Wednesday, 31 July 2013

IVF - the hope comes true for infertile couples

Sperm Collection and Preparation
On the day of egg collection, the husband gives a sperm sample. The semen specimen should be obtained following a 3-4 day abstinence from sexual activity and masturbation is the preferred method of collection. A shorter or longer period of time or the use of a different method of collection may affect semen parameters. After collection the semen sample is delivered to the lab where it is properly prepared for IVF. The purpose of the preparation is to isolate the motile spermatozoa from other elements of the semen and activate them in order to be capable to fertilize the mature oocytes.

It should be noticed that masturbation, especially at the clinic, is sometimes difficult and stressful for men on the day of egg collection. Therefore men could bring the semen sample from home or can freeze a sample several days before the day of oocyte retrieval (fresh samples are always preferred). In cases of men with azoospermia, spermatozoa are retrieved directly from the testis (surgical sperm retrieval).

Egg Retrieval
The ability to collect mature eggs from a woman's ovaries for fertilization outside of the body has revolutionized fertility treatment. Originally developed as a way to help women whose fallopian tubes were irreparably blocked, IVF now allows couples who suffer from a wide range of fertility problems to successfully conceive. In vitro fertilization begins with ovulation induction, a process of stimulating and monitoring the ovaries. Once it is determined that the ovarian follicles are the right size and the eggs ready to be collected, a dose of human chorionic gonadotropin (hCG) is administered to trigger the final maturation process and egg retrieval will take place approximately 36 hours later. Prior to the procedure, anesthesia will be given. In most cases, egg retrieval is performed under moderate sedation (aka MAC), allowing the patient to be asleep for the procedure. The actual technique used to collect eggs for in vitro fertilization is known as an ultrasound-guided transvaginal aspiration.

While an ultrasound probe is used to provide a visual image of the ovary and the surrounding structures, a very fine needle is inserted through the upper wall of the vagina and into the ovary. Through magnification of the ultrasound image, the physician can locate the individual follicles that contain mature eggs and apply gentle suction to remove the contents of each one, which is known as aspiration. The fluid and egg from each follicle are collected into an individual container, which will then be taken to the lab for examination and preparation for fertilization. The procedure is performed on both ovaries, usually taking between 10 and 15 minutes to complete. Once the egg retrieval process is finished, the patient will remain under observation for one or two hours before being sent home. Patients may experience some discomfort after egg retrieval and are encouraged to rest as much as possible. Mild soreness, cramping, and light spotting are normal.

Vigorous exercise and other strenuous activities should be avoided. Specific instructions will be provided prior to the procedure and should be followed carefully. Progesterone, a hormone that would normally be released by the follicle after ovulation, is vital to the support of early pregnancy. Because aspiration of the follicles can interrupt the normal hormonal process and prevent adequate amounts of progesterone from being produced, the patient will generally be given supplemental progesterone from the time of egg retrieval through the end of the cycle.

The whole process is performed under mild sedation with a recovery period of approximately an hour. However, it is important to notice that for safety reasons, women scheduled for egg retrieval must be at the clinic at least 30 minutes before the procedure in order to have a cardiograph and talk to the anesthesiologist about allergies, any medication they are taking and any other health problems they may have. Last but not least, women programmed for this procedure shouldn’t eat or drink anything from the previous night.

Oocyte Fertilization
Several hours after egg retrieval and semen preparation, fertilization occurs. More specifically at a conventional IVF cycle the mature oocytes are placed in 4-well dishes of culture medium containing processed sperm. One of the spermatozoa will penetrate and fertilize the oocyte. In cases of severe male infertility, other laboratory techniques are required following egg retrieval. Fertilization may be assisted by intracytoplasmic sperm injection (ICSI), a micromanipulation technique which involves the injection of a sperm directly into the egg. The eggs are then incubated in the lab overnight.

The next morning, 16-18 hours after the time of fertilization, fertilization check is performed by the embryologists. The first signs of normal fertilization are shown by the presence of two pronuclei (small round structures) within the egg. The fertilization rate is usually between 50 and 100%. The maturity of the oocytes, semen parameters, handling procedures and culture systems are some factors that are responsible for the variance in the fertilization rate.

