Contents
The study of human anatomy and physiology is one of the crucial Biology Topics for medical professionals and researchers.
Types of Assisted Reproductive Techniques (ART) | How the Sperm Donor Process Works
These are the application of reproductive technology to solve infertility problems. Some important techniques are IVF, ZIFT, and GIFT.
IVF (In-Vitro Fertilization)
In-vitro fertilization is the technique of fertilization carried out in a glass container outside the body of the mother followed by embryo transfer or ET. This procedure is followed in a test tube baby. The technique was developed by Patrick Steptoe and Dr. Robert Edwards of the UK in 1978. This technique was carried out in India by Indra Hinduja (1986) in Mumbai and Baidyanath Chakraborty (1968) in Kolkata.
Procedure of IVF
1. Collection of Gametes:
The female is given FSH soon after menstruation so that ovulation takes place. A mature ovum is collected from the female body with the help of laparoscopy. At the same time, spermatozoa are also collected from the male body.
2. Union of Female and Male Gametes:
Both male and female gametes are placed in a culture media where both the gamete unite together (i.e., fertilization) and form a zygote.
3. Production of Early Embryo:
The fertilized egg is put in another medium for cleavage. After repeated cell divisions zygote becomes a 16-cell stage embryo, which is called a blastocyst.
4. Implantation of Blastocyst:
The blastocyst is introduced through the cervix into the uterus for implantation in the endometrium for further growth.
Significance of IVF
- IVF can fulfill the wishes of infertile couples.
- FVF allows single-sex couples and post-menopausal women to have children.
- With further development, it is also possible to apply this technique in the production of specific organs and tissues for transplantation.
- IVF can be an expensive procedure. But it is quite demanding emotionally, psychologically. There is a relatively high failure rate combined with a desperate desire for success.
GIFT (Gamete Intrafallopian Transfer)
It was developed by Asch et. al in 1984. In this procedure, two unfertilized oocytes and 2-4 lakh motile sperms are passed through the fallopian tube through the laparoscope. Fertilization occurs in-vivo.
Procedure of GIFT
The two collected oocytes and about 2-4 lakh motile sperms for each fallopian tube are placed in a plastic container. By the use of a laparoscope, it is then transferred and inserted 4 cm into the distal end of the fallopian tube where the oocytes and sperms combination is injected. It is a more expensive process than In Vitro Fertilization or IVF.
ZIFT (Zygote Intrafallopian Transfer)
This technique was developed by Devroey et. al in 1986. One-day-old in-vitro fertilized zygote (upto 8 blastomeres) is introduced into the fallopian tube through either laparoscope per abdomen or uterine ostium under ultrasonic guidance.
Other than those above-mentioned methods there are also a few methods such as
Artificial Insemination (AI)
When the semen collected either from the husband or a healthy donor is introduced with a syringe into the region of the neck of the womb means either into the vagina or uterus, in the hope that the sperm will then fertilize the egg. This process is known as artificial insemination. To skip the initial barrier that is made up of mucus of the cervix doctor can recommend artificial insemination because many sperms are unable to cross the mucus barrier.
Artificial insemination is used in the following situations:
- Low sperm count in male partners.
- Increased acidity in the vaginal wall kills the spermatozoa in an abnormal manner.
- When the vaginal cell kills the spermatozoa abnormally.
- When the husband is affected by a sickness that makes him incompatible to ejaculate sperm.
Intra Uterine Insemination (IUI)
It is a treatment procedure for infertile couples that involves placing sperm inside the woman’s uterus to facilitate fertilization. It provides a fair chance to get the ovum fertilized by sperm.
Surrogate Mother
When a woman has problems in having or carrying a child means, the woman is infertile then the need for a surrogate mother is seen. In this technique, sperm collected from the husband of an infertile woman can be introduced into the womb of a surrogate mother. Now surrogate mother becomes pregnant. The surrogate mother carries the baby in her womb until it’s born.
Embryo Donation
Few women are incapable of producing eggs. In such cases, an egg can be taken from a donor and fertilized with the sperm of the husband in vitro. After fertilization, the fertilized embryo is then transferred into the infertile mother’s womb. She now continues the pregnancy and gives birth to the child.
IUT (Intra Uterine Transfer)
The embryo is transferred in the uterus at 8 cell blastomere stage, for further development and implantation. This method is undertaken to overcome the abnormalities defect or obstructions in the fallopian tube.
ICSI (Intra Cytoplasmic Sperm Injection)
It is a specialized form of IVF to treat male infertility. In this treatment, a single potent sperm is choosen by a doctor and then injected directly into the cytoplasm of the ovum.
Test Tube Baby
A test tube baby is the term that refers to a child that is conceived outside the woman’s body. The process is referred to as “in vitro” (outside the body) fertilization. Simply put, eggs are removed from the mother’s ovary and incubated with sperm from the father.
