Hormones and Reproduction

• What role do hormones play in human reproduction?

  They control various reproductive functions
• What do sex hormones cause during puberty?

  Development of secondary sexual characteristics
• What is the main female sex hormone?

  Oestrogen
• What happens to eggs in females at puberty?

  They begin to mature and be released
• What is the process called when eggs are released in females?

  Ovulation
• What is the main male sex hormone?

  Testosterone
• Where is testosterone produced?

  In the testes
• What does testosterone stimulate in males?

  Sperm production
• How does sperm production differ between men and women after puberty?

  Men produce sperm continuously, women have a cycle
• What is the monthly cycle of events in women called?

  The menstrual cycle
• What other hormones are involved in a woman's menstrual cycle?

  Several hormones are involved
• How many hormones are involved in the control of the menstrual cycle?

  Four hormones
• What does FSH stand for?

  Follicle stimulating hormone
• What is the role of FSH in the menstrual cycle?

  Causes eggs to mature and stimulates oestrogen production
• Where is FSH produced?

  Pituitary gland
• What effect does oestrogen have on FSH and LH?

  Inhibits FSH release and stimulates LH release
• What is the function of oestrogen in the menstrual cycle?

  Makes the lining of the uterus grow again
• What does LH stand for?

  Luteinising hormone
• What is the role of LH in the menstrual cycle?

  Stimulates the release of the egg from the ovary
• Where is LH produced?

  Pituitary gland
• What is the role of progesterone in the menstrual cycle?

  Maintains the lining of the uterus
• Where is progesterone produced?

  Empty follicle in the ovaries
• What is the effect of progesterone on FSH and LH?

  Inhibits both FSH and LH release
• What are the four hormones involved in the control of the menstrual cycle and their functions?

  • FSH: Causes egg maturation and stimulates oestrogen production
  • Oestrogen: Inhibits FSH, stimulates LH, grows uterine lining
  • LH: Stimulates egg release from the ovary
  • Progesterone: Maintains uterine lining, inhibits FSH and LH
• What can reduce fertility?

  A variety of methods of contraception
• What are the hormonal methods of contraception?

  • Oral contraceptives (combined pill)
  • Contain oestrogen and progesterone
  • Inhibit FSH production
  • Prevent egg maturation and release
  • Injection, implant, or skin patch
  • Slow release of progesterone
  • Stops eggs from maturing and being released
• What do oral contraceptives contain?

  Oestrogen and progesterone
• How do oral contraceptives affect FSH production?

  They inhibit FSH production
• What is the purpose of an injection, implant, or skin patch in contraception?

  To stop eggs from maturing and being released
• What are the non-hormonal methods of contraception?

  • Barrier methods (condoms, diaphragms)
  • Prevent sperm from reaching an egg
  • Intrauterine devices
  • Prevent embryos from implanting in the uterus
  • Spermicidal creams
  • Kill or disable sperm
  • Surgical methods
  • Male and female sterilization
  • Cutting sperm ducts or tying fallopian tubes
• What do barrier methods of contraception do?

  Prevent sperm from reaching an egg
• What is the function of intrauterine devices?

  Prevent embryos from implanting in the uterus
• What do spermicidal creams do?

  Kill or disable sperm
• What are surgical methods of contraception?

  Cutting sperm ducts or tying fallopian tubes
• What concerns do some people have about contraception?

  Religious and ethical concerns
• Key Point

  Both contraception and fertility treatment are technological applications of science that raise ethical issues. People have many different views on these treatments.
• Key Point

  . Many decisions require the evaluation of the risks and benefits, e.g. there are risks with being pregnant

  . All decisions have to take into account the evidence as well as the arguments for and against
• What hormones may be given in a fertility drug?

  FSH and LH
• Why might doctors prescribe FSH and LH to a woman?

  If her FSH level is too low
• What are the steps involved in in vitro fertilisation (IVF) treatment?

  1. Administer FSH and LH to stimulate egg growth
  2. Collect eggs from the woman
  3. Fertilize eggs with sperm in the laboratory
  4. Insert one or two embryos into the uterus