Journalist Sarah (44) dreams of having a child, while TV producer Susanah(38) is waiting for her younger boyfriend to be ready to have children.
To keep their hopes alive, these New York women have spent tens of thousands of dollars on freezing their eggs in a practice that has become increasingly popular.
Facebook recently began covering costs of egg freezing for employees and Apple will do the same starting in January.
Susanah jokes of taking advantage of the progress in medical science as an "insurance policy" even if the chances of conceiving are still stacked against her.
The younger the woman, the more fertile her eggs, and fertility drops rapidly after 35. So women freeze their eggs while there is still time, in order to use them later.
Sarah Elizabeth Richards was one of the first to take advantage of the technique, which the American Society for Reproductive Medicine considered experimental until 2012.
She froze her eggs eight times between the ages of 36 and 37, first in Canada where it was cheaper, and then in New York.
She has put aside 70 eggs, she told AFP in her tiny apartment in Manhattan's Upper West Side.
She used her savings. Her parents helped out. In total, she spent $50,000.
"It is an extreme amount of money to spend on something like this, but I always knew I wanted kids," she said, adding that she is still looking for the perfect man.
"And when I thought, 'where could I spend the money? A house, a vacation or a chance to have a family?' it seemed like a very easy choice."
- Sense of relief -
She has written a book called "Motherhood Rescheduled: the New Frontier of Egg Freezing and the Women Who Tried it" and said putting aside her eggs gave her a "profound sense of relief."
She knows her chances are slim but still hopes to have a child in the next two years by thawing the eggs and having in-vitro fertilization, which would cost thousands of dollars more.
She said egg freezing should not be done for the sake of a career, but welcomes debate about the problems of juggling a family and a career in a country where that is still difficult.
"Child care, maternity leave, this is a big American problem, but the answer is not to delay motherhood," she said.
Susanah, a graphic design producer for TV, also froze her eggs between 36 and 37, after hearing about it "around the water cooler" at work and because she does not feel ready to have kids.
But she gets angry when people talk about women delaying a family for the sake of their career.
"Dating is notoriously terrible in the city. I have many friends who are successful, beautiful, in their late 30s and single," she said.
"If they had met the guy five years ago, they would have."
The fact that her boyfriend is 11 years younger also played a role in Susanah's decision.
"It gave him a peace of mind too, because he is dating a woman right at that age where the biological clock is ticking."
Twice she has undergone two weeks of hormone injections to ripen multiple eggs, which are then harvested by surgical intervention.
- False hope? -
"It takes time, it is uncomfortable and time-consuming, but it is worth it," she said, proud to talk about it even if she does not want to give her family name.
It cost $16,000 each time and while she says at first she was hesitant about the expense, she was persuaded by a friend that freezing her eggs was worth her savings.
"A friend told me 'you have your whole life to pay for a mortgage, you don't have your whole life to do that.'"
She is giving herself five years.
"When we decide, I will try naturally and then, if that doesn't work" she will think about resorting to the frozen eggs.
Even in 2012, when ASRM decided the technique was no longer experimental, it still did not recommend the procedure.
"Marketing this technology for the purpose of deferring childbearing may give women false hope and encourage women to delay childbearing," it said in a report.
But demand has only increased, said Sheeva Talebian, a fertility specialist at Reproductive Medicine Associates New York, which describes egg freezing as a "revolutionary technique."
New York University Fertility Center director Jamie Grifo said success rates are "relatively equivalent" to in-vitro fertilization.
He puts them at 55 percent for a 30 year old, 27 percent for a 40 year old, 15 percent at 42 and six percent at 44.
But the procedure is never foolproof, Grifo said.
"This is a hope, not a promise."