2.3 Biology Of Controlling Fertility Flashcards
Females have cyclical fertility
Fertile for 1-2 days following ovulation
Males have continuous fertility
Negative feedback control maintains a fairly high level of FSH & ICSH which allows testosterone to always secrete sperm
How can a woman calculate her fertile period?
Temp rise of 0.1-0.2 degrees Celsius
Thinner & watery vaginal mucus
Why may a woman fail to ovulate?
Failure to secrete FSH & LH
How can ovulation be stimulated if a woman fails to ovulate
Drugs which mimic actions of FSH & LH
What is artificial insemination?
The insertion of sperm into female tract using a syringe
When is artificial insemination useful
When a mans sperm count is low
If a partner is sterile a donors sperm can be used
When is IVF ( in vitro fertilisation) used
When infertility is caused by a blockage of oviducts
The stages of IVF
Women given hormone treatment to stimulate multiple ovulation
Several Eggs are removed from ovary using syringe
Eggs mixed with sperm in culture dish containing nutrient medium to allow fertilisation to take place
When is ICSI ( intracytoplasmic sperm injection ) employed
When a mans sperm count is low
Sperm are dead
Stages of ICSI are
Women given hormone treatment to stimulate multiple ovulation
Several Eggs are removed from ovary using syringe
Sperm are injected into an egg using a syringe in a culture dish
Eggs are incubated in nutrient medium for 1-3 days
Some are tested for genetic abnormalities
What is PGS ( pre-implantation genetic screening )
PGS is a non specific approach which checks the embryo for genetic disorders & chromosomal abnormalities
What is PGD ( pre implantation genetic diagnosis )
PGD is a specific approach used to check for a known chromosomal or gene defect
What is meant by contraception
Initial prevention of conception or pregnancy by natural or artificial means
Physical contraception methods include
- Barrier methods eg condom, diaphragm, cervical cap
- intra-uterine devices
- sterilisation procedures
- tubal ligation
