Reproduction

• Process of sex


  1. Penis is moved in and out of vagina

  2. Semen is then released into the vagina
• Main events of menstrual cycle

  1. Day 1-5/7: Bleeding starts as uterus lining breaks down and passes out of the vagina (period)

  2. Days 6-13: Egg cell starts to mature, uterus lining begins to build up again

  3. Day 14: Egg is released from ovary (ovulation)

  4. Days 15-17: Egg travels down oviduct towards uterus

  5. Days 15-27: Uterus lining will stay thick for a while waiting for the egg to be fertilized

  6. Day 28: If egg is fertilized, cycle stops + uterus lining stays thick. If not, cycle will start again
• FSH

  Stimulates the egg cells to develop in the follicles of the ovary
• LH


  Stimulates ovulation (of the MATURE egg)
• Fertilization in humans

  Involves the fusion of sperm and egg to produce a zygote
• Zygotes undergo to develop into an embryo

  Cell division
• Oestrogen

  Stimulates the lining of the uterus to build up
• Progesterone

  Stimulates growth of blood vessels in uterus, maintains thick uterus lining
• Full-term pregnancy has 3 trimesters and lasts around 40 weeks
• Placenta

  Provides oxygen + nutrients to the embryo, and it removes waste substances
• Safe sex involves contraceptions and protection from STI's
• Amniotic fluid

  Protects the developing embryo
• Correct use of condoms

  Unroll condom all the way down the penis, carefully remove and put in trash
• Contraceptive methods

  • Condoms
  • Diaphragms/caps
  • Pill
  • Injection
  • Sterilization
  • Natural planning
• Condoms

  Can protect against STI's, can rip/tear if used incorrectly
• Diaphragms/caps

  Can be put in place at convenient time before sex, less effective than most other forms of contraception
• Pill

  Can be used to manage heavy / painful / irregular periods, need to remember to take it everyday
• Injection

  Effective between 8 - 13 weeks, can take up to a year for fertility to turn back to normal
• Natural planning

  Increases self awareness of fertility, not suitable for everyone as different factors can disrupt fertility signals
• Sterilization

  Only has to be done once, not easy to reverse
• Most common STI's

  • Chlamydia
  • Gonorrhea
  • Syphilis
  • Genital herpes
  • HPV
  • HIV
  • Hepatitis
  • Pubic lice
  • Trichomoniasis
• Chlamydia

  Transmission: Infected people from person to person via sex or mother -> baby, Symptoms: Unusual discharge, bleeding, 50% of men + 75% of women have no symptoms, pain
• Gonorrhea

  Transmission: Unprotected oral, vaginal + anal sex, mother -> baby, Symptoms: Can spread to other parts, 10% of men + 50% of women dont have symptoms, green/yellow discharge, pain when urinating
• Syphilis


  Transmission: Unprotected oral, anal or vaginal sex, unwashed sex toys, mother -> baby, Symptoms: Initial are not vv serious, sore on penis/vagina, rash on palms/souls of feet, flu-like symptoms, weight loss, blindness, deafness, death
• Genital herpes

  Transmission: Mother -> baby, sexual contact, mouth to mouth / skin to skin contact, sharing sex toys, Symptoms: Pain during urination, discharge, flu-like symptoms, blisters (can burst), stinging around genitals
• HPV


  Transmission: Physical contact, sex, unwashed sexual toys, Symptoms: Small lumps around anus, itching around anus
• HIV

  Transmission: Bodily fluids of infected person, oral + vaginal sex, sharing needles, Symptoms: Flu-like symptoms (80% experience this), causes progressive damage to immune system
• Hepatitis


  Transmission: Oral sex, sharing needles, injected drugs, close physical contact, Symptoms: Swelling in legs, confusion, vomiting, joint pain, fever, darkening of urine
• Pubic lice


  Transmission: Human contact -> lice can only jump/crawl, sex, sharing towels/clothing, Symptoms: Itching in infected areas, swelling + irritation red spots, skin/eye problems
• Trichomoniasis

  Transmission: Vaginal sex, unwashed sex toys, Symptoms: Itching, swelling in inner thigh + penis/vagina, more urine
• Testes


  The male reproductive system produces sperm in the testes, which are two oval-shaped organs located in the scrotum
• Epididymis

  Once sperm are produced, they move to the epididymis, a coiled tube that sits on top of each testicle. Here, sperm mature and become capable of fertilizing an egg
• Vas deferens


  Mature sperm then travel through the vas deferens, a long tube that carries them from the epididymis to the urethra
• Prostate gland and seminal vesicles


  During sexual arousal, the prostate gland and seminal vesicles produce fluids that mix with sperm to create semen
• Urethra


  Semen travels through the urethra and exits the body through the penis during ejaculation
• Journey of sperm to reach the egg

  1. Cervix: The cervix is the opening to the uterus, and it can be a tough barrier for sperm to penetrate

  2. Uterus: Once sperm make it through the cervix, they have to swim through the uterus, which can be a challenging environment due to its muscular contractions

  3. Fallopian tubes: Finally, sperm have to navigate the fallopian tubes to reach the egg. This can be a long and winding journey, and only the strongest sperm will make it to the egg