Anyone who's ever struggled to get pregnant knows how incredibly heartbreaking it can be. Every month without a positive pregnancy test is agony. Luckily, for most women it will happen eventually, even if it takes a lot of trying and a lot of patience. Sadly, others won't get to experience the joy of motherhood without some help. Some couples who want a biological child will turn turn to a surrogate— a woman who carries another couple's baby.

Infertility doesn't discriminate, so even celebrities with all the money in the world suffer from it as well. Plenty of them have chosen surrogacy, and some have been more candid about it than others. Some stars have talked openly about year-long struggles with infertility, while others have kept their reasons private. While gossip magazines may love to speculate about what led to the decision (is it age? is it vanity?), it's an intensely personal matter that I can't blame some stars for staying quiet about. But those who do go public with their journeys can provide so much hope and comfort to couples still struggling to start a family.

Here are 15 stars that turned to surrogates to help them become parents.

15 Ellen Pompeo

Grey's Anatomy star Ellen Pompeo and husband Chris Ivery started their family in 2009 with the birth of their daughter Stella. But when it came time to expand their brood, Pompeo turned to a surrogate for baby number two. She and Ivery welcomed daughter Sienna May in 2014. Pompeo waited until after she'd brought her little girl home to announce that she'd used a surrogate.

Discussing her second-born on Jimmy Kimmel Live, she said she'd kept the pregnancy under wraps to protect the surrogate's privacy. She said she was able to undergo egg retrieval so her daughter is hers biologically, even though she was unable to carry her. Pompeo and Ivery have since added another child to the family, though they haven't commented on whether they used a surrogate again.

14 Tyra Banks

Former supermodel and America's Next Top Model host Tyra Banks took to Instagram last year to reveal that she'd welcomed a baby boy. In a sweet caption, she expressed her gratitude to the surrogate that helped her become a mom: "As we thank the angel of a woman that carried our miracle baby boy for us, we pray for everyone who struggles to reach this joyous milestone."

Banks and her boyfriend Erik Asla had tried to conceive naturally and had even turned to IVF, with no success. Banks, who is 43, had lamented that her age had made the process of conceiving even more difficult. But with the help of modern science and an assist from a surrogate, York Banks Asla was born happy and healthy. No word yet on whether she'll be looking to add a sibling to the family.

13 Elizabeth Banks

Hunger Games star Elizabeth Banks has been vocal about her struggle with infertility and the role of her surrogate. Banks told Lucky magazine that embryos simply wouldn't implant in her uterus, making it extremely difficult if not impossible for her to get pregnant on her own. When she and husband Max Handelman decided to start their family, a surrogate helped them welcome son Felix in March 2011.

A second son, Magnus, quickly followed in 2012 once again with the help of a surrogate. Banks has said she and her family have remained close to their carrier, saying she's become like an aunt. Despite the disappointment of not being able to get pregnant herself, Banks said the experience of using a surrogate taught her a lot of about gratitude and generosity.

12 Amy Smart

Amy Smart and her husband Carter Oosterhouse got the best Christmas present ever in 2016: a baby girl born via surrogate. Smart took to Instagram on New Year's Eve that year to announce that daughter Flora had arrived on December 26. Proud dad Oosterhouse also chimed in with a post of his own telling his little girl, "We love you more than you know and can't wait to experience the journey. What a blessing."

It came as a surprise to some fans, who hadn't even realized that Smart and her HGTV star husband had been expecting a bundle of joy. The happy new mom showed off her gorgeous daughter again on Instagram about a month later, thanking the woman who carried her to term. Smart said she was so grateful to finally have a baby "after years of infertility struggles."

11 Sarah Jessica Parker

Sex and the City star Sarah Jessica Parker and husband Matthew Broderick started their family with son James Wilkie in 2002. SJP's pregnancy coincided with the filming of her hit HBO show, and it actually caused season 5 to be shortened. After one successful pregnancy, however, the couple struggled to conceive again. After trying for years to get pregnant on their own again, Parker and Broderick turned to a surrogate.

They welcomed twin daughters Tabitha Hodge and Marion Loretta in 2009. But what should have been a time of pure joy turned into a bit of a nightmare for the star couple and their surrogate, after she was identified by tabloids and hounded for information, and even had her ultrasound pictures stolen— by none other than her town's police chief.

10 Nicole Kidman

Nicole Kidman's journey to motherhood has taken her down many different roads. She was just 23 when she married fellow actor Tom Cruise and the two started a family, adopting daughter Isabella and son Connor. After the two divorced and Kidman eventually found love again with singer Keith Urban, she decided to have more children. Her struggles with infertility led her to question whether she would ever experience pregnancy for herself, but she defied the odds to give birth to daughter Sunday Rose in 2008.

When it came time to for her fourth child, however, she turned to a surrogate. She and Urban welcomed daughter in Faith Margaret in 2010, and the couple may not be done having children just yet. Kidman apparently told reporters that she'd welcome another baby, and noted that her grandmother gave birth at 49— the same age she is now.

9 Lucy Liu

Lucy Liu's decision to use a surrogate came as a shock to some. The Elementary actress was 46 when she welcomed a son, but didn't reveal any fertility struggles when she announced her new addition. A physical inability to get pregnant or carry a pregnancy to term, however, is not necessarily a prerequisite for using a surrogate.

