High Cholesterol Linked to Infertility, Study Finds
High cholesterol, which is caused by plague buildup in the artery walls, can be extremely dangerous for heart health. Too much buildup makes it hard for the body to circulate blood, which can lead to a stroke or a heart attack. In a new study, researchers found another health consequence of having high cholesterol. The team tied high levels to infertility risk in both men and women.
"From our data, it would appear that high cholesterol levels not only increase the risk for cardiovascular disease, but also reduce couples' chances of pregnancy," said Dr. Enrique Schisterman, chief of the Epidemiology Branch at the Eunice Kennedy Shriver National Institute of Child Health and Human Development at the National Institutes of Health (NIH), reported in CBS News.
The researchers from the NIH, the University of Buffalo and Emory University monitored 501 couples that were a part of the Longitudinal Investigation of Fertility and the Environment study. That study, which lasted one year, examined the effects that environmental and lifestyle factors might have couples' health and fertility. In the latest study, the couples were all from Michigan or Texas and had been trying to conceive naturally. The women were between the ages of 18 and 44 and the men were all older than 18. Over the year, 347 couples became pregnant.
The researchers collected data on each participant's cholesterol levels, which included HDL (high density lipoprotein) cholesterol, LDL (low density lipoprotein) cholesterol and triglycerides via blood samples. With this information, the team used a mathematical formula called the fecundability odds ratio, which estimated each couple's chances of getting pregnant as well as the amount of time it would take.
The team discovered that women with higher levels of free cholesterol were less likely to get pregnant within the time frame of the study. The researchers found that even if the man had normal cholesterol levels, the couple's chances of getting pregnant still fell if the woman had high cholesterol. The team looked at free cholesterol, which is cholesterol that is not bounded to another molecule.
"We found a relationship between high free cholesterol levels and a longer time to pregnancy in couples," said Schisterman reported by FOX News. "This is the first study to look at cholesterol levels in both partners at the same time, and their influence on the probability of becoming pregnant."
The study was published in the Journal of Clinical Endocrinology and Metabolism.