At this moment there are more than a million infertile couples in India trying for a conception.IVF (in vitro fertilization) or ‘test tube baby’ is the magic word for infertile couples desperately desirous of a child. Through this technology which is a boon to mankind, many who had no chance of having their own child, are now proud parents. Though by IVF a couple has up to a 60% chance of success, the success rate may vary from couple to couple and may not be the same for all couples.
This article attempts to answer some of the frequently asked questions about IVF clarify certain aspects of IVF- for example, which group of patients need IVF, what happens in an IVF treatment cycle and why all patients do not get pregnant after IVF treatment?
Which group of patients need IVF?
Infertility investigations usually start once the couple has had one year of unprotected regular intercourse. However, it is advisable to investigate and treat earlier if there are known predisposing factors such as age of female partner greater than 35 years, menstrual irregularities, known endometriosis, pelvic infections, undescended testis in the male partner, or when there are pre-existing causes of infertility (eg, previous tubal surgeries). Problems in conception can occur when there is a problem in either the male or female partner. Investigations therefore focus on evaluating the sperm, uterus, egg development and maturation, and fallopian tubes.
Many couples are directly referred for IVF once these investigations are complete. These are patients with either tubal block on both sides or those with severe male factor infertility (< 5 million/ml sperm count). In other cases there are many treatment options available for eg, ovulation induction, intrauterine insemination and surgical treatment of infertility. Many couples conceive after such treatment, but some don’t. After a reasonable duration of trying such treatment these couples should be referred for IVF. The results of IVF are best when the lady is less than 35 years of age. Often much to our frustration, we are unable to help such couples either because of late referral or because the couples have waited too long to start IVF treatment. What happens in an IVF treatment cycle? Typically an IVF cycle consists of ovarian stimulation, egg collection, fertilization, embryo culture and embryo transfer. Ovarian stimulation consists of daily injection of hormones to the female partner with frequent clinical and ultrasonographic monitoring. This usually continues for 10-15 days. Egg retrieval is performed under anaesthesia through the internal route. There are no incisions or scars. The egg and sperm are either mixed (IVF) (Figure 1) or the sperm is injected into the egg (ICSI-intracytoplasmic sperm injection) (Figure 2). The fertilized egg forms the embryo. The embryo is cultured in the laboratory for 2-3 days (Figure 3). Two-three best embryos are selected and transferred into the womb (uterus) on the second or the third day. The pregnancy test is done 14 days after the day of embryo transfer. What is the success rate of this process? It all sounds so logical and definitive that one would expect success in every case! But unfortunately this is not the reality. One must understand that in the entire process of IVF each step is a hurdle that has to be negotiated successfully. For example, not all women respond to ovarian stimulation, not all eggs are mature, not all eggs fertilize to make good embryos and not all embryos implant. Therefore, there is an attrition or drop out at each stage. It is at the stage of implantation that there is a huge scope for further research. Implantation is the process where the uterus accepts the embryo which then develops to form the baby. Much work has been done on this aspect of IVF and medications such as steroids, aspirin, heparin, sildenafil are being tried to improve implantation rates. The overall success rate of IVF is about 35% per treatment cycle. In order words 4 out 10 , who otherwise had given up all hopes of parenting a child would conceive after attempting IVF. World over the success rate is highest in younger women where it can reach up to 60% per treatment cycle. In case of failure, IVF may be tried again and the cumulative pregnancy rate over 3 cycles may go as high as 70%. In order to give the optimum benefit to the patient it is essential that the infertile couple is offered the right treatment at the right time. It is also essential that patients understand the entire process of IVF. We are in an era of transparency and constant dialogue with patients. They should be involved in decision making. They must understand the strong points and drawbacks of the entire IVF process. Once there is complete understanding of the process a lot of stress associated with such intensive treatment will automatically be allayed.
The age of woman has a major impact on IVF success rates, if age of woman is less than 35 years, the success rate is higher. The possibility of success falls dramatically after 40 years. Other factors that determine success rate are:
Eggs and sperm quality
Condition of endometrium
Ease of embryo transfer
The major complication is risk of multiple births, this may lead to:
Potential for long term damage
The other major complication is ovarian hyperstimulation syndrome. In this condition fluid accumulates inside the abdomen and lungs. Usually it settles on its own with proper fluid management. In rare cases hospital admission and intensive care is required.