Embryo culture, selection and transfer
The earliest stages of human development, until day five or six after fertilization, normally occur in the woman’s fallopian tube. However, after in vitro fertilization (IVF), much of this period of early development occurs in the laboratory. The conditions under which the embryos are “cultured” have been carefully formulated to provide an environment that as closely as possible that of the fallopian tube. Recently, commercially prepared culture media have become available. These media support embryo development in the laboratory for up to six days. By allowing the embryo to reach the blastocyst stage, we can make a more stringent selection of those to be transferred during an IVF cycle; as a result, these systems may be preferable for patients who would prefer or benefit from a one- or two-embryo transfer.

Once the embryos have been created in the laboratory, they are placed into the uterus. At this point, in order for pregnancy to occur, an embryo must implant into the uterine lining. For many patients, the two-week wait between the embryo transfer procedure and the initial pregnancy test is the most difficult stage of the process. While the embryos are developing in the laboratory, they are monitored for rate of growth, size, form, and signs of irregularity. Based on this data, the embryos are graded by quality, which helps us to estimate which are most likely to successfully implant and continue to develop. Typically, the embryos of the highest grade are selected for the first IVF transfer. Embryos with significant abnormalities are not suitable for transfer and will be discarded. In most instances, no more than two or three embryos will be transferred during any given IVF cycle. This number allows the best chances for implantation while still keeping the risk of a multiple pregnancy to a minimum. In some cases, depending on age and other factors, our physicians recommend electing a single embryo transfer. Any additional embryos that are created will be cryopreserved for later transfer. The embryo transfer procedure will be scheduled for three to five days after the egg retrieval. In IVF cycles where frozen embryos are to be used, the patient will be closely monitored via ultrasound and the embryos will be placed about two days after ovulation takes place.

This stage of in vitro fertilization treatment involves threading a thin catheter through the opening in the cervix, through which the embryos are gently deposited into the uterus. There is very little discomfort during this part of treatment and anesthesia is not necessary. After the transfer procedure, our IVF patients are advised to take it easy for the next few days. Physical activity should be limited and strenuous exercise should be avoided. Although there is little that can be done at this point that will affect the chances of successful implantation, eating well, getting enough sleep, and minimizing stress will go a long way toward the health and wellbeing of the patient. The process of implantation is complex and unpredictable. First, the embryo must escape, or hatch, from the zona Pellucida. Even if the embryos are transferred on day three, this will not occur until after the embryos have reached the blastocyst stage on day five or six. Once an embryo has hatched, it must attach to the endometrium, or uterine lining, and gradually become imbedded in it. Once an embryo has completed this process, pregnancy is achieved and the in vitro fertilization cycle is a success.

Approximately fourteen days after the embryo transfer procedure, a blood test will be conducted to measure the amount of human chorionic gonadotropin (HCG) in the patient's system. This hormone is released only after implantation and is an accurate indicator of pregnancy. However, because HCG is sometimes used during the ovulation induction process to trigger the final maturation of the oocytes, small amounts may exist even if the patient is not pregnant. For this reason, at-home pregnancy tests that detect the presence of HCG but do not measure the quantity are not considered accurate for women undergoing in vitro fertilization. Elevated levels of HCG indicate that implantation has occurred and the patient is pregnant. If pregnancy is detected, the patient will then undergo an ultrasound examination to confirm the findings, determine how many embryos have implanted, and ensure that everything is progressing normally.

If pregnancy has occurred, progesterone treatments will be continued for a period of time and then be gradually reduced as the patient's body takes over normal hormone production. The patient will continue to visit our IVF Centre for blood work and ultrasounds during the early weeks of pregnancy to ensure that everything is proceeding as it should. Once we are able to detect the fetal heartbeat, the patient will be referred to an OB-GYN (if she does not have one already), who will handle the remainder of the patient's prenatal care. A high-risk obstetrician is only necessary if certain medical problems are a factor.

If pregnancy has not occurred, progesterone supplements will be ceased and the cycle will come to an end. If the couple has opted to try another in vitro fertilization cycle, we may recommend waiting one or even two complete menstrual cycles before resuming treatment. This allows the body to rest and gives us a chance to examine our treatment strategy and possibly change our approach in future cycles. In subsequent IVF cycles, the ovulation induction phase may not be necessary if frozen embryos are available for transfer.

