Four lesbian women are suing the head of a New Jersey agency over a state mandate that requires health insurers to cover fertility treatments for women under 35 only after couples have had two years of unprotected sex.

The New York Times reports that Erin Krupa, one of the women bringing the suit, was diagnosed with uterine cysts and endometriosis in 2013, when she was 33 and beginning the process of getting pregnant with her wife. Her doctor told her not to worry, since New Jersey is one of 15 states that require insurers to cover fertility treatments. That’s when Krupa found out that her insurance provider, Horizon Blue Cross Blue Shield, would only pay for treatments under the conditions required by the state’s 2001 mandate.

Under the current rule, a woman must prove her infertility through two years of unprotected sexual intercourse if she’s under 35, or one year if she’s 35 or older, to get guaranteed coverage. The New Jersey mandate does not account for the fact that failing to make an embryo through unprotected gay sex doesn’t make anyone more or less fertile. In fact, the rule defines sexual intercourse as “sexual union between a male and a female” and infertility as “a disease or condition that results in the abnormal function of the reproductive system” such that a male can’t impregnate a female, either partner is medically sterile, the female can’t carry a pregnancy to term, or she can’t get pregnant in one or two years of straight sex.

A literal interpretation of this mandate leaves behind gay people or single straight people with normally functioning reproductive systems but a lack of all the biological doodads necessary to make a baby. (Insurance companies have also denied fertility treatment coverage to single people, resting on laws that only guarantee treatments that use a spouse’s sperm.)

The lawsuit the Krupas and two other women are bringing against the commissioner of the New Jersey Department of Banking and Insurance claims that this mandate discriminates against gay people by forcing them to pay out of pocket when they are certain to need fertility treatments, regardless of their age. Of the states that require insurers to cover fertility treatments, only California and Maryland have changed the language in their mandates to encompass patients and couples of all sexual orientations. There are two bills pending in the New Jersey state legislature that would leave it up to a physician to determine if a woman or couple is facing infertility, but they’re still in committee.

This move would do right by straight couples, too. Forcing couples to prove infertility by having a year or two of sex without getting pregnant is medically unsound policy. Many cases of infertility can be explained by diagnosable medical conditions: low ovarian reserve, low sperm motility, hormonal imbalances, abnormal levels of cervical mucus. If a doctor evaluates a patient and determines that she’s unlikely to get pregnant without medical assistance—as Krupa would have been, even with a cis male partner—wasting two years before getting started would cause needless frustration.

It would also decrease her chances of getting pregnant, an important consideration for insurance companies that presumably don’t want to have to pay for more rounds of treatments than they have to. Once a woman hits age 35, she becomes increasingly less likely to get pregnant with every passing year. Between age 34 and ages 35-37, the chances of a live birth resulting from a cycle of assisted reproductive technology drops 8 points. Between 34 and 38-40, it drops 19 points. Statistics show that a woman’s chance of getting pregnant from an ART cycle starts dropping around age 28 and accelerates around age 31. One or two years of unprotected sex is precious time wasted. And that doesn’t even take into account the risks of miscarriage, complications, and fetal chromosomal abnormalities, all of which increase as a woman ages.

In a statement, Horizon told the Times that it covers “infertility services equally, regardless of sexual orientation.” That’s the problem: Opposite-sex couples and same-sex couples do not face equal barriers to reproduction. To paraphrase the immortal words of the electro-pop band MEN, two cis women can fuck their best, but they’ll never produce a little tiny baby. For an agency that can wrap its head around the minute details of ovarian functioning and egg fertilization, the New Jersey Department of Banking and Insurance knows shockingly little about the birds and the bees.