Hormone tests not working for women’s fertility

The main reason for the decline in fertility with advancing years is the decline in the number and quality of eggs in a woman’s ovaries. unlike men, who sperm formation Throughout life after puberty, although in ever-decreasing amounts, all of a woman’s potential eggs develop when she is still a fetus. In a newborn girl, their number is more than 1 million. By puberty, he has about 400,000 left. When menopause occurs, this is reduced to less than 1,000, which is likely to be very low.

But currently offered fertility tests neither count the number of eggs remaining nor assess their quality. Instead, they rely on an indirect approach – sampling what is expected to be the relevant hormone. Hormone tests have some value in predicting the timing of menopause and the success of egg collection for in vitro fertilization. But predicting pregnancy? The evidence suggests that they cannot do this.

One test-skeptic is Anne Steiner of the Duke Fertility Center in North Carolina. He suspects that the hormone test reveals how many eggs a woman has left, but that doesn’t matter—rather, it’s the quality of the eggs that’s important.

Between 2008 and 2016, Dr. Steiner and colleagues ran the Time to Conceive study. The aim was to determine whether hormone levels could actually predict a woman’s fertility independent of her age. The team then found that those levels had no significance in predicting pregnancy in the year following the test. Now, in a follow-up to the original investigation published in Fertility and Sterility, Dr. Steiner has shown that they also lack the power to make long-term predictions.

Time to Conceive looked at 750 women aged 30 to 44 who were living with a male partner who was not infertile, had no diagnosis of infertility, and had recently started trying to become pregnant. The team took blood and urine samples from these volunteers and measured the levels of three hormones often measured by fertility tests. Then they followed each volunteer for a year. The findings, published in 2017, were that hormone levels were uncorrelated with pregnancy within the 12-month period the researchers were looking through.

But perhaps, Dr. Steiner later surmised, that window was too narrow. So in 2020 she got back in touch with the original participants for a follow up. She asked them if they would fill out a questionnaire asking how many children they had, how long it took to become pregnant, and whether they had been diagnosed with infertility.

About 336 of them agreed to participate. Of these, 239 pregnancies resulted in 225 live births. More sadly, 73 of the participants were infertile. But the hormone levels in the tests done in the original study did not predict these outcomes. The researchers found that there was no difference between women with poor results and women with normal results.

In the case of one substance, for example—anti-Mullerian hormone, which is thought to be prognostic because it is produced by cells in the egg-producing follicles of the ovary, and thus thought to reflect the number of follicles in those follicles—79% of those with low levels go on to have a baby. It was statistically indistinguishable from the 71% of mothers with normal levels. Dr. Steiner says that the decline in fertility is not clearly related to a decline in the quantity of eggs, but is probably related to their quality. And how to measure it is unknown.

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UPDATE: July 21, 2023, 02:41 PM IST