Complications & Risk Factors after Embryo Transfer
Assisted reproduction technique (ART) is an efficacious treatment in sub fertile couples. So far little attention has been paid to the safety of ART, i.e. to its adverse events and complications; the consensus meeting on Risks and Complications in ART.

Multiple pregnancies
If 25% of all pregnancies after IVF/ICSI are twin pregnancies, 40% of all babies born after ART are born as part of a twin pair. Many physicians and patient couples underestimate the negative consequences of twin pregnancies. Perinatal as well as maternal mortality and morbidity are increased in multiple pregnancies as compared with singleton Pregnancies due to a higher rate of prematurity and low birth weights in the children; and due to pregnancy complications in the mothers. Furthermore, parents of multiple births have more stress, and siblings of multiples are more likely to have behavior problems.

Long-term effects of ART on women
Hormonal and reproductive factors are involved in the etiology of breast cancer and cancers of the female genital tract. Therefore, the effect of fertility drugs on the risk of these
Cancers has been investigated. Many studies have not been able to reach solid conclusions due to low statistical power, lack of control for important confounders (such as cause of sub fertility and parity) and short duration of follow-up.

Effects of ART on offspring
Much concern has been expressed about the health of children born after ART. In particular, the risk of boys born to couples with male factor sub fertility has drawn attention, since in a substantial number of male factor sub fertility cases, a genetic cause can be suspected.

Patient selection and counseling for eSET (elective single-embryo transfer)
It was agreed that the essential aim of IVF/ICSI is the birth of one single healthy child, with a twin pregnancy being regarded as a complication. The chances of having a single healthy child after eSET have increased, and equal the spontaneous pregnancy rate in a normally fertile couple.

Women who can get pregnant without fertility drugs or medical procedures usually have only one baby. Women who need fertility treatment are at higher risk to get pregnant with twins, and rarely with triplets or more. This is called multiple gestations. Multiple gestations can increase the risk of pregnancy for the mother and for all the babies. Multiple gestations are risky for the babies. Because there are too many babies in the womb, you may have a miscarriage. A miscarriage occurs when your pregnancy ends without the birth of any infants that can survive, before the 20th week of pregnancy. Or you could have a premature delivery when the babies may be born too early (but after 20 weeks of pregnancy) and have problems with lungs, stomach, or intestinal tract. They may have bleeding in the brain, which can cause problems with the baby's brain, nervous system, and hamper its development. If the babies are born very early, they will probably be very small and may even die.  Twins, triplets, and other multiples are more likely to have problems with their brain development and nerves if they are born early. One of the more common problems is cerebral palsy, a condition that affects movement. Other problems associated with multiple births may not present for many years after delivery

Embryo transfer and elective single embryo transfer have become popular topics as more couples turn to fertility treatments to conceive. Our Fertility doctor takes your age and in vitro fertilization (IVF) prognosis into account when performing embryo transfer. Pahlajani Test Tube Baby has a clear guidelines offer you the best chances for a healthy pregnancy and delivery. Do you have a good prognosis for IVF? A good, or favorable, IVF prognosis applies to women who:
» Are in their first IVF cycle
» Have healthy embryos or multiple frozen embryos
» Have already had success with IVF

If you are under 35, and have a favorable prognosis for IVF, you are more likely to conceive with a single embryo transfer. If you're over 35 and have a good IVF prognosis, our doctor may prefer to transfer more than one embryo.
» Under 35: 1-2 embryos
» 35 to 37: 2 embryos
» 38 to 40: 2 to 3 embryos
» 41 to 42: 3 to 5 embryos

Becoming pregnant with multiples increases the risk of complications for you and your babies. Single embryo transfer can help you avoid these risks. The most common complications associated with multiples are increased rates of preterm labor and preterm delivery. Preterm delivery can cause a host of problems for the infant, including:
» Respiratory, growth, and digestive problems
» Long-term learning and developmental difficulties
» Low birth weight

Complications for mom are also increased with multiple gestations. Here are some of the increased health risks for moms of multiples:
» C-section
» Emotional stress
» Gestational diabetes
» High blood pressure and preeclampsia
» Increased cost for medical care
» Increased risk of miscarriage

This is why doctors prefer single embryo transfer, or transferring a lower number of embryos during IVF, when possible.

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