For the past two months now I have missed my period. I'm 27 yrs old and already have two children and having a third would be great, but after 4 negative pregnancy tests I don't know what's going on!
Please can you give me any insight as to what is going on. I am not on the pill or used any type of contraceptive for 12 months now, although I did have a misscarriage in July 2006.

Are you taking your HPTs first thing in the morning? This is important is it is when the concentration of hCG is at its highest.

Also, it might be wise for you to visit your doctor for a blood test to rule out pregnancy and find out exactly what is going on.

What is your age? This is important also.

This is only a small possibility but you could ask at your doctor's. Ask about PCOS it's unlikely if you've conceived children without a problem before but if you have had any kind of slight weight gain it could have brought it on, pcos is policystic ovarian syndrome and is very common, it doesn't always have any symptoms, the symptoms are missed periods, possibly more facial or body hair than usual, gain weight quite easily, sometimes acne.. . there are lots of symptoms actually but you could ask your doctor about it just to see if it could be that causing it, don't take my word for it though because there is only a small chance this could be the problem and I only suggested it because I have PCOS myself and hardly have any symptoms at all, it isn't really a problem and you don't have to go on medication or anything they usually advise you to lose a couple of pounds and it will make a big difference but it took my doctor a very long time to even suggest it could be this so this could be a possible reason, you could research on the internet things that cause missed periods so that you can run a few by your doctor :) Obvioudly I also agree with J_9s answer :)