Controlling fertility

Question 1

Continuous fertility

Answer 1

Men continuously produce sperm in the semineferous tubules in the testes

Question 2

Cyclical Fertility

Answer 2

Women show cyclical fertility as the they are only fertile for a few days during each menstrual cycle leading to a fertile period.

Question 3

Identification of the fertile period

Answer 3

-A woman’s temperature increases by around 0.5 degrees after ovulation
-The fertile period lasts for about 1-2 days
-Temperature remain high during luteal phase

Question 4

Cervical Mucus

Answer 4

After ovulation, her cervical mucus becomes thin and watery, making it more easily penetrated by sperm, increasing the chance of achieving fertilisation.

Question 5

Who may find the Cervical Mucus Indicators
useful and why?

Answer 5

Couples who wish to have a child and want to know when sexual intercourse is most likely to achieve fertilisation.

Question 6

Is calculation of the fertile period a reliable method of contraception?

Answer 6

No because cycle period varies from one individual to another.

Question 7

Infertility

Answer 7

Disease of the reproductive system defined by the failure to achieve pregnancy after 12 months or more of regular unprotected sexual activity.

Question 8

Treatments of of Infertility

Answer 8

Stimulating Ovulation
Artificial Insemination
Intracytoplasmic sperm injection(ICSI)
In vitro fertilisation
Pre-implantation genetic diagnosis(PGD)

Question 9

Stimulating Ovulation Drugs

Answer 9

-Drugs that mimic the normal action of FSH(development of a follicle) and LH(ovulation)
-Drugs that prevent the negative feedback effect of oestrogen on FSH secretion

Question 10

Effect of Stimulating Ovulation Drugs

Answer 10

Ovulatory drugs that mimic the action of FSH and LH can cause “super ovulation” that can result in multiple births or be used to collect ova for in vitro fertilisation (IVF) programmes.

Question 11

Artificial Semination

Answer 11

-Introduction of sperm into the female reproductive tract by some means other than sexual intercourse
-Several samples of semen are collected over a period of time.
-Artificial insemination is particularly useful where the male has a low sperm count.
-If a partner is sterile a donor may be used to provide semen.

Question 12

Intracytoplasmic sperm injection(ICSI)

Answer 12

-This involves drawing the head of a healthy sperm into a needle and then injecting the head of the sperm directly into the egg to achieve fertilisation.
-Used if sperm are defective or low in number.
-Commonly used in IVF programmes

Question 13

In vitro fertilisation

Answer 13

-Fertilisation of egg and sperm occurs outside the female body in a culture/petri dish
-Often used when males have low sperm count or females have blocked uterine tubes

Question 14

Stages of In Vitro Fertilisation

Answer 14

-women receives drugs to stimulate ovulation(hormone stimulation)
-surgical removal of eggs from ovaries after hormone stimulation
-Eggs are mixed with sperm in a culture dish
-The fertilised eggs(zygote) are incubated when they have formed at least 8 cells.
-the fertilised eggs are then transferred to the uterus for implantation

Question 15

Pre-implantation genetic diagnosis(PGD)

Answer 15

Before implanting the selected fertilised egg into the female they may be tested for genetic abnormalities, which allows experts to identify single gene disorders and chromosomal abnormalities.

Question 16

Contraception

Answer 16

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

Question 17

Artificial methods of contraception

Answer 17

physical(barrier) or chemical

Question 18

Physical methods of contraception are

Answer 18

1. Barriers
   2.Intra-uterine devices
   3.Sterilisation procedures

Question 19

Barrier methods

Answer 19

make use of a device that physically block the ability of sperm to reach an ovum.
These include:-
Condom
Diaphragm
Cervical cap

Question 20

Intra-Uterine device

Answer 20

T shapes structure which fits into the uterus for months even years preventing implantation of embryo

Question 21

Sterilisation Procedures are

Answer 21

Vasectomy and Tubal ligation

Question 22

Vasectomy

Answer 22

Cutting and tying the sperm ducts preventing the release of sperm during sexual activity.

Sperm produced after this procedure are usually destroyed

Question 23

Tubal Ligation

Answer 23

Cutting and tying the oviducts preventing an egg meeting the sperm and reaching the uterus.

Sterilisation is a highly effective method of contraception, but it is normally irreversible.

Question 24

Chemical methods of contraception are

Answer 24

1. The oral contraceptive pill(the combined pill)
2. The progesterone only pill(the mini pill)
3. The morning-after pill(emergency)

Question 25

The oral contraceptive pill(the combined pill)

Answer 25

-The “pill” contains a combination of synthetic progesterone and oestrogen that mimics negative feedback
-This prevents the release of FSH and LH from the pituitary gland
-Pills usually taken for 3 weeks/one pill taken each day

Question 26

The progesterone only pill(the mini pill)

Answer 26

-Contains progesterone only and no oestrogen. They work by thickening the cervical mucus.
-This reduces the viability of sperm and their access to the uterus.

Question 27

The morning-after pill(emergency)

Answer 27

The “pill” contain higher doses of progesterone and oestrogen. Taken by a woman after unprotected sexual intercourse. Ideally these should be taken as soon after unprotected sex as possible.
It prevents: -
Ovulation (if an egg has not already been released).
Implantation (from occurring if fertilisation has taken place unintentionally).