Brief History
There was a transient biochemical pregnancy reported by Australian Foxton School researchers in 1953. John Rock was the first to extract an intact fertilized egg. After much research, in 1977, Dr Patrick Steptoe and Dr. Rober Edward successfully carried out a pioneering conception that resulted in the birth of the world’s first baby to be conceived by IVF, Louise Brown on 25th July 1978 in the UK. In October 1978, it was reported that Dr. Subhas Mukhopadyay, a relatively unknown physician from Kolkata, India was performing experiments and this resulted in a test tube baby, later named Durga (alias Kanupriya Agarwal).
Test Tube Baby Method
Theoretically, in vitro fertilization could be performed by collecting the contents from a woman’s fallopian tubes or uterus after natural ovulation, mixing it with sperm, and reinserting the fertilized ova into the uterus. However, without additional techniques, the chances of pregnancy would be extremely small. The additional techniques that are routinely used in IVF include ovarian hyperstimulation to generate multiple eggs or ultrasound-guided transvaginal oocyte retrieval directly from the ovaries; after which the ova and sperm are prepared, as well as culture and selection of resultant embryos before embryo transfer into a uterus.
1. Ovarian Hyperstimulation:
Ovarian hyperstimulation is the stimulation to induce the development of multiple follicles of the ovaries. It should start with response prediction by e.g., age, antral follicle count, and level of anti-Mullerian hormone. The resulting prediction of e.g., poor or hyper-response to ovarian hyperstimulation determines the protocol and dosage for ovarian hyperstimulation. For ovarian hyperstimulation in itself, injectable gonadotropins (usually FSH analogues) are generally used under close monitoring. Such monitoring frequently checks the estradiol level and, by means of gynecologic ultrasonography, follicular growth. Typically approximately 10 days of injections will be necessary.
2. Natural Cycle Invitro Fertilization:
There are several methods termed natural cycle IVF
- IVF uses no drugs for ovarian hyperstimulation, while drugs for ovulation suppression may still be used.
- IVF uses ovarian hyperstimulation, including gonadotropins, but with a GnRH antagonist protocol so that the cycle initiates from natural mechanisms.
- Frozen embryo transfer; IVF using ovarian hyper-stimulation, followed by embryo cryopreservation, followed by embryo transfer in a later, natural cycle.
IVF using no drugs for ovarian hyperstimulation was the method for the conception of Louise Brown. This method can be successfully used when women want to avoid taking ovarian-stimulating drugs with their associated side effects. HFEA has estimated the live birth rate to be approximately 1.3% per IVF cycle using no hyperstimulation drugs for women aged between 40-42.
3. Final Maturation Induction:
When the ovarian follicles have reached a certain degree of development, induction of final oocyte maturation is performed, generally by an injection of human chorionic gonadotropin (hCG). Commonly, this is known as the “trigger shot”. hCG acts as an analogue of luteinizing hormone, and ovulation would occur between 38 and 40 hours after a single hCG injection, but the egg retrieval is performed at a time usually between 34 and 36 hours after hCG injection, that is, just prior to when the follicles would rupture. This avails for scheduling the egg retrieval procedure at a time when the eggs are fully mature. hCG injection confers a risk of ovarian hyperstimulation syndrome.
4. Egg Retrieval:
The eggs are retrieved from the patient using a transvaginal technique called transvaginal oocyte retrieval, involving an ultrasound-guided needle piercing the vaginal wall to reach the ovaries. Through this needle follicles can be aspirated, and the follicular fluid is passed to an embryologist to identify ova. It is common to remove between ten and thirty eggs. The retrieval procedure usually takes between 20 and 40 minutes, depending on the number of mature follicles, and is usually done under conscious sedation or general anesthesia.
5. Egg and Sperm Preparation:
In the laboratory, the identified eggs are stripped of surrounding cells and prepared for fertilization. An oocyte selection may be performed prior to fertilization to select eggs with optimal chances of a successful pregnancy. In the meantime, semen is prepared for fertilization by removing inactive cells and seminal fluid in a process called sperm washing. If semen is being provided by a sperm donor, it will usually have been prepared for treatment before being frozen and quarantined, and it will be thawed ready for use.
Co-incubation: The sperm and egg are incubated together at a ratio of about 75000 : 1 in a culture media in order for the actual fertilization to take place.
6. Embryo Culture:
The main durations of embryo culture are until the cleavage stage (day two to four after co-incubation) or the blastocyst stage (day five or six after co-incubation). Embryo culture until the blastocyst stage confers a significant increase in live birth rate per embryo transfer but also confers a decreased number of embryos available for transfer and embryo cryopreservation, so the cumulative clinical pregnancy rates are increased with cleavage stage transfer.
7. Embryo Selection:
Laboratories have developed grading methods to judge oocyte and embryo quality. In order to optimize pregnancy rates, there is significant evidence that a morphological scoring system is the best strategy for the selection of embryos. Since 2009 when the first time-lapse microscopy system for IVF was approved for clinical use, morphogenetic scoring systems have been shown to improve to pregnancy rates further.
