A Ray of Hope for Infertile

New IVF technique

Dr. Hrishikesh Pai offers a ray of hope

By Sudha Hariharan




Dr Pai has been in the field of IVF for the last 14 years. He is a consultant gynaecologist at the Lilavati Hospital Bandra, honorary gynaecologist at the Kurla Bhaba Municipal General Hospital, hon professor at the D Y Patil Medical College, University of Mumbai. He is the administrator of Pearl Family Welfare Hospital, which is one of the leading family planning hospitals in the country. He is the scientific director of three IVF units The Babies and Us Fertility IVF and ICSI Centre at Opera House and the Advanced Fertility Centre at the Lilavati Hospital, Bandra, and at Fortis Hospital, Delhi. He is one of the pioneers in the field of micromanipulation in India. He has also been instrumental in establishing the first assisted laser-hatching unit in India. The unit has delivered one of the first few laser-hatched twins in India in the year 1999. Dr Pai has established the advanced assisted reproductive technology unit at the Batra Hospital, New Delhi.
Dr Pai has been installed as the President of MOGS ( Mumbai Obstretics and Gynaecology Society ) for the year 2008-2009

Of all the topics of special interest to families, none holds a more important place than a baby. A baby in a happy, healthy family means that two people who have joined their lives together in love and respect have created out of their devotion a new human being. A baby then is a sense of our own vision of ourselves carrying on our love, work and life into the future, eventually to be passed on by him to his own children.


Conceiving and bearing a baby presents for most families no problems at all.Medical advances have been such that pregnancy, in itself a normal process , is more comfortable and safer than ever before.There are couples ( 1 out of 10) who have trouble conceiving.
Modern science has found several reasons for this which are equally divided between husband and wife.

Some times it may be a simple, easily corrected anatomical defect in one or the other which prevents the sperm from reaching the egg. Sometimes it is a defect that causes the husband’s sperm either not to develop at all, or to develop in numbers to small or in quality too poor to make fertilization possible.
Whatever the cause, medical science has made it possible for more than half of the apparently infertile couples to achieve pregnancy, provided their problems are properly diagnosed and correctly treated.

A Ray Of HopeIn what should come as a ray of hope to couples unable to conceive naturally, doctors and technicians at Invitro fertilization treatment centers are increasingly using a new technique for freezing embryos, ensuring a better survival rate resulting in successful pregnancies.

Using a technique called vitrification, first successfully conducted in humans in Japan, the embryos are mixed with a freezing media and suddenly plunged into liquid nitrogen. The super high concentration of anti-freeze and rapid drop in temperature never lets the water inside the cell turn into the ice. Due to this sudden drop in temperature the entire embryo is turned into a glassy state, avoiding the ice crystals which are known to damage embryo survival.

This is good news for the patients as the woman does not have to repeatedly undergo removal of eggs. According to doctors, they usually take out 10-15 eggs but put back only two or three. The rest of the developed eggs are stored by freezing, wherein vitrification is showing better results.

Assisted reproductive technology has undergone significant advances and embryo freezing has become a widely used routine procedure that may contribute to increasing cumulative pregnancy rates from every cycle of a successful oocyte recovery and transfer.

Doctors in Mumbai say that their experience over the years has shown that there is an ice crystal formation which damages the eggs in the process of slow freezing. However, in vitrification, there is complete recover of embryos after the freezing process.

The technique demands higher technical skills at the clinics. Several doctors who initiated the technique in Mumbai were trained in Japan. In a recent national conference on gyanaecology in Bhubhaneshwar, vitrification was discussed and the cases debated.

The process of IVF or ICSI

The process of IVF/ ICSI involves production of many eggs which are subsequently fertilized in the incubator. This results in the formation of many embryos. Generally 1- 3 embryos are put back into the womb. The remaining embryos are classified into good and bad embryos based on their appearance under the microscope. The good embryos are frozen and stored in liquid nitrogen containers. The bad embryos are discarded as they cannot withstand the freezing process if the patient does not become pregnant after transfer of the fresh first cycle embryos. These frozen good embryos can be thawed and replaced into the womb with a very good chance of pregnancy.
With transfer of three embryos many patients land up having twins and triplets. The multiple pregnancies have problems of miscarriage or premature babies. Hence many units worldwide are putting back one or two embryos instead of the standard practice of 3 embryos and freezing the rest of the extra good embryos.
Also every time one wants to try for a pregnancy with frozen embryos 3 to 4 embryos are thawed at a time and if these embryos withstand the freezing process they are put into the womb. If this fails to yield a pregnancy they try again with a few more frozen embryos, doing this till they either achieve a pregnancy or all the frozen embryos are finished. In recent times with more efficient ways of freezing, the pregnancy rates per freezing attempt has gone up to 30%. Thus with availability of an
efficient freezing program the cumulative success rate (success rate in the first fresh cycle plus success rate in the subsequent frozen cycles has gone up to 80% for 3 attempts) with availability of good freezing the gynecologist also tends to put lesser embryos back thus reducing the problems of twins and triplets.

There are two types of freezing namely slow freeing and vitrification. The slow freezing is the traditional method of freezing. It is in existence since the 1980s-- in this the temperature of the embryo is slowly lowered from room temperature to minus 40 deg centigrade per minute and then the embryos are stored in liquid nitrogen gas whose temperature is minus196. The problems with slow freezing are many. Firstly, it needs a machine which takes upto nearly two hours to freeze embryos of one patient. Secondly, it is not a very efficient system as many embryos are lost during the thawing process. This in turn hampers the pregnancy rate. It is also not very effective in freezing day 5 mature embryos called Blast cyst.

A new method, more efficient in these aspects is the technique of vitrification .Dr. Pai answers a few questions to shed light on the new technique………




How is conventional slow freezing different from in vitrification?

In conventional slow freezing, the temperature of the embryo goes down at precisely 0.3 degree C per minute. In vitrification, the temperature is dropped at 23,000 degrees C per minute making it 70,000 times faster. At that speed of cooling and at that concentration of antifreeze, ice crystals simply cannot form.


Why are embryos plunged into liquid nitrogen?

In vitrification the embryos are mixed with the freezing media and are suddenly plunged into liquid nitrogen. Due to this sudden drop in temperature the entire embryo is turned into a glassy state without the formation of water crystals (which occurs in slow freezing technique and which are known to damage embryo survival).


What are the advantages of vitrification?

Vitrification has many advantages. It does not need a freezing machine. It is also a very efficient system and the embryo survival of 8 cells day 3, embryos and 150 cells day 5, blast cyst embryo are better than slow freezing. This results in more number of embryos available for embryo transfer following thawing. This is turn increases the cumulative pregnancy rates in IVF as compared to those with slow freezing. It is also very effective in freezing oocytes and day1 embryo called pronuclear embryos or zygotes.

Are there any other benefits of overall freezing?


Other benefits of overall freezing ---either slow freezing or vitrifoication are as follows:

a) many times the lining of the uterus or womb is not ideal for pregnancy in the first fresh cycle; if this is the case one can freeze all the embryos and transfer them in a subsequent natural cycle when the lining is ideal for implantation.
b) Also sometimes a patient may produce a lot of eggs and embryos with resultant swelling of the ovaries. This is called hyper stimulation syndrome and in such situation it is best to avoid transfer and freeze all the embryos. The frozen embryos are then thawed and transferred in the next cycle