IT IS not quite do-it-yourself IVF, but it is close. An INVOcell, brainchild of Claude Ranoux of INVO Bioscience, in Medford, Massachusetts, is a device that allows a woman employing it to use her own body as an incubator for the embryos she hopes to have implanted, rather than relying on a machine to do the job. Several trials have suggested it is safe, and could be as effective as conventional IVF—and it has already been approved for use, in certain circumstances, in Europe, and in parts of the Middle East and South America, though not yet in the United States.
The latest trial, presented to the American Society for Reproductive Medicine’s annual meeting, in Honolulu, on October 22nd, by Kevin Doody, of the Centre for Assisted Reproduction, in Bedford, Texas, and his colleagues, indicates that it could be cheaper than conventional IVF, too. Dr Doody has refined the way INVOcells are used, to create a method that could halve IVF’s cost.
The first part of Dr Doody’s method streamlines the process of egg collection. At the moment, this is laborious. First, a clinic’s doctors check their patient every few days, to see how her eggs are coming along. That means taking ultrasonic scans of her ovaries and monitoring her hormone levels. Based on the results, the doctors may then tinker with the dose of egg-stimulating drugs she is receiving.
Dr Doody thinks, though, that this complex arrangement may be unnecessary for about two-thirds of women. Instead, he administers a “conservative” (ie, on the low side) dose of the egg-stimulating drugs, which is based on a woman’s body weight and a single blood test that measures her capacity to produce good eggs. One subsequent ultrasonic check is enough, he says, to confirm whether an egg harvest is possible, and, if so, when. Besides being simpler for the patient, this arrangement is obviously cheaper than the established way of doing things.
Once the eggs are harvested, they are introduced to sperm from the woman’s chosen donor, as happens in conventional IVF. But after that, the INVOcell takes over. An INVOcell is a cylindrical contraption about 4cm long and 3cm in diameter, made of gas-permeable polystyrene. It consists of two concentric chambers, an arrangement intended to protect the contents of the inner chamber from bacteria. After a couple of hours in a Petri dish, the eggs—still unfertilised, but with a penumbra of hopeful sperm clinging onto them—are placed in the inner chamber. The whole thing is then popped into the mother-to-be’s vagina, where fertilisation and early embryonic development take place.
The IVF incubators in which this normally happens are expensive and complex electromechanical devices which require calibration and careful management of temperature, carbon dioxide, oxygen and the like. And they can malfunction, so they have be fitted with alarms and monitored continuously. An INVOcell gets around all this by using the putative mother’s own body to provide the necessary homeostasis for the eggs to thrive.
Standard IVF procedure is to incubate embryos for five days before they are implanted into the mother’s womb. Previous trials of INVOcells have left the embryos in the device for only three of those days, then retrieved them and either implanted them early (which is less effective) or finished the process in a conventional incubator. Dr Doody, however, has kept them there for the full five days. That makes incubators redundant—another cost saving.
Importantly, Dr Doody’s method seems to be as effective as the conventional approach. Of an admittedly small sample of 37 infertile women in his study, two-thirds became pregnant after a single incubation, regardless of which method was employed. If bigger trials confirm Dr Doody’s results, then many more infertile women than now will find the cost of IVF within their reach.