Biology of controlling fertility

Treatment of infertility

Contraception

Fertile periods

  1. Artificial ovulation stimulation, this is where chemicals are used to mimic the actions and effects of the hormones FSH and LH these artificial hormones allow for eggs to mature and ovulation to occur helping fertility. These could also lead to super ovulation and therefore could lead to multiple births.
  1. Artificial insemination, this is where sperm are injected into the uterus bypassing the vagina allowing for a higher number of sperm surviving and therefore more chance of fertilisation.
  1. ICSI (intracytoplasmic sperm injection) this is where the cell body of a sperm is injected directly into the ova and therefore allows for an almost guaranteed chance of fertilisation. THis is used where the viablility of the ssperm is questionable.
  1. IVF (in vitro fertilisation) is where ova will be removed from the ovaries and cultured in a growth medium then the ova will be mixed with fertile sperm or ICSI will take place allowing for fertilisation to occur outside the body. The now fertilised egg is re-implanted into the mother where implantation into the endometrial lining will take place. the other ova are kept in cryostorage incase of retrial of the procedure.

Within males there is continuous fertility because the relatively constant levels of testosterone within the bloodstream there is a constant production of gametes

Within females the ovulation cycle is a monthly period and therefore we call this cyclical fertility

Physical

Chemical

OCP (oral contraceptive pill), this pill contains synthetic versions of Progesterone and oestrogen which inhibit the secretions from the pituitary

Morning after pill, this pill this contains extreme concentrations of progesterone and oestrogen and therefore causes quick stoppage of FSH and LH production and inhibits implantation. This also causes the cervical mucus to thicken.

Mini pill, this pill only contains progesterone and inhibits FSH and LH production. It also stops the thickening of the endometrium and therefore makes it much harder for iplantation

Tubual ligation, this is where the oviducts are severed and sealed preventing ova transferral

Intrauterine Device IUD, this is a copper or plastic device which prevents implantation

Cervical cap, a physical barrier between the oviducts and uterus preventing fertilisation

Diaphragm, a rubber dome inserted into the vagina to prevent fertilisation

vaesectomy, sperm ducts are cut and sealed to prevent sperm movement

Condom, a physical barrier preventing sperm reaching the vagina

Rhythm method, a natural method of avoidal of fertile periods