“It is a lot of money,” says Emma Jane. She’s now planning to undergo a second cycle – doctors recommend women have 20 for the best chance of having a live birth. Storing her eggs will also cost Emma Jane an additional £360 annually, which will set her back thousands if she stores them for the UK’s maximum term of ten years. Then there is the cost of IVF itself, which can run to £5,000 or more for private treatment, if she chooses to use them.

The costs can become astronomical. Emma Jane compares it to “an insurance policy that could be a waste of money, because I might meet a partner and have kids naturally”.

“Even if I met someone tomorrow who was the man of my dreams, it would be a while until we settled down and got married. Then if we chose to have a kid, I’d probably be 40 by then, and if I wanted two kids, I’d probably be in my early 40s.”

But what these women are paying for is still just a sliver of hope. The technology is not guaranteed to work, since the majority of IVF cycles end in failure – only a fifth are successful – and there is always the chance that the frozen eggs might not survive the thawing process, or could have chromosomal abnormalities.

Helaine Olen, a personal finance writer and author of personal finance book Pound Foolish, questions why so much money is pouring into an industry that still has low success rates. “This is about American women getting sold on a less-than-certain technology as a way of addressing greater sociological issues,” argues Olen.

And for most women, they hope they will meet a partner and get pregnant the old-fashioned (and free) way, and therefore never having to use their frozen eggs at all.

Tiffany Murray, now 40, froze her eggs when she was 34 after having limited success with dating in Washington, DC. Rather than be pushed into a relationship that wasn’t right by the desire to have children before it was too late, she chose to freeze her eggs. Her parents paid for the procedure as a Christmas gift.

Four years later, however, she met her now-husband and they conceived naturally shortly after they were married. She still pays to keep her 14 frozen eggs stored in case they have trouble conceiving a second time; in the six years since she froze, the annual storage fee has risen from $350 to $600.

At that price, jokes Murray, it feels a little like her “eggs are being held to ransom”.

Despite the high cost of retrieving 30 of her eggs and the $1,000-a-year storage fees, Nadine feels she made the right choice. She even encourages friends to consider freezing their own eggs.

“There’s a little bit of anger surrounding the finances,” she says, but she adds that she does not regret making the investment in her future.

“Now I have 30 kids on the Upper West Side that I pay $1,000 a year for,” she adds with a laugh. Or at least she might have, if she ever chooses to cash in her fertility insurance policy.

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* Nadine's name has been changed to protect her identity. Emma Jane asked not to give her full name for this article also to protect her identity.

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