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Page 1: Sex selection and or prediction
Page 2: Sex selection and or prediction

is the attempt to control the sex of the offspring to

achieve a desired sex. It can be accomplished in several ways, both pre- and post-implantation of an embryo, as well as at birth. It has been marketed under the title family balancing.

Sex selection

Page 3: Sex selection and or prediction

Methods

Page 4: Sex selection and or prediction

Two major types of pre-implantation methods can be

used for social sex selection. Both of them are based on actively rendering the second sex chromosome to be either a Y chromosome (resulting in a male), or an X chromosome (resulting in a female).

Pre-implantation

Page 5: Sex selection and or prediction

The Ericsson method, first applied in a clinical

setting in the 1970s by Dr. Ronald J. Ericsson, uses higher concentrations of sperm of the desired sex to increase the likelihood ofconceiving that sex. The method has a 70-72% success rate for boys and a 69-75% success rate for girls.[15] Currently, approximately 50 gender selection centers in the United States use the Ericsson Method for artificial gender selection.[16]

The Ericsson method

Page 6: Sex selection and or prediction

Multiple eggs are removed from the mother. The

eggs are fertilized in the laboratory using the father's sperm in a technique called in vitro fertilization (IVF). "In vitro" is Latin for "within glass". Fertilized eggs are called embryos. As the embryos develop through mitosis, they are separated by sex. Embryos of the desired gender are implanted back in the mother's uterus.

Prior to fertilization with IVF, the fertilized eggs can be genetically biopsied with preimplantation genetic diagnosis(PGD) to increase fertilization success

IVF/PGD technique

Page 7: Sex selection and or prediction

first formally theorized in the 1960s by Landrum B.

Shettles, proposes that sperm containing the X (female) chromosome are more resilient than sperm containing the Y (male) chromosome. The method advocates intercourse two to four days prior to ovulation. By the time ovulation occurs, the cervix should contain a higher concentration of female sperm still capable of fertilization (with most of the male sperm already dead). Intercourse close to ovulation, on the other hand, should increase the chances of conceiving a boy since the concentration of Y sperm will be higher at the height of the menstrual cycle.

The Shettles method

Page 8: Sex selection and or prediction

is an "intercourse timing" method that advocates the

opposite of the Shettles method. The Whelan method suggests intercourse four to six days prior to ovulation to increase likelihood of fertilization by male sperm.

The Whelan method

Page 9: Sex selection and or prediction

Sperm sorting is an advanced technique that sorts sperm "in vitro" by flow cytometry. This shines a laser at the sperm to distinguish X and Y chromosomes, and can automatically separate the sperm out into different samples.

Sperm sorting

Page 10: Sex selection and or prediction

Sex selection after implantation can be performed by prenatal sex discernment, followed by sex-selective abortion of any offspring of the unwanted sex. For prenatal sex discernment, a blood test can be taken from the mother for testing of small amounts of fetal DNA within it, and has been estimated to be reliable more than 98% of the time, as long as the samples are taken after the seventh week of pregnancy

Post-implantation

Page 11: Sex selection and or prediction

Sex-selective infanticide - Killing children of the

unwanted sex. Though illegal in most parts of the world, it is still practiced.

Sex-selective child abandonment - Abandoning children of the unwanted sex. Though illegal in most parts of the world, it is still practiced.

Sex-selective adoption - Placing children of the unwanted sex up for adoption. Less commonly viewed as a method of social sex selection, adoption affords families that have a gender preference a legal means of choosing offspring of a particular sex.

Post-birth

Page 12: Sex selection and or prediction

PGD gender selection is the most reliable method for gender selection, approaching 100% accuracy (although, of course, there are always possibilities for technical errors).

Page 14: Sex selection and or prediction

In contrast, primary care physicians questioned

whether women could truly express free choice under pressure from family and community.[41] In addition, primary care physicians voiced the concerns that sex selection led to invasive medical interventions in the absence of therapeutic indications, contributed to gender stereotypes that could result in child neglect of the lesser-desired sex, and was not a solution to domestic violence.[41]

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When gender selection is used to prevent a genetic disease, the process is called "medical gender selection." In some cases, the so-called "sex-linked diseases" are inherited via the mother but only male offspring are affected (muscular dystrophy, hemophilia, etc.).

Page 16: Sex selection and or prediction

In other cases, conditions are more severely expressed in one gender (Fragile X syndrome, autism in males, etc.) than the other. Medical reasons for gender selection can, however, also be psychological: a single female may feel better equipped having a daughter than a son; parents who lost a child may feel a strong need for a child of the same gender.

Page 17: Sex selection and or prediction

There are only two techniques that reliably affect gender: One is PGD with In Vitro Fertilization (IVF) , and the other is an experimental sperm-sorting technique, called Microsort.

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Sex selection is officially prohibited in China, but the Chinese government admits that the practice is widespread, especially in rural areas of China and among lawless groups such as ghettoized migrant workers in cities (despite denials by the government-sponsored studies).

Legality

Page 19: Sex selection and or prediction

Social sex selection is illegal in India.[61] To ensure this, prenatal determination of sex through ultrasound is also illegal in India. These laws are instituted to combat the prevalent practice of sex-selective abortion. However, these laws have generally failed to be effective in rural areas and, despite education efforts, sex-selective abortion continues to be widely practiced there.

Legality

Page 20: Sex selection and or prediction

Sex selection is legal in most of the world, and it is

practiced particularly in Western countries, but is more limited in Eastern countries, such as India or China. There is fertility tourism from the United Kingdom[62] and Canada[61] to the United States for sex selection, because preimplantation genetic diagnosis (PGD, a potential expansion of IVF), which can be used for sex selection, is prohibited in the UK and Canada, except when it is used to screen for genetic diseases, while the laws in the US are more relaxed in this subject.

Legality