Though infertility may or may not have played a role in Liu's choice, she told People magazine of her surrogacy that, “It just seemed like the right option for me because I was working and I didn’t know when I was going to be able to stop." Liu also chose to go it alone and raise baby Rockwell as a single mother. In another interview, Liu said that was totally shocked by those who criticized her decision.

8 Angela Bassett

It took seven years of heartbreak for Hollywood couple Angela Bassett and Courtney B. Vance to become parents. And it might not have ever happened at all were it not for a chance conversation with a friend who used a surrogate. Appearing on Oprah a few years ago, the actress and actor said they'd endured failure after failure in their quest to have a baby, including attempts at IVF.

But they spoke with a friend one day who announced she was expecting a baby— which led to some confusion because they could see she clearly was not pregnant herself. They learned she was using a surrogate, and Bassett and Vance started looking into the idea for themselves. They decided to give it a try and in 2006, the couple welcomed boy/girl twins Bronwyn and Slater.

7 Marissa Jaret Winokur

Hairspray star Marisa Jaret Winokur endured the fight of her life before her fight to have a baby began. Winokur survived a battle with cervical cancer at just 27 years old, but sadly she lost her cervix and part of her uterus. That meant there was no possibility of getting pregnant herself, so the only option available to her to have a biological child would be to find a surrogate.

She and husband Judah Miller ultimately decided to give it a shot, and Winokur said she became very close to the surrogate— she attended prenatal appointments and was by her side for the birth. Winokur and Miller welcomed son Zev Isaac in 2008. Winokur said she gained a life-long friend in her surrogate in addition to her miracle baby.

6 Giuliana Rancic

Reality TV star Giuliana Rancic has been an open book when it comes to her battle with infertility. She underwent a double mastectomy and beat breast cancer, but has had to continue taking cancer fighting drugs for years. That means it would be both difficult and dangerous for her to get pregnant herself. With that in mind, she and husband Bill Rancic turned to a surrogate to have their son Duke in 2012.

The couple had hoped their surrogate would be able to help expand their family, and had three frozen embryos ready to go. Sadly, the surrogate suffered a miscarriage with twins the first time and lost the next pregnancy as well. There's still some hope for the Rancics to add to their family, however. Giuliana has said they are open to the idea of adoption.

5 Camille Grammer

Real Housewives of Beverly Hills star Camille Grammer has been accused by some of using a surrogate to carry her children for superficial reasons— namely, that she didn't want to lose her figure. In a blog post for her show, however, Grammer seemed to acknowledge trying and failing to get pregnant, saying: "If you can’t get pregnant for whatever reason, it’s great to know that there are options available for people that want to have a family. I wish I could have had that experience."

Instead, she and actor ex-husband Kelsey Grammer turned to a surrogate to give birth to daughter Mason in 2001 and son Jude in 2004. While neither have ever addressed their reasons for choosing surrogacy, there's also been some speculation the Camille's Irritable Bowel Syndrome may have made it more difficult for her to get pregnant.

4 Katey Segal

Married with Children actress Katy Sagal had already had two children by the time she met and married husband Kurt Sutter. She delivered both children herself, but said that the births of her son and daughter left her with some medical issues that made conceiving another child very difficult. She and Sutter were completely open to the idea of adoption, and said they would have been happy to bring home a child in any way they could.

But their plans for a surrogate worked out first, and at 52 years old Sagal welcomed daughter Esmé Louise. While it was her third child, it was Sutter's first. The couple became close with the surrogate over the course of the pregnancy, attending medical appointments and being at her side for the birth.

3 Joan Lunden

Former Good Morning America co-host Joan Lunden turned to surrogacy not once, but twice. After having three children with her first husband she went through a bitter divorce. When she remarried, she and her second husband decided to have children together but struggled to do so. They turned to a surrogate, who helped them welcome boy/girl twins.

Lunden gushed about the experience and about the woman who made it possible. They grew close so close throughout the pregnancy, in fact, that Lunden and her husband asked the same woman to carry another pregnancy for them a few years later. Once again, they came home with boy/girl twins. Lunden has said she makes sure all 4 children send their surrogate a card on Mother's Day ever year, because their family owes her so much.

2 Taylor Dane

Singer Taylor Dayne may be known for her romantic love songs, but she found herself single and ready to be a mother in the early 2000's. She was in her early 40's and worried that her time to become a mom was running out. With no relationship prospects on the table, she first started to looking into adopting on her own. But when someone mentioned surrogacy to her, she was intrigued by the option she cheekily referred to as "renting a womb."

At the time, using a surrogate was illegal in her home state of New York, so Dayne was forced to fly back and forth across the country to her surrogate in California. The payoff was a double blessing, however. Dayne's surrogate gave birth to boy/girl twins Astaria and Levi.

1 Michelle Stafford

Former The Young and The Restless star Michelle Stafford wanted to be a mom for years before she finally made it happen. Stafford first looked into adoption, but said she ran into too many roadblocks and too much red tape as a single mother. She also underwent three IVF treatments, but none of them were successful. She finally decided to turn to a surrogate, and welcomed a baby girl named Natalia Scout Lee in December of 2009.

Despite the challenges and struggles of raising a baby on her own, she loved motherhood so much that she decided to expand her family. Knowing she had more frozen embryos on hand, she used a surrogate once again to give Natalia a little brother. Jamison Jones Lee was born in October of 2015.

Sources: People, US Weekly, Daily Mail, Allthingsrh.com