Your pregnancy at 4 weeks
Even though you may be 4 weeks pregnant your pregnancy test could still return a negative result. The hGC or pregnancy hormone in your urine might still not be of sufficient quantity for a simple over-the-counter test to pick it up. It is advisable to wait with another test. hGc levels almost double every 48 hours and peak around 6 or 7 weeks which is the best time to do another test. If you can't wait or have experienced complication with previous pregnancies such as ectopic pregnancy or miscarriage you should make an appointment to see your doctor who can do a blood based pregnancy test.
Blood pregnancy tests are usually carried out in surgery with at least 2 samples of blood being taken over a 48 hour period.
What's happening with mum
In a word - hormones.
At around this time progesterone levels will also increase in your body. This hormone stimulates the growth of breast tissue, helps keep the lining of the uterus thick and healthy to support the fertilized egg as well as relaxing the uterine muscle to allow it to expand and accomodate the fast growing embryo. However, it also relaxes other muscles and can cause familiar pregnancy symptoms such as heartburn, indigestion and constipation.
Estrogen is one of the key hormones, helping plump up your breasts, increasing blood flow to mucus membranes and giving you a healthy, growing uterus. Increased estrogen levels do have their drawbacks however and you may start to notice your skin becoming blotchy, have more headaches or what seems like the symptoms of an allergic reaction such as sniffles, sneezing or a blocked nose.
What's happening with baby
This might not look like much but there is already a lot happening with your baby. Still only a little ball of cells (blastocyte) she is nestling herself into your uterine wall. Over the next few weeks the cells will continue to multiply with half eventually becoming baby and the other half forming the all important placenta which will not only filter harmful substances from the blood before they get to your baby but will also provide vital nutrients and carry away waste products to be deposited in your urine.
It is all about taking care of yourself. A healthy you will go a long way to a healthy baby. It is advisable to avoid smoking and alcohol now that you are pregnant and to eat regular, healthy meals. Regular check-ups with your doctor, midwife, care provider is also advisable as they can monitor your progress, advise and supply any dietary supplements or vitamins and just be a general support and sounding board for any questions or concerns you may have.