This is probably the most baffling question that I get asked on a regular basis. Most people want to know months not weeks. I usually just say what my due date is because that is fairly constant.
So... here's the deal. According to my Japanese Doctor, I'm 29 weeks pregnant today. This is based on a measurement taken early in pregnancy and the size of the fetus at that time. I think this is fairly accurate. If I go off of last period which is what most of the pregnancy calculators do, I'm 30 weeks tomorrow. The baby is fully baked at 37 weeks and my due date is at 40 weeks which is May 25th or 19th depending on which number you go with. I'm telling people May 25th.
If you want to know in months where I'm at, this is where it gets crazy. Lets stick with the 29 week scenario for simplicity. According to the Japanese system, I'm at 8 months and 1 week. According to the "What to expect when you are expecting" book I'm at 7 months and a week. However, if I just look at a calendar and count months, I have one more week in month 6. So... how many months pregnant am I?