Eighteen months ago, Ms Curtiss welcomed news of a planned review of fertility policy across the East Midlands.
There are five integrated care boards providing fertility services and, at present, most policies require that neither partner has living children. The review aims to create one policy for the whole region.
Ms Curtiss previously said she had received assurances that the rule regarding stepchildren would go.
However, she said she felt “disappointed” and “let down” after reading the proposals for the updated guidelines.
Ms Curtiss, who is now pregnant, said she would continue to fight for other step-parents who needed support to have a child.
“If anything, this pregnancy has spurred me on”, she said. “To know I’m going to be a mum is a magical experience and I want others to have that feeling.”
A spokesperson for NHS Lincolnshire Integrated Care Board said: “We are conscious of the strength of feelings around fertility treatments and any proposals made around them, and this is why we are asking people to complete our survey, external and share their views, which will feed into the final policy.
“It is important to emphasise that, whilst we have put forwards a proposal, no decisions have been made.”
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