Posted by 
Female infertility is inability to contribute to conception or unable to carry a pregnancy to full time.
Researchers at the University of Montreal Hospital Research Center have new explanation for female infertility.
They discovered that microtubules that coordinate chromosome segregation during cell division behave abnormally in older eggs.
Women are born with a fixed number of eggs, which remain inactive in the ovaries, one egg is released every month during menstruation.
One of the causes of infertility in female is defect in egg that causes abnormal number of chromosomes, the egg can cause miscarriage and down syndromes, fertility decline start at 35 years.