If you mean aerial drones, some number more than 670,000 UAVs have been registered by the FAA. It has been estimated that something like 1 million will be flying by the New Year 2018. I guess that some 50 industries use drones with something like 30,000+ women and men learning to be commercial, etc pilots.
Amenorrhea is the medical term for the absence of menstruation. âSecondaryâ refers to menstruation that has occurred at least once but has stopped, typically for six months or longer. This is different from primary amenorrhea, a condition in which a woman does not have her first period by the age of 16.
More information about causes of Amenorrhea: 1  Medications, drugs, or substances causing Amenorrhea (12 listings) 2  Underlying causes of Amenorrhea. 3  Amenorrhea as a complication caused by other conditions.  Amenorrhea as a 1  symptom. Medical news summaries relating to Causes of Amenorrhea. 1  Pregnancy. 2  Breast feeding. 3  Exercise - might lead to skipping a period.  Stress - can cause menstrual 1  irregularity. Illness - can cause menstrual irregularity.  more causes...Â».