Structure of the reproductive system and age periods
Normal functioning of the female body is ensured by the ovaries, uterus, and neurohumoral regulation mechanisms. The time boundaries of age stages are conventional and depend on climatic features, ethnicity, and living conditions.
The following periods are distinguished:
- Intrauterine period and newborns (up to 1 year).
- Childhood (up to 7–8 years).
- Puberty (prepubertal period up to 14 years and pubertal period up to 17 years).
- Childbearing or reproductive period (up to 40–45 years).
- Perimenopause, premenopause, menopause, and postmenopause.
Establishment of menstrual function
The first menstruation (menarche) occurs at the age of 10–12 years and can happen either before or after the maturation of the oocyte. Regularity is established immediately or within a year and a half.
Temporal parameters of menstruation:
- Duration of discharge: 3 to 7 days.
- Volume of blood loss: 40–60 ml.
- Cycle counting: the 1st day of menstruation is considered the 1st day of the cycle.
Ovarian cycle and folliculogenesis
Cyclic changes divided into two phases occur in the ovaries. During the follicular phase, follicle growth and oocyte maturation take place, culminating in ovulation. In the second, luteal phase, the corpus luteum is formed at the site of the follicle.
At birth, a girl has about 2 million primordial follicles, but most of them undergo atretic changes. Normally, only one dominant follicle matures per cycle.
Rule of cycle numbers: a normal cycle lasts 21–35 days, discharge lasts 3–7 days, and normal blood loss amounts to 40–60 ml.
Class and exam questions
What is included in the female reproductive system?
The reproductive system includes the ovaries, the uterus, and neurohumoral regulation mechanisms.
When does full physiological readiness for gestation occur?
The appearance of menstruation does not mean immediate readiness for childbirth. Full readiness of the body is achieved at 17–18 years of age.
How many follicles remain in the ovaries by the time of menarche?
By the period of menarche, 200,000 to 400,000 primordial follicles remain in the ovaries.
What else to study on this topic
- Detailed analysis of folliculogenesis stages from the primordial to the dominant follicle
- Mechanisms of premenopause and postmenopausal involution of the body
- Characteristics and risks of the young primipara category
- Alternative methods of menstrual cycle tracking based on ovulation
- Embryo implantation processes and the role of the endometrium
Master the entire topic in the "Obstetrics and Gynecology" course
This is a summary. The course covers everything tested in classes and exams.
- Comprehensive study guide on the topic «Anatomy of the Female Genital Organs» and 973 other pages of the subject
- Assignments and quizzes after every topic — just like in a colloquium
- AI tutor answers questions on the topic anytime
- 21 video lessons on the subject
Other topics in the "Obstetrics" section
Prepared by WhiteCoat Pro faculty in accordance with the medical school curriculum. For educational purposes only.