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Assisted reproductive technology
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Assisted reproductive technology (ART) is a general term referring to methods used to achieve pregnancy by artificial or partially artificial means. It is reproductive technology used in infertility treatment, which is the only application routinely used today of reproductive technology. However, there is yet no strict definition of the term.
e there is no consensus on the definition, generally the process of intercourse is bypassed either by insemination (example IUI) or fertilization of the oocytes in the laboratory environment (i.e.
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Encyclopedia
Assisted reproductive technology (ART) is a general term referring to methods used to achieve pregnancy by artificial or partially artificial means. It is reproductive technology used in infertility treatment, which is the only application routinely used today of reproductive technology. However, there is yet no strict definition of the term.
Definitions
While there is no consensus on the definition, generally the process of intercourse is bypassed either by insemination (example IUI) or fertilization of the oocytes in the laboratory environment (i.e. in IVF).
- The Centers for Disease Control and Prevention(CDC) -- which is required as a result of the 1992 Fertility Clinic Success Rate and Certification Act to publish the annual ART success rates at U.S. fertility clinics -- defines ART to include "all fertility treatments in which both eggs and sperm are handled. In general, ART procedures involve surgically removing eggs from a woman’s ovaries, combining them with sperm in the laboratory, and returning them to the woman’s body or donating them to another woman." According to CDC, "they do not include treatments in which only sperm are handled (i.e., intrauterine—or artificial—insemination) or procedures in which a woman takes medicine only to stimulate egg production without the intention of having eggs retrieved."
Procedures
Medication
Most fertility medication are agents that stimulate the development of follicles in the ovary. Examples are gonadotropins and gonadotropin releasing hormone.
Manual
To this category counts all forms of ART techniques that uses more substantial and forceful interventions than giving medication. In vitro fertilisation (IVF) and expansions of it (e.g. OCR, AZH, ICSI, ZIFT) are the most prevalent. However, there are also other manual ART, not necessarily dependent on IVF (e.g. PGD, GIFT, SSR).
In vitro fertilisation
In vitro fertilisation (IVF) is the technique of letting fertilisation of the male and female gametes (sperm and egg) occur outside the female body.
Expansions of IVF
The following are techniques involved in, or requiring, in vitro fertilisation. In vitro fertilization does not necessarily involve each technique.
- Transvaginal ovum retrieval (OCR) is the process whereby a small needle is inserted through the back of the vagina and guided via ultrasound into the ovarian follicles to collect the fluid that contains the eggs.
- Assisted zona hatching (AZH) is performed shortly before the embryo is transferred to the uterus. A small opening is made in the outer layer surrounding the egg in order to help the embryo hatch out and aid in the implantation process of the growing embryo.
- Intracytoplasmic sperm injection (ICSI) is beneficial in the case of male factor infertility where sperm counts are very low or failed fertilization occurred with previous IVF attempt(s). The ICSI procedure involves a single sperm carefully injected into the center of an egg using a microneedle.
- Autologous endometrial coculture is a possible treatment for patients who have failed previous IVF attempts or who have poor embryo quality. The patient’s fertilized eggs are placed on top of a layer of cells from the patient’s own uterine lining, creating a more natural environment for embryo development.
- In zygote intrafallopian transfer (ZIFT), egg cells are removed from the woman's ovaries and fertilized in the laboratory; the resulting zygote is then placed into the fallopian tube.
- Egg donors are resources for women with no eggs due to surgery, chemotherapy, or genetic causes; or with poor egg quality, previously unsuccessful IVF cycles or advanced maternal age. In the egg donor process, eggs are retrieved from a donor’s ovaries, fertilized in the laboratory with the sperm from the recipient’s partner, and the resulting healthy embryos are returned to the recipient’s uterus.
- A gestational carrier is an option when a patient’s medical condition prevents a safe pregnancy, when a patient has ovaries but no uterus due to congenital absence or previous surgical removal, and where a patient has no ovaries and is also unable to carry a pregnancy to full term.
