Controlling Fertility Flashcards
What is fertility?
Fertility is the ability of an individual to conceive young or a child.
What are the two types of fertility/fertile periods
Continuous Fertility (Males) and Cyclical Fertility (Females)
Explain what is meant by continuous fertility
Applies to men, able to continuously produce sperm in their seminiferous tubules.
Explain what is meant by cyclical ferility
-Applies to women, only fertile for a few days during each menstrual cycle.
-Leads to women having a fertile period (around the day of ovulation, around day 14)
- After ovulation, the female ova is only viable for 1-2 days.
How can fertile periods in females be calculated/identified?
Temperature - A woman’s temperature increases by around 0.5°C after ovulation - indicates the start of her fertile period.
Cervical Mucus - A woman’s cervical mucus becomes thin and watery after ovulation, this allows the mucus to be more easily penetrated by sperm, increasing the chance of successful fertilisation.
To who is identifying/calculating fertile periods in females useful to?
Couples who wish to conceive a child may track fertility periods to increase the chance of successful fertilisation during intercourse.
What is infertility
Infertility is a disease of the reproductive system defined by the failure to achieve a clinical pregnancy after 12 months or more of regular unprotected sexual activity.
What are examples of treatments of infertility?
1) Stimulating Ovulation
2) Artificial Insemination
3) Intracytoplasmic Sperm Injection (ICSI)
4) In Vitro Fertilisation
What is artificial insemination ?
A treatment of infertility
-Several samples of semen are collected, over a period of time, and introduced into the female reproductive tract by means other than sexual intercourse (injection).
-Is particularly useful where the male has a low sperm count.
-If a partner is sterile a donor may be used to provide semen.
What is stimulating ovulation ?
A treatment of infertility - either the use of drugs which:
1) mimic the action of FSH and LH
2) prevent the negative feedback effect of oestrogen on FSH production so that ovulation can happen easier.
It is also used for IVF programmes
What is intracytoplasmic sperm injection (ICSI) ?
A treatment of infertility
-Involves drawing the head of a healthy sperm into a needle and injecting it directly into the ova to achieve fertilisation.
-Useful if sperm are low in number or defective (cant swim)
It is also used as a part of IVF programmes.
What is In vitro fertilisation ?
A treatment of infertility
-Fertilisation between an ova and sperm outside of the female body.
-Useful if the male has a low sperm count or the female has a blocked oviduct.
What are the stages of in vitro fertilisation?
1) Women is given hormone treatment to stimulate egg production (superovulation)
2) Multiple ova are taken from the women’s ovaries using a surgical procedure.
3) In the lab, the ovum are mixed with the man’s sperm cells, in a culture dish to become fertilised.
4) The fertilised eggs, or embryos, are placed in an incubator for about 48 hours, until they have formed at least eight cells.
5) Embryos are implanted in the women’s uterus or frozen for future implantation.
What is pre-implantation Genetic Diagnosis (PGD) ?
Before implanting the selected fertilised ova into the female they may be tested for genetic abnormalities - these methods allow experts to identify single gene disorders and chromosomal abnormalities.
Used in IVF
What is contraception ?
-The intentional prevention of conception or pregnancy, by natural or artificial means.
-Contraception is based on the biology of fertility
-Contraception methods rely on us understanding when males/females are fertile (when conception can occur)
