Indian scientists have made a major discovery that could help improve pregnancy rate, especially for couples struggling with infertility. They have found a key “genetic switch” that allows an embryo to attach itself to the lining of the uterus, which is the first and most important step for pregnancy to begin. This research has been published in the international journal Cell Death Discovery.

The study was conducted by teams from the ICMR–National Institute for Research in Reproductive and Child Health (NIRRCH), Mumbai, the Indian Institute of Science (IISc), Bengaluru, and Banaras Hindu University (BHU), Varanasi. 

For pregnancy to occur, the embryo must settle and attach to the uterus lining in a process called implantation. If this process fails, pregnancy cannot continue, even if the embryo is healthy. Implantation failure is one of the major causes of infertility and early pregnancy loss, and it is also a common reason why IVF treatments do not succeed.

The researchers found that two genes, HOXA10 and TWIST2, control whether the uterus is ready to receive the embryo. Under normal conditions, HOXA10 keeps the uterus lining firm, stable, and closed. But exactly at the moment when the embryo reaches the uterus and makes contact, the activity of HOXA10 drops temporarily. When this happens, TWIST2 becomes active, making the uterine cells softer and more flexible so the embryo can gently attach and settle in.

The study also showed that HOXA10 controls more than 1,200 other genes that help maintain the closed and protective state of the uterus lining. When HOXA10 levels decrease, the lining goes through a controlled transformation that increases cell movement just enough to support implantation without causing any damage. Mathematical models created by IISc scientists confirmed that HOXA10 and TWIST2 work like a reversible switch that turns the uterus “ready” or “not ready” for pregnancy.

To prove its importance, scientists tested what would happen if TWIST2 was blocked in mice. They found that the uterus could not remodel, and implantation did not happen at all. This experiment confirmed that the genetic switch is essential for pregnancy to begin.

This breakthrough could help doctors develop better treatments for infertility, especially for women undergoing IVF. It may also lead to new research in areas like wound healing, tissue repair, and cancer, where cell remodeling plays a major role.