Syndrome. A detailed ultrasound scan will measure the baby's nuchal (neck) fold and blood tests will be used to calculate your risk.

At 16 weeks:

• Blood test to screen for spina bifida

At 22-23 weeks:

• Detailed foetal scan to check for foetal abnormalities that might require special attention during delivery.