no 'safe' time to avoid pregnancy

No ‘safe’ time to avoid pregnancy:

For 50 years, doctors have believed that about a dozen follicles, or egg sacs, grow at one time during a woman’s menstrual cycle. From this group, only one follicle actually bursts and releases an egg, while the others shrivel and die.

But, in a finding that left even researchers “flabbergasted,” University of Saskatchewan scientists have found this pattern of follicular development actually occurs two to three separate times during a woman’s menstrual cycle. What’s more, 40 per cent of women have the biological potential to ovulate more than once during a cycle.