The triple screen is offered to all women near the end of their first trimester or beginning of the second. This tests the mother's blood to look at the levels AFP, hCG and Estriol looking for indications of abnormalities in the baby. For this screening they prick your finger and take blood to be sent off for the screening. It usually takes around a week to process. This is only a screening and gives no diagnosis. If levels of any of the 3 substances comes back abnormal they may run further testing, however getting "false positives" is very common on this screen. To read more in depth on this screening check out this page.
The benefits of this type of screening is knowing if there is a problem early on that needs to be treated immediately after birth or possibly before birth in extreme cases. This is a screen that you can typically opt out of without any problem. I have not had this done, personally, so do not have any personal experience with it.
Along with this triple screen they will also do an early ultrasound to look at the neck folds of the baby, looking for indication of Downs Syndrome. They may also do an early ultrasound to check for dates, particularly if you have an irregular period or are very unsure of conception. Again you can usually opt out of this if you choose to. I had an early ultrasound with 4 of my pregnancies for dating purposes. This pregnancy is the first time I have not had one, and my pregnancy has been much like the others.
Do you have any experience with these? Would you recommend them?