Around 1 in 8 couples in the US have problems getting pregnant or sustaining a pregnancy, and around a third of these cases are attributable to the female partner. Most infertility cases are treated with medication or surgery, but when these fail, assisted reproductive therapies - such as IVF (in vitro fertilization) - become an option.
Researchers say a naturally occurring hormone - kisspeptin - is safer than the hCG hormone for boosting ovulation in women undergoing IVF.
IVF involves manually inserting sperm into an egg in a laboratory dish. If fertilization is successful, the embryo is then physically placed in the uterus. Prior to this procedure, patients may be required to take injectable fertility drugs - such as a hormone called hCG - to trigger egg production.
But the research team, led by Prof. Waljit Dhillo of the Department of Medicine at Imperial College London in the UK, notes that as a result of such drugs, some IVF patients experience ovarian hyperstimulation syndrome (OHSS).
OHSS is a condition that triggers overstimulation of ovaries, causing them to become swollen and painful. In some cases, women may experience rapid weight gain, shortness of breath, abdominal pain and vomiting.
"OHSS is a major medical problem," says Prof. Dhillo. "It can be fatal in severe cases and it occurs in women undergoing IVF treatment who are otherwise very healthy."
Kisspeptin results in 'good outcome' compared with standard IVF treatment
For their study, Prof. Dhillo and colleagues tested a naturally occurring hormone called kisspeptin on 53 women undergoing IVF to see whether it could trigger ovulation induction in a safe and effective manner.
After each woman received one injection of kisspeptin, 51 out of 53 developed mature eggs, and 49 had either one or two fertilized embryos that could be transferred to the uterus. Of these women, 12 became pregnant, which the researchers say is a "good outcome" when compared with standard IVF therapy using hCG.
One of the participants, Alison Harper, gave birth to a baby boy, Owen, in October last year. She says that after several cycles of IVF, the one used in this study was the least uncomfortable, causing less pain and swelling.
The research team explains that kisspeptin does not stay in the blood for long periods like hCG. This means the hormone is broken down faster, reducing the occurrence of ovary overstimulation.
Commenting on the team's findings, Prof. Dhillo says:
"Our study has shown that kisspeptin can be used as a physiological trigger for egg maturation in IVF therapy. It's been a joy to see 12 healthy babies born using this approach. We will now be doing more studies to test whether kisspeptin reduces the risk of OHSS in women who are most prone to developing it, with a view to improving the safety of IVF therapy."
The researchers now plan to conduct a second study among women with polycystic ovary syndrome, who have the highest risk of OHSS as a result of treatment with fertility medication.
Medical News Today recently reported on a study published in Nature Communications, which detailed how deep-freezing testicular tissue could be a promising technique to preserve fertility among boys who undergo treatment for cancer.