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Up to 15% of couples struggle to conceive. But did you know that male partners contribute to about half of infertility cases?

Semen analysis, the main diagnostic tool for men, has long fallen short in accurately predicting male fertility. A newer sperm test could change that dynamic and help guide couples’ reproductive choices. Summit Health urologist Eric Seaman, MD, helps explain the Cap-Score™ test and what it can mean for couples trying to get pregnant.

What is the Cap-Score test?

The Cap-Score test measures capacitation, or a sperm’s ability to fertilize an egg. Capacitation is a series of maturational changes sperm must undergo to get through an egg’s outer wall and begin fertilization. By measuring sperm’s functional ability, the test can help predict the odds of achieving pregnancy.

“Research found that the higher the percentage of sperm’s ability to capacitate, the more likely it can fertilize,” says Dr. Seaman.

How are Cap-Score and semen analysis tests different?

Both tests involve lab analysis of a semen sample. Semen analysis looks at multiple factors, including:

  • Count – the number of sperm in a sample
  • Concentration – the number of sperm per millimeter of semen
  • Morphology – the size and shape of sperm
  • Motility – the percentage of sperm swimming toward an egg

However, semen analysis doesn’t measure capacitation. “Cap-Score is the missing piece of that logical sequence,” says Dr. Seaman, who offers the test alongside semen analysis.

What studies on Cap-Score found

Researchers looked at Cap-Score’s ability to predict male fertility. They compared men predicted to have either a low or high chance of generating pregnancy based on defined Cap-Score ranges.

The study’s results were encouraging. Pregnancy was achieved within three cycles of intrauterine insemination (IUI) — a procedure that uses a cannula or tube to place healthy sperm inside the woman’s uterus. Men predicted to have a high chance of pregnancy succeeded at a rate nearly three times higher than men with a predicted low probability.

So, what does this mean? Male fertility is not black and white, explains Dr. Seaman. Instead, it exists in degrees and is influenced by many factors. And Cap-Score can add more clarity to a couple’s next steps.

How can test results help couples?

Infertility can be emotionally, physically, and financially demanding for some couples. When used with semen analysis and thorough medical exams of both partners, Cap-Score can help better personalize fertility plans.

For example, a provider may encourage a man with a high Cap-Score to try IUI.

Conversely, a man with a low score may want to consider in vitro fertilization (IVF) with intracytoplasmic sperm injection, a modification of IVF often used in male infertility cases. 

Additionally, test results may help guide treatment to improve the male partner’s fertility, such as lifestyle changes, medication, or surgery. 

Dr. Seaman says he doesn’t encourage Cap-Score testing for men with very low sperm counts, but it doesn’t close the door on treatment. “It doesn’t mean there isn’t hope,” he says. “There are many options available. We encourage anyone who is struggling to conceive to come in for an appointment and we will identify a plan that is right for them.”

Talk to your provider if you and your partner have been trying unsuccessfully to conceive for more than one year. In addition to your individual medical evaluations, a urologist with expertise in male infertility can help.