The Sex Organs - The Female Sex Organs

The Menstrual Cycle: The Three Phases of the Menstrual Cycle I

In scientific textbooks, the menstrual cycle is usually divided into two, three, four, or more different phases. For our present purposes, a division into three phases seems adequate.

The Three Phases of the Menstrual Cycle
(Seen as beginning after the last day of menstruation)
 

1. Preparing for Ovulation The endometrium begins to grow after menstruation.
2. Preparing for Implantation The endometrium is becoming ready for the implantation of a blastocyst.
3. Menstruation If no implantation occurs, the endometrium breaks down and is discharged in menstruation.

Key: A. Endometrium B. Cervical mucus plug C. Detached endometrium being discharged D. Unplugged area.