Why have i missed 2 periods?

I always had negative pregnancy tests in early pregnancy, and it was a sign that the pregnancies weren't very secure, so I had a few miscarriages. However, the good news is that even the pregnancies that resulted in babies started with negative pregnancy tests. So it could be a sign that in early pregnancy your body isn't making enough of the pregnancy hormones and you are at higher risk of miscarriage, but this doesn't automatically mean you will miscarry. On the other hand, there might be some other explanation - get a doctor's appointment to get it checked out. However, I did once hear a doctor say that when a woman presents with missed periods there are 3 explanations you should consider before you start looking at other possibilities: 1. She's pregnant. 2 She's pregnant. 3. She's pregnant!