Hi!
Such a great topic to tackle!
So the menstrual cycle is divided into follicular phase and luteal phase.
Ovulation usually occurs about 14 days before menstruation (but the date varies of course).
A study conducted on women with type 1 diabetes , with continuous glucose monitoring, showed that there seems to be a difference in control between the follicular and luteal phases, and this is probably due to a hormonal effect. Additionally, ladies who have PMS during the luteal phase leading them to eat more may also demonstrate hyperglycemia due to increased caloric intake - usually increases carbs.
That‘s why insulin requirements could vary according to the cycle’s phase, and this should be taken into account while managing glucose control.