Physiological period refers to the period of menstruation. Generally, it is not easy to get pregnant in the week before menstruation because most women do not ovulate or the follicles have already been ovulated during this period, so it is not easy to get pregnant, but there is also the possibility of pregnancy.
The normal female menstrual cycle is characterized by the fact that ovulation occurs 14 days before the next menstrual period, and one week before menstruation, the egg has been discharged. Because after the egg is discharged, the best time for conception is within 24h after ovulation, and if it is more than 24h the egg will lose its vitality, so it is not easy to get pregnant a week before menstruation.
In some cases there can be accidental ovulation, or in some cases the egg survives for a long time, so there is also a possibility of pregnancy a week before menstruation.
If a woman wants to determine whether she can get pregnant the week before her period, she can monitor the development of her follicles and the thickness of her uterine lining under the supervision of her doctor.