Sex selection


 * This article is about the selection of the sex of offspring. For the evolutionary concept, see sexual selection

Parents frequently prefer their offspring to be of a particular sex for a variety of reasons. Social sex selection or human sex selection is the attempt to control the sex of 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.

Pre-implantation methods
Two major types of pre-implantation methods can be used for social sex selection.

Sperm sorting - The separation of X Chromosome sperm from Y Chromosome sperm. The resulting sorted sperm are used in either artificial insemination or in-vitro fertilization (IVF) procedures.

Preimplantation genetic diagnosis (PGD) - In sex selection cases, embryos resulting from IVF procedures are genetically tested for X or Y Chromosomes. The embryos of the desired sex are then implanted.

Post-implantation methods
Prenatal diagnosis - Amniocentesis and/or ultrasound is used to determine sex of an offspring, leading to subsequent abortion of any offspring of the unwanted sex.

Post-birth methods
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 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.

Ethical concerns
The application of these techniques to humans creates moral and ethical concerns. Listed here are some of the more common of those concerns:

Sexual discrimination - The idea that if one sex is preferred over another, those individuals in the non-preferred sex would be at a disadvantage. Opponents of social sex selection argue that the procedure would artificially unequalize the ratio of females to males, leading to discrimination, potential violence and abuse of the smaller group.

Eugenics - Many fear that PGD, in general, is a 'slippery slope' leading to a society where 'non-selected' individuals would be discriminated against. PGD is used primarily in the U.S. for the purpose of reducing birth defects and abnormalities, but opponents fear that there is nothing stopping persons from using PGD for more eugenic-based purposes.

Psychological Implications - There may be psychological implications for both the parents and child if the procedure does not produce a child of the desired sex. Furthermore, problems may also arise if the gender-related expectations of the parents are not subsequently fulfilled by the child. However, it may be the case that any child will fail to fulfill particular parental expectations, so perhaps more emphasis should be placed on promoting acceptance and tolerance within parents as opposed to completely banning sex selection.

Conflict with Kantian principles - Many argue that by selecting the sex of their child, parents are using the child as a means of fulfilling their own desires rather than respecting the child as a person and an end in their own right.

Demographic concerns
In addition to the ethical concerns mentioned, issues of demographics arise in societies where social sex selection is common. A society may exhibit a widespread bias towards having children of a specific gender, either due to cultural biases or economic concerns (e.g. male children may be more employable in the future and thus provide more financial support). When combined with frequent social sex selection, this bias may produce a gender imbalance that has undesirable consequences. This phenomenon has been observed in many nations in the Far East, such as India and China, where social sex selection has produced unnaturally high male/female ratios in the population. China's gender imbalance is further increased by the One Child Policy. In these nations, a lack of opportunity for many men to marry is believed to be producing increases in crime, demand for prostitution, and the selling of brides.

History and folk beliefs
There are a wide variety of social sex selections methods which have not been demonstrated to be effective. Because even implausible and ineffective methods have a "success" rate of 50%, many continued to be recommended by word of mouth.

As early as 330 BC, Aristotle prescribed the ligation (tying off) of the left testicle in men wishing to have boys.

Some people believe that timing conception according to astrological charts can influence a baby's sex, though there is no evidence to support this or any other timing method.

In the mid-1980s, Dr. Glenn Spaulding invented the technique of sorting living sperm, based on DNA content, into motile X (female) and Y (male) subpopulations using flow cytometry. The technique was used to sort both animal and human sperm, and was first described in US Patent 5,439,362. It is offered commercially as an animal husbandry option and for pre-conceptually reducing the probability of sex-linked diseases in people.

Recently, a study published in 2006 indicated that mothers with toxoplasmosis have a significantly higher sex ratio of boys to girls. This has been discussed in connection with the manipulation hypothesis of parasites.

Legality
Social sex selection is illegal in India. 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 and sex-selective abortion continues to be widely practised.