8. Embryo Transfer:
Embryos are failed by the embryologist based on the number of cells, evenness of growth, and degree of fragmentation. The number to be transferred depends on the number available, the age of the woman, and other health and diagnostic factors. The embryos judged to be the “best” are transferred to the patient’s uterus through a thin, plastic catheter, which goes through her vagina and cervix. Several embryos may be passed into the uterus to improve the chances of implantation and pregnancy.
Sperm Bank
A sperm bank, semen bank, or cryobank is a facility or enterprise that collects and stores human sperm from sperm donors for use by women who need donor-provided sperm to achieve pregnancy. Sperm donated by the sperm donor is known as donor sperm, and the process of introducing the sperm into the woman is called artificial insemination, which is a form of third-party reproduction. From a medical perspective, a pregnancy achieved using donor sperm is no different from a pregnancy achieved using partner sperm, and it is also no different from a pregnancy achieved by sexual intercourse.
Sperm Bank Procedure
1. Screening of Donors:
A sperm donor must generally meet specific requirements regarding age and medical history. Sperm banks typically screen potential donors for a range of diseases and disorders, including genetic diseases, chromosomal abnormalities, and sexually transmitted infections that may be transmitted through sperm. The screening procedure generally also includes a quarantine period, in which the samples are frozen and stored for at least 6 months after which the donor will be re-tested. This is to ensure no new infections have been acquired or have developed during the period of donation. Providing the result is negative, the sperm samples can be released from quarantine and used in treatments. Children conceived through sperm donation have a birth defect rate of almost a fifth compared with the general population.
2. Collection:
A sperm donor will usually donate sperm to a sperm bank under a contract, which would typically specify the period during which the donor will be required to produce sperm, which generally ranges from 6-24 months depending on the number of pregnancies which the sperm bank intends to produce from the donor.
3. Processing of Sperm:
Sperm banks and clinics usually ‘wash’ the sperm sample to extract sperm from the rest of the material in the semen. A cryoprotectant semen extender is added if the sperm is to be placed in frozen storage. One sample can produce 1-20 vials or straws, depending on the quantity of the ejaculate and whether the sample is ‘washed’ or ‘unwashed’. ‘Unwashed’ samples are used for intracervical insemination (ICI) treatments, and ‘washed’ samples are used in intrauterine insemination (IUI) and for in-vitro fertilization (IVF) procedures.
4. Storage:
The sperm is stored in small vials or straws holding between 0.4 and 1.0 ml of sperm and cryogenically preserved in liquid nitrogen tanks. Before freezing, sperm may be prepared (washed or left unwashed) so that it can be used for intracervical insemination (ICI), intrauterine insemination (IUI) or for in-vitro fertilization (IVF) or assisted reproduction technologies (ART). Following the necessary quarantine period, which is usually 6 months, a sample will be thawed and used to artificially inseminate a woman or used for another assisted reproduction technologies (ART) treatment.
Ova Bank
An Ova bank or cryobank or egg cell bank is a facility that collects and stores luman ova, mainly from ova donors, primarily for the purpose of achieving pregnancies of either the donor, at a later time (z.e., to overcome issues of infertility), or through third party reproduction, notably by artificial insemination. Ova donated in this way is known as donor ova.
General Awareness
Reproductive health occupies a central position in the identity of health as well as the development of a given population. However, the events of reproductive health are usually found in women who due to their biological function invariably bear the greater burden of the shortcomings of reproductive health such as unsafe motherhood or unsafe abortion.
Family planning helps everyone (women, children, men, families, nations, and the earth). Specifically, it protects women from unwanted pregnancies, thereby saving them from high-risk pregnancies or unsafe abortions. If all women could avoid high-risk pregnancies, the number of maternal deaths could fall by one-quarter. Also, other benefits accruing from family planning methods include the prevention of cancers, sexually transmitted infections, and HIV/AIDS.
The WHO assessed in 2008 that “Reproductive and sexual ill-health accounts for 20% of the global burden of ill-health for women, and 14% for men”. Reproductive health is a part of sexual and reproductive health and rights.
Human Resources for Reproductive Health
The operationalization of the new concept of reproductive health will mean changes in skills, knowledge, attitudes, and management. People will have to work together in new ways. Healthcare providers will have to collaborate with others, including NGOs, women’s health advocates, and young people. Managerial and administrative changes will also be needed because integrated services can impose, at least initially, greater burdens on already over-stretched staff and require attention to planning and logistics in order to ensure the availability and continuity of services.
Training for reproductive health workers will need to focus on improving both technical and interpersonal skills. Additional training, particularly in counseling skills and in ways of reaching out to under-served groups will be essential elements of such training. The backup and support of functioning referral systems will be essential elements if the full range of reproductive health concerns is to be adequately addressed.