Assisted Reproduction Topic 8

Assisted Reproduction What is assisted reproduction? Assisted reproduction is when medical procedures are used in order to ensure that the fertilization of an ovum by a spermatozoon occurs. What is it used for? Assisted reproduction may help couples that are either infertile or sterile conceive a child. 

Some Terms Infertility This term is attributed to couples that have been trying, without success, to become pregnant for a minimum of a year. The term infertility implies that the couple are having difficulty conceiving, but not necessarily unable to.  Sterile This term is attributed to a person that is unable to conceive a child or a man whose sperm are unable to fertilize an ovum.

Reasons for Infertility or Sterility Some causes for infertility or sterility are: Problems relating to ova or sperm production, such as the quality or quantity of gamete production. Anatomical malformations (problems related to anatomy of the reproductive system). Untreated sexually transmitted infections (STIs). However, very often the infertility of a couples cannot be explained. http://www.videojug.com/interview/infertility-basics-2 - parts 1, 2, 4, 5, 12, 13 http://www.videojug.com/interview/infertility-treatment-basics-2 - parts 2, 3

A step back in time… 1880s – the first fertilizations using sperm from a donor 1960s – the first children who were the result of fertilization with frozen sperm were born 1969 – the first fertilization of an ovum in the laboratory 1978 – the birth of the first test-tube baby (a child that was born from the fertilization of an ovum by sperm in the laboratory)

The Different Processes Before couples can receive an assistance with reproduction, they are assessed by a doctor to determine the cause and nature of their infertility. Once the doctor has a good idea of the situation, he/she can propose a treatment. The main treatments are: Hormonal treatments Artificial insemination In vitro fertilization Intracytoplasmic sperm injection

Hormone Treatments Hormones can be taken by women to trigger ovulation or to stimulate the growth of the follicles (layer of cells surrounding the oocyte). A doctor monitors the amount of hormones that a woman takes because sometimes taking hormones can result in the release of more than one ovum per cycle. An ultrasound can be used to determine the number of developing follicles.

Artificial Insemination This process involves the injection of spermatozoa directly into the uterus. This allows for fertilization to take place inside of the uterus (in vivo). Artificial insemination is recommended when the quantity of the man’s sperm is low or they are malformed. The steps are as follows: The woman receives hormones to stimulate ovulation to occur at a specific time. The sperm from the male or a donor is washed; only the healthiest sperm are used. The sperm are deposited directly in the uterus using a catheter on the day of ovulation in order to maximize the chance of fertilization.

In vitro Fertilization The woman receives hormone treatments to causes the ovaries to produce a large quantity of ova. Sperm is collected and washed, in order to obtain the best sperm. When ovulation occurs, all of the ova that were produced are collected. The sperm (a minimum of 50 000 per ovum) and ova are put together in a test tube or petri dish. The embryos are permitted to divide and grow in this environment for a couple days. Two days after fertilization has occurred, the best ovum (the one with the greatest chance of resulting in a full-term pregnancy) is selected. Using a catheter, the embryo is implanted in the uterus (in Quebec, they currently only implant 1-2). The remaining embryos are frozen and may be used for future implantations. This process involves the fertilization of the ovum by the sperm in the lab. This procedure is recommended when artificial insemination does not work or when a woman has blocked fallopian tubes. The steps for in vitro fertilization re as follows:

Intracytoplasmic Sperm Injection This procedure may be necessary for couples where the male produces only a small quantity of normal sperm and fertilization of the ova in unlikely even if in vitro is attempted. This process requires the ova to be directly injected with a spermatozoon. Once the injection takes place and the embryos begin to develop, they can be placed into the uterus with a catheter.