A significant breakthrough, the Laser Assisted Hatching (LAH) has nearly doubled the success rates of assisted reproduction techniques such as IVF and micromanipulation. The LAH is a seemingly simple method of making sure that the embryo -- fertilised in a laboratory through the IVF or MM techniques -- implants itself when transferred to the uterus. Non-implantation means a failed attempt at pregnancy irrespective of the assisted reproduction technique chosen.

The LAH uses a diode laser ray of eight to 12 milliseconds to breach the outer protective layer of the embryo called the zona. The ``hatched'' embryo is immediatelytransferred to the uterus greatly enhancing the chances of implantation, and therefore pregnancy. First time in South-East Asia, the LAH method has delivered a success rate of nearly 60 per cent in the first batch of 24 women under treatment at the Jaslok Hospital and Research Centre. Success rate of IVF when it started in 1978 was barely five per cent; the accepted norm now is about 30 per cent.

``With the LAH, we have managed to refine the assisted pregnancy procedure. There are chemical and mechanical hatching methods as well but the LAH is superior in that it is faster, safer and more precise,'' said Dr Firuza R. Parikh, director, department of infertility management and assisted reproduction at Jaslok. With a four-member team of doctors and technicians, Dr Parikh began her first LAH procedure in December last year. Their paper on the subject has been approved for publication in the Indian Journal of Obstetrics and Gynaecology.

The LAH is particularly useful for women older than 35 years or those whohave been through IVF or MM procedures once or twice earlier. In such cases, the zona is usually very thick -- above 18 microns as against the normal of below 15 microns -- which prevents the embryo from hatching the protective layer. ``Our observations and studies showed that the embryo quality was excellent but the protective zona became a trap,'' explained Dr Parikh. The irradiation is not known to affect the embryo in any way.

While the chemical method used acid tyrode to breach the zona, the mechanical method involved using a pipette tip of 5-7 microns (that's 60 times thinner than human hair) to puncture the zona. The mechanical method is a time-consuming, laborious procedure and highly dependent on the skills of the doctor-technician. Besides, both methods carry the risk of injuring or damaging the embryo itself.

The LAH allows a touch-free access to the zona and does not move the embryo significantly either. Also, patients do not spend money on repeated IVF or MM procedures. As did softwareprofessional Kalpana last year when she went through two IVF/MM procedures. Married for nine years, she lost heart when the second procedure too failed. Her problem was diagnosed as thick zona. ``At that point, I had given up all hopes of ever carrying a baby,'' she said. Then she happened to be in the first LAH batch in Jaslok. Five weeks pregnant, Kalpana cannot thank laser technology enough. Other super-speciality hospitals in Mumbai are preparing to offer the LAH method too.