2.3 - The Biology Of Controlling Fertility

Question 1

What is fertility?

Answer 1

Fertility is ability to conceive children.

Question 2

What type of fertility do men show?

Answer 2

Main continuously produce sperm in their testis so show continues fertility.

Question 3

What type of fertility do women show

Answer 3

Women show cyclical fertility, leading to a fertile period which lasts a few days during each menstrual cycle.

Question 4

What changes happened to woman after ovulation?

Answer 4

A woman’s body temperature rises by around 0.5°C after ovulation and her cervical mucus becomes thin and watery.

Question 5

What are infertility treatments and contraception based on?

Answer 5

Infertility treatments and contraception are based on the biology of fertility.

Question 6

What percentage of couples become pregnant in the first year?

Answer 6

84% of couples will conceive naturally within 1 year of having regular, unprotected intercourse.

Question 7

Percentage chance of pregnancy after 3 years

Answer 7

Couples who have been trying to conceive for more than 3 years without success have a 25% chance of becoming pregnant naturally within the next year.

Question 8

Infertile meaning

Answer 8

Someone who is infertile has difficulty conceiving a child

Question 9

Infertility treatments

Answer 9

Fertility drugs which stimulate ovulation

Artificial insemination

Intra-cytoplasmic sperm injection

In vitro fertilisation

Question 10

What can be a cause of female infertility

Answer 10

Female infertility can be due to failure to ovulate

Question 11

How can ovulation be stimulated?

Answer 11

Ovulation can be stimulated by drugs that prevent the negative feedback effect of oestrogen on FSH secretion.

Question 12

How are other ovulation drugs used?

Answer 12

Other ovulatory drugs mimic the action of FSH and LH. These drugs can cause super ovulation.

Question 13

What is super ovulation

Answer 13

Super ovulation is the production and release of multiple ova per menstrual cycle that can result in multiple births or be used to collect ova for IVF programmes.

Question 14

When is artificial insemination useful?

Answer 14

Artificial insemination is useful when a male has low sperm count.

Question 15

Artificial insemination process

Answer 15

Several samples of semen are collected over a period of time.

Sperm are placed inside the uterus near an oviduct using a catheter.

Question 16

What happens is the male partner is sterile?

Answer 16

If the male partner is sterile (not producing gametes), sperm from a donor can be used. This is called donor insemination.

Question 17

When is intracytoplasmic sperm injection used?

Answer 17

If mature sperm are defective or very low in numbers ICSI can be used.

Question 18

Intracytoplasmic sperm injection (ICSI) process

Answer 18

The head of the sperm is drawn into a needle and injected directly into the egg to achieve fertilisation.

Question 19

What does in vitro refer to?

Answer 19

In vitro refers to the manipulation of organs, tissues and cells in a controlled artificial environment.

Question 20

What do hormonal treatments stimulate

Answer 20

Hormonal treatments stimulates the development of multiple follicles

Question 21

In vitro fertilisation treatment

(IVF) process

Answer 21

Ova are surgically removed from the ovaries using a hollow needle and then mixed with sperm in a culture dish.

The zygotes are then incubated until they have formed at least 8 cells and are then transferred to the uterus for implantation.

Question 22

How can IVF be used in conjunction with pre-implantation genetic screening?

Answer 22

IVF can be used in conjunction with pre-implantation genetic screening to identify genetic disorders and chromosome abnormalities.

Question 23

What does pre-implantation genetic screening tests ensure?

Answer 23

It ensures the most suitable embryos for insemination and implantation.

Question 24

Contraception definition

Answer 24

The intentional prevention of conception or pregnancy by natural or artificial means.

Question 25

What groups can contraception be organised into?

Answer 25

Contraception can be organised into 2 groups

• physical
• chemical

Question 26

How do Physical methods of contraception work

Answer 26

Physical methods of contraception physically prevent fertilisation or embryo implantation.

Question 27

What do physical methods of contraception include?

Answer 27

Barrier methods

Avoiding fertile periods

Intra-uterine devices

Sterilisation

Question 28

How do barrier methods of contraception work?

Answer 28

Barrier methods use a device to physically block sperm from reaching the ovum therefore preventing pregnancy.

Question 29

Examples of barrier methods of contraception

Answer 29

Male condom

Female condom

Diaphragm

Cervical cap

Question 30

What is an intra-uterine device (IUD)

Answer 30

An IUD is a small T-shaped plastic and copper device that is inserted into the uterus.

Question 31

How does an intra-uterine device (IUD) work and how effective are they

Answer 31

The IUD releases copper and prevents pregnancy for between 5 to 10 years. They are more than 99% effective at preventing pregnancy.

Question 32

What is sterilisation

Answer 32

Sterilisation as an operation to permanently prevent pregnancy.

Question 33

What does female sterilisation involve?

Answer 33

Female sterilisation involves cutting, tying or blocking the oviducts.

Question 34

What does male sterilisation involve?

Answer 34

Male sterilisation involves cutting, tying or blocking the sperm ducts.

Question 35

What is the oral contraceptive pill and how affective is it?

Answer 35

The oral contraceptive pill is a chemical method of contraception.

It is over 99% effective at preventing pregnancy.

Question 36

What does the oral contraceptive pill contain

Answer 36

The oral contraceptive pill contains a combination of synthetic oestrogen and progesterone.



Question 37

What do the synthetic hormones in the oral contraceptive pill do

Answer 37

The synthetic oestrogen and progesterone hormones mimic negative feedback, preventing the release of FSH and LH from the pituitary gland.

Question 38

How does the oral contraceptive pill work

Answer 38

The oral contraceptive pill works by preventing ovulation. It also thickens the cervical mucus and thins the endometrium.

Question 39

What does the progesterone only pill cause

Answer 39

The progesterone only pill, also known as the mini pill, causes the thickening of the cervical mucus.

Question 40

What is the morning after pill and what does it do?

Answer 40

The morning after pill is a form of emergency contraception which prevents ovulation or implantation.