Ash Semione's path to becoming a gestational surrogate began when her brother and sister-in-law struggled to have children. After doing extensive research, she offered to carry the couple's biological child to help them overcome fertility issues. 

She didn't end up carrying her brother's child, but the discussion introduced her to the world of gestational surrogacy: when a woman carries a fetus conceived without her own egg to term and gives birth to the baby. Her curiosity ultimately led to a career change for Semione. 

"By then, I had done so much research I felt like I had to do this at least once," she told CBS MoneyWatch. 

Semione, who has two kids of her own, was a stay-at-home mom when she decided to become a gestational surrogate for another couple. 

She earned $55,000 in base pay to carry the couple's child, whom she calls her "belly bud." She was also given a monthly allowance to cover incidental expenses like maternity clothing and costs associated with commuting to pre-natal appointments. 

While a number of high-profile celebrities have drawn attention to the practice of hiring gestational surrogates, the approach isn't without critics. Among them is Pope Francis, who earlier this month called it "deplorable" and called for a universal ban. The pope said it amounts to the "commercialization" of pregnancy and exploits mothers and children. 

Surrogacy "represents a grave violation of the dignity of the woman and the child, based on the exploitation of situations of the mother's material needs," he said.

Yet people who work in the industry says it helps people become parents who might not have otherwise been able to have children. And women who work as gestational surrogates note that they are driven by the ability to help others.

"I wanted to help somebody"

Semione said her initial motivation was simple. "I wanted to help somebody, be able to give something to somebody after watching someone else struggle," Semione told CBS MoneyWatch. "The compensation was not the driving factor for me, because I went into it well aware of what I was getting into, having seen family struggle and understanding what in-vitro-fertilization entails. It's no easy feat."

But the money was "wonderful and life-changing," Semione said, adding, "It wasn't the reason why I started it, but it's a wonderful addition to everything else." 

The money she earned in exchange for being pregnant allowed her to make upgrades to her home, contribute to her savings account, and pay off debt.

The experience was career-changing, too. 

Semione, who holds a degree in finance, said she had planned on a career in that field before having her own kids. 

But after her first journey as gestational surrogate, she saw a different path for herself. Since then, she has been working as a surrogacy outreach specialist for Surrogacy Is, an organization that matches surrogates with couples, or intended parents. 

"I've completely shifted careers and can't imagine doing anything else," Semione said. 

Three-time surrogate 

Sunshine Hanson, co-founder and president of Surrogacy Is, was looking to supplement her income as a high school English teacher, without adding many more hours of work to her already packed schedule, when she discovered gestational surrogacy. 

"I was looking for something meaningful I could do that wouldn't take up a lot more time like a part-time job would," Hanson told CBS MoneyWatch.

Through a surrogate agency, she matched with a pair of dads for whom she delivered twins. 

She earned $28,000 in base compensation, plus an additional $10,000 for carrying to term two children at once.

"I definitely got more than I expected out of that journey; it was such a rewarding and fulfilling experience," Hanson said. "What I was initially doing just for second income stream ended up being so much more valuable than that."

Hanson has since carried two more children for another couple, earning $75,000 per pregnancy. 

Her earnings allowed both Hanson and her husband to jumpstart their small businesses, pay off student loan and credit card debt, and put money into their retirement accounts.

"We don't have any debt and without surrogacy that wouldn't be true," Hanson said. 

While the money is good — Hanson has earned six figures as a gestational surrogate for one couple — "it's definitely not something you can do for the sole purpose of a side hustle if you need additional income," she said. 

She noted the risk of pregnancy-related complications, as well as the toll that even a normal, healthy pregnancy can take on the body, including postpartum. 

"If you are doing it solely for the purpose of earning money, I don't think there is any amount of money worth it, if that's your sole motivation," Hanson said. 

Are there requirements for surrogacy?

To be eligible, women must be at least 21 years old and have already given birth to a child. Additionally, prospective surrogates must pass medical and psychological exams. 

Solveig Gramann, director of surrogate services for Circle Surrogacy, a New York-based surrogacy agency, described the rigorous screening process that's involved.

"We make sure they are in a stable position in life and that they have appropriate education as to whether or not they want to do this in first place," she said. 

Each month, about 1,000 women start applications to become gestation surrogates through Circle Surrogacy, but only 40 to 50 make it through the screening process, Gramann added. 

On average, nationwide, base pay for first-time surrogates is between $45,000 and $55,000, with fees rising to between $60,000 to $70,000 for second-time surrogates, according to Gramann.

The cost to those families using a surrogate is even greater, typically around $150,000, when additional expenses are factored in. 

For this reason, intended parents typically earn higher incomes than the surrogates they match with, who oftentimes are nurses and teachers, or hold administrative positions. 

"We see plenty of nurses who are attracted to surrogacy because they like to help people," Gramann said. 

How does surrogacy work?

Denise Patton, an Illinois-based surrogacy attorney, said surrogacy has become more popular as a path to parenthood over the course of her 25-years practicing. 

"My caseload has increased significantly," she said.  

Legal contracts that govern surrogacy arrangements are often 40 pages long to ensure all parties are protected. 

"Unless you have a really good friend or relative that's willing to do it without compensation, you have to be in a position to cover their lost wages and child care if they're on bed rest, homemaker skills if they are on bed rest and can't do laundry and clean their house for their children. We try to think of all those types of things because you don't want any bad or hurt feelings."

The rising costs have also priced some prospective parents out of surrogacy as a route to parenthood. 

"Compensation of surrogates has really jumped in the last couple of years," Patton said. "I feel bad because it's pricing some families out of that option."

Megan Cerullo

Megan Cerullo is a New York-based reporter for CBS MoneyWatch covering small business, workplace, health care, consumer spending and personal finance topics. She regularly appears on CBS News streaming to discuss her reporting.