I missed my period for last 2 months took pregnancy test all negative. What else causes 2 missed periods?

Depends. You do not state your age. If it is the beginning of menopause, it is normal. If you are young it is not and it also depends on whether there are other symptoms. See youor doctor.
Many Reasons. This can happen for many reasons including stress, hormonal dysfunction and depending on your age peri menopause or menopause. If you have not resumed your periods please consult with a doctor.

Related Questions

I'm two days late and have a white thick diacharge? I took a home pregnancy test a few days before my missed period but it was negative.

Repeat HPT. Repeat the home pregnancy test or have blood drawn to determine if you are pregnant. The thick white discharge could very well be a yeast infection. Have your doc or a gyn check it out and determine if it needs to be treated. Good Luck.

Spotting since 11jan on & off missed period last month still spotting this period was due 3 days ago took pregnancy test neg my dr said not to worie?

Home pregnancy tests are very accurate. They are the same tests used in a doctors office. They can detect a pregnancy 7-10 days after conception. The best time to take one is when you miss your period.  if you doubt the result you can repeat it in 1-2 days. If you were pregnant the hormone level would rise enough for detection.