Sperm cells need to undertake an arduous journey that can take hours through the female reproductive tract before one of them fertilises a waiting egg. Now, scientists have developed an instrument that may help find the most likely winners in this race. Virtually all existing sophisticated semen analysis and sperm monitoring machines measure the horizontal speed of the sperm. “In the reproductive tract, sperm cells need to move at least part of the time against gravity,” says Gopal Mazumdar of the Indian Institute of Chemical Biology, Calcutta. The researchers have combined light sensors, glass tubes and a computer to develop an instrument that can measure the vertical velocity of the cells. “The higher the vertical velocity, the healthier are the sperm cells,” said Sudipta Saha. But the scientists also caution that a correlation between vertical velocity and fertility is yet to be established.

Microwave test

A simple urine test is all that is required to determine pregnancy in minutes. But Kattackal Thomas Mathew of the Cochin University of Science and Technology and colleagues have just shown that microwaves may instead be of help — to study the electrical properties of the urine of pregnant women, as conductivity of urine is higher during pregnancy than otherwise. Also, the technology could have greater potential in the diagnosis of tumours. The difference in the electrical properties of tumours and normal tissues is significant enough for this technique to find use in cancer diagnosis, Mathew said.