a single complete execution of a periodically repeated phenomenon

the time in the menstrual cycle when fertilization is most likely to be possible (7 days before to 7 days after ovulation)

the phase of the menstrual cycle during which the lining of the uterus is shed (the first day of menstrual flow is considered day 1 of the menstrual cycle)

the second half of the menstrual cycle after ovulation; the corpus luteum secretes progesterone which prepares the endometrium for the implantation of an embryo; if fertilization does not occur then menstrual flow begins

that time during a woman's menstrual cycle during which conception is least likely to occur (usually immediately before of after menstruation)

the time in the menstrual cycle when fertilization is most likely to be possible (7 days before to 7 days after ovulation)

the phase of the menstrual cycle during which the lining of the uterus is shed (the first day of menstrual flow is considered day 1 of the menstrual cycle)

the second half of the menstrual cycle after ovulation; the corpus luteum secretes progesterone which prepares the endometrium for the implantation of an embryo; if fertilization does not occur then menstrual flow begins

that time during a woman's menstrual cycle during which conception is least likely to occur (usually immediately before of after menstruation)