Costs for maternity coverage could soar under the current GOP Senate health care replacement bill, the Better Care Reconciliation Act, according to a study by the March of Dimes and Avalere.

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The analysis illustrates the impact with a hypothetical: Kate, 30, pregnant, self-employed and enrolled in an insurance plan on HealthCare.gov because her husband’s employer-provider insurance doesn’t extend to family members. Kate pays an annual premium of $2,952 for her Affordable Care Act plan, and her share for maternity care is $4,100 out of the $7,540 total cost for the birth of her child. If there are complications at birth, the maximum amount Kate would pay would be $7,150.

However, if maternity care is not included as an “essential benefit” (per the GOP plan), Kate would have to purchase another plan which does have maternity coverage. That could be anywhere from 25 percent to 70 percent more expensive than the plan she has now, with an annual premium as high as $4,452. Kate would have to pay completely out-of-pocket if there are any complications at birth.

Moreover, if Kate couldn’t get a plan with maternity coverage, her out-of-pocket cost would be $15,000 and would be much higher if there are complications. Meanwhile, the annual premium for such a plan would be $120 less than her ACA plan on the exchange -- about 10 percent less each month.

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“Our study shows the cost of having a baby could escalate drastically under the changes proposed in the Senate health care bill -- and that’s for having a healthy baby,” says Stacey D. Stewart, president of the March of Dimes. “If a woman has pregnancy complications, or the baby is born sick or prematurely, health care costs could skyrocket even further.”

The changes proposed by the Senate could return the individual health insurance market to the pre-2010 status quo, when maternity care was excluded from most plans or offered only as a costly rider, according to the study. Prior to the Affordable Care Act’s requirement that all plans cover maternity and newborn care, only 13 percent of plans routinely did so.

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“We need to do more to prevent preterm birth because it’s the leading cause of death among babies in this country, and can lead to long-term health problems and lifelong disabilities,” Stewart says. “But in fact, federal government data released in July show that preterm births actually are on the rise. There was an alarming 2 percent increase in the preterm birth rate between 2015 and 2016. Now is not the time to make it more expensive for a woman to get the prenatal care she needs for her own and her baby’s health.”