Female Reproduction

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Female Reproduction
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Female Reproduction
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Female Reproduction

• The most important part of the female
  reproductive system are the ovaries

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Two Functions of the Ovaries

• Production of ova
• Secrete hormones

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Primary Follicles

• At birth the ovaries contain many small sac like
  structures that contain immature ova called
  primary follicles

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Primary Follicles

• It is estimated that there are 200,000-400,00
  primary follicles in each ovary at birth

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Primary Follicles

• It is estimated that there are 200,000-400,00
  primary follicles in each ovary at birth
• By age 50 most of them have degenerated.

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Puberty

• At age 8 the pituitary gland sends hormonal
  messages to the ovaries, stimulating them to
  release estrogen into the circulatory system.

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Puberty

• Between the ages of 11-14 the hormonal message
  becomes stronger thus bringing about the
  physiological changes known as puberty.
• During this time the ovaries release estrogen
  into the circulatory system.

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Estrogen

• Estrogen is responsible for the primary and
  secondary sex characteristics.

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Primary Sexual Characteristics

• Increase in the size and physiological maturity
  of the fallopian tubes, uterus and vagina.

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Secondary sexual characteristics

• Sex desire
• Body hair growth
• Breast development
• Feminine body features
• Ovulation
• Menstruation

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Female Ovulation

• Each month 15-20 immature follicles begin to grow
  and develop, usually one of these will balloon
  outward to full maturity. This one is called the
  graafian follicle.

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Pituitary Gland

• Simultaneous with the development of the stigma
  the pituitary gland increases its output of LH
  (Luteinizing Hormone)

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Ovulation

• LH causes the stigma to rupture causing
  ovulation.
• Once ovulation has occurred the egg cell may be
  fertilized within 12-36 hours. After which it
  begins to degenerate.

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Ovulation

• The fallopian tubes gathers the egg by its
  fimbriated ends called ampulla and by the current
  created by the motion of the cilia.

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Ovulation

• Once ovulation has occurred the follicular
  remains are transformed into a temporary
  endocrine gland called the Corpus Luteum.

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Ovulation

• To prepare the reproductive system for the
  reception of the fertilized egg the corpus luteum
  secretes two important hormones estrogen and
  progesterone

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Hormones

• Estrogen and progesterone are responsible for
  preparing the female reproductive system for
  reception of the fertilized egg.

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Ovulation Proliferative Phase

• Initiated by estrogen causes a rapid growth of
  endometrial cells.

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Ovulation Secretory Phase

• Initiated by progesterone causing an increase in
  blood supply to the uterus
• Acting together these hormones build and maintain
  the endometrium anticipating the reception of the
  fertilized egg.

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Fertilization

• If fertilization occurs the endometrium grows to
  a thick, blood vessel-rich, tissue layer. This
  represents an optimal environment for the
  implantation of a fertilized egg upon its arrival
  in the uterus.

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Menstrual Phase

• If fertilization fails to take place phase three
  of this recurring cycle is initiated
• Menstrual Phase Approximately 24 hours prior to
  menstruation the blood supply to the uterus is
  shut off. In the absence of the blood supply the
  lining of the uterus endometrium dies. The dead
  tissue together with 1) a small quantity of blood
  in the uterine cavity initiates uterine
  contractions. These contractions expel the
  contents of the uterus as the menstrual flow.
• The menstrual flow last approximately 7 days
  after which the cycle starts again.