- By cryopreservation, eggs, sperm and reproductive tissue can be preserved for later IVF.
Others
The following Assisted Reproduction techniques don't necessarily involve IVF.
- In gamete intrafallopian transfer (GIFT) a mixture of sperm and eggs is placed directly into a woman’s fallopian tubes using laparoscopy following a transvaginal ovum retrieval.
- Preimplantation genetic diagnosis (PGD) involves the use of Fluorescent In Situ Hybridization (FISH) or Polymerase Chain Reaction (PCR) DNA amplification to help identify genetically abnormal embryos and improve healthy outcomes.
- 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. Pre-implantation techniques include PGD, but also sperm sorting.
- Artificial insemination (AI) is when sperm is placed into a female's uterus (intrauterine) or cervix (intracervical) using artificial means rather than by natural copulation.
- Conception devices, such as a conception cap are used to aid conception by enhancing the natural process. Conception caps are used by placing semen into a small conception cap, then placing the cap onto the cervix. This holds the semen at the cervical os, protecting the semen from the acidic vaginal secretions and keeping it in contact with the cervical mucus.
- Artificial insemination by donor is used in situations where the woman doesn't have a partner with functional sperm. Instead, a sperm donor supplies the sperm.
- In surgical sperm retrieval (SSR) the reproductive urologist obtains sperm from the vas deferens, epididymis or directly from the testis in a short outpatient procedure.
- Tuboplasty is a surgery to restore patency of obstructed fallopian tubes.
- A fertilized embryo can be cryopreserved. The latter insertion in the body is by the technique Frozen Embryo Transfer (FET).
Risks
The majority of IVF-conceived infants do not have birth defects.
However, some studies have suggested that assisted reproductive technology is associated with an increased risk of birth defects.
In the largest U.S. study, which used data from a statewide registry of birth defects,
6.2% of IVF-conceived children had major defects, as compared with 4.4% of naturally conceived children matched for maternal age and other factors (odds ratio, 1.3; 95% confidence interval, 1.00 to 1.67).
The main risks are:
Other risk factors are:
Sperm donation is an exception, with a birth defect rate of almost a fifth compared to the general population. It may be explained by that sperm banks accept only people with high sperm count.
Costs
United States of America
Not everyone in the U.S. has insurance coverage for fertility investigations and treatments. Many states are starting to mandate coverage, and the rate of utilization is 277% higher in states with complete coverage.
There are some health insurance companies that cover diagnosis of infertility but frequently once diagnosed will not cover any treatment costs.
2005 approximate treatment/diagnosis costs (United States, costs in US$):
- Initial workup: hysteroscopy, hysterosalpingogram, blood tests ~$2,000
- Intrauterine Insemination (IUI) fka Artificial insemination ~ $200- 900 per. trial
- Sonohysterogram (SHG) ~ $600 - 1,000
- Clomiphene citrate cycle ~ $ 200 - 500
- IVF cycle ~ $10,000 -30,000
- Use of a surrogate mother to carry the child - dependent on arrangements
Another way to look at costs is to determine the cost of establishing a pregnancy. Thus if a clomiphene treatment has a chance to establish a pregnancy in 8% of cycles and costs $500, it will cost ~ $6,000 to establish a pregnancy, compared to an IVF cycle (cycle fecundity 40%) with a corresponding cost of ($12,000/40%) $90,000
For the community as a whole, the cost of IVF on average pays back by 700% by tax from future employment by the conceived human being.
United Kingdom
In the UK all patients have the right to preliminary testing, provided free of charge by the National Health Service. However, treatment is not widely available on the NHS and there can be long waiting lists. Many patients therefore pay for immediate treatment within the NHS or seek help from private clinics.
Sweden
In Sweden, official fertility clinics provide most necessary treatments and initial workup, but there are long waiting lists, especially for egg donations, since the donor gets just as low reward as the receiving couple are charged. However, there are private fertility clinics.
See also
External links
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