Module 4 Lesson 5 - 3
Lesson 5 — Reproductive Technologies
Rhesus Factor
Read page 297 and examine figure 8.31
Rhesus factor is a protein on the red blood cells (RBCs). If the RBCs have rhesus factor proteins on the surface, the blood is Rh+ (positive), and if it does not, it is Rh- (negative).
Individuals with Rh- blood do not have antibodies to the Rh factors unless they are exposed to Rh+ blood. During pregnancy, the baby’s blood does not cross the placenta, but during parturition, some can cross into the mother’s bloodstream. When the Rh- mother is exposed to the baby’s Rh+ blood, the mother’s immune system begins to produce antibodies that can attack Rh+ blood.
This is not a problem for the first pregnancy because the baby will be born before a significant amount of antibodies can be produced by the mother’s immune system. However, if the second child is also Rh+, the mother’s antibodies will cross the placenta and attack the baby’s red blood cells.
In the event of an Rh incompatibility, an anti-Rh antibody is given to a mother within 72 hours of childbirth to prevent Rhesus factor antibodies from forming. The anti-Rh antibodies in the injection attack any of the baby's red blood cells that have crossed into the mother's blood before these cells can stimulate her immune system to produce her own antibodies. This procedure will not help if the woman has already begun to produce antibodies. Thus, the timing of the injection is crucial.
What can be done with the umbilical cord?
Read page 527
The umbilical cord and the placental blood contains blood stem cells. Unlike the embryonic stem cells at the morula or blastocyst stage, the blood stem cells are not totipotent. However, they are multipotent as they have shown to be able to grow into many cells such as bone marrow cells, blood cells, or nerve cells. Therefore, blood stem cells have the ability to treat some diseased related to blood or the immune system.
Many parents choose to save the baby’s umbilical cord blood in a private cord blood bank. However, if the baby already has the disease, the cord blood will not be able to help them. Also, the amount of cord blood is too small to treat an adult. If the baby has siblings with blood-related illnesses, the cord blood could help treat their diseases.
Some parents choose to donate the baby’s umbilical cord blood to a public cord blood bank. This blood can be used to treat another child who needs a stem cell transplant or for stem cell research. The cord blood stem cells differ from adult bone marrow stem cells and are less likely to be rejected by the recipient.
Try This
Work by yourself, or in a group, to complete Thought Lab 15.2: Evaluating Reproductive Technologies: Safety and Effectiveness on page 533 of your textbook.
Summarize findings for all the technologies investigated.
Thought Lab 15.2: Evaluating Reproductive Technologies: Safety and Effectiveness
Answers to Analysis and Extension Questions
- You could list factors such as mother's health, health and survival of the fetus, father's health, long-term effects, optimum conditions required, or failure/success rates. Assessment of risk may include long-term health of the mother or likelihood of the fetus surviving or being disabled in some way.
- Arguments should reflect the relevant definitions that have been chosen, and they should consider the priorities chosen or agreed upon.
- Other factors could include accessibility, ease of use, cost, social attitudes, cultural or religious taboos, partner's preferences, and permanence of method.
Self-Check
- What are two causes that can lead to male infertility? Identify two possible treatments for male infertility.
- What are two causes that can lead to female infertility? Identify two possible treatments for female infertility.
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Identify one of the best methods in preventing conception and protecting against transmission of STIs.
Self-Check Answers
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Cite any two of the following reasons for male infertility: obstructions in the vas deferens or epididymis, low sperm count, high proportion of abnormal or non-viable sperm, inability to achieve an erection or ejaculation, smoking,
alcohol use, overheated testicles. Treatments can include healthier lifestyle (cutting back on smoking, alcohol, wearing looser clothing), artificial insemination, in vitro fertilization, or use of a sperm bank.
- Cite any two of the following reasons for female infertility: blocked Fallopian tubes, failure to ovulate, endometriosis, or damaged eggs. Treatments can include artificial insemination, in vitro fertilization, surrogate mothers, or superovulation.
- The technology that does the best job of preventing conception and protecting against the transmission of STIs is a combination of condoms (a physical barrier) and chemical barriers (spermicides in the form of jellies, foams, or creams).
Inquiry into Biology (Whitby, ON: McGraw-Hill Ryerson, 2007), TRM Pg 530. Reproduced by permission.
Reflect and Connect
The opinions surrounding reproductive technologies are, as with most things in life, based on individuals' experiences and exposures to the issue in question. In North America, no restraints are placed on the number of children one family can have. In
1979, China implemented a 'one child policy' to try to restrict the growth of the country's population. Chinese families were expected to have only one child, which the government believed would alleviate social and environmental problems. The
Chinese government reviewed this policy in 2013 and decided to overturn the implementation of the 'one child policy'. Now, the policy allows two children per family.
Write a reflection of how this policy would affect your family (present and future) and our society if it were implemented in Alberta. How would this policy be followed or enforced? What are the reproductive technology implications resulting from such a policy? Should families be taxed based on the number of children they have? This is based on the assumption that the effect of a family with more children would be greater on society and the environment than a family with fewer children.
Every individual and every couple must make the final decision of the extent of their involvement with reproductive technology. Not only are the ethical and moral issues important to consider, but the cost of treatments such as IVF can be approximately $12,000/treatment, thereby making this option unaffordable to some couples.
Going Beyond
Reproductive technologies always bring with them controversy, ethical and moral issues that present pros and cons to their use. What do you believe are the ethical and moral issues on the use of reproductive technologies? What have governments done in Canada to deal with the concerns over the use of reproductive technologies?
First, research any government legislation or policies in Canada or any other country that deal with the use of reproductive technologies. Then, compare those that you find.
Ethical and moral issues are often included on the Diploma Examination. Be prepared to support your stand on an issue.
Throughout history, humans have been trying to control their reproductive potential. Reproductive technologies first began as attempts to prevent pregnancy and now have evolved into extremely advanced reproductive enhancement and reduction prevention techniques. Reproductive technologies have advanced to allow the monitoring of embryonic and fetal development, and scientists and doctors have developed the technology and skill to enable them to complete some fetal surgeries successfully.
Developed countries are fortunate to have continued the advancement and use of technologies to include those that assist in parturition. However, in developing countries, the advances in technology have not been seen. Maternal mortality rates vary. In South Sudan, one in 49 women dies in childbirth; in Canada, that ratio is one in 8300. These figures do not take into account the numbers of fetal deaths.
The development and use of, and often the need for, reproductive technologies have advanced significantly. However, the ethical and moral debates on the practise and use of reproductive technologies continues, whether it is concern for equal access to safe childbirth or other issues.