Sarah Jessica Parker, Jimmy Fallon, and Michael Jackson don’t necessarily seem like they have much in common at first blush, but these three celebrities do share one important quality: all of them became parents through surrogacy. Although knowledge of surrogacy as a family-building option is increasing due to high-profile celebrity parents (Kim Kardashian West has reportedly hired a surrogate to carry her third child), the ins and outs of the surrogacy process are still pretty mysterious to most people. How do you find a surrogate? How much does it cost? How does it work?

When people discuss surrogacy, they’re most commonly referring to gestational surrogacy, where someone carries a fetus that is genetically related to the intended parents (or parent). There is also egg donation surrogacy, where a surrogate will carry a fetus from a donated egg, as well as traditional surrogacy, where the surrogate uses her own eggs. As a form of assisted reproduction, surrogacy is still fairly rare. Although there’s no reliable statistics, the use of surrogates is going up, with numbers estimating about 1,500 babies being born in the US via surrogacy in 2011, up from about 700 in 2004.

Emily Sonier, LICSW, a licensed social worker and clinical director at Circle Surrogacy in Boston, explains that oftentimes people choosing surrogacy have exhausted all other options before deciding to pursue a child via a surrogate. Older parents, single parents, or people with medical conditions that prohibit pregnancy often consider surrogates, too.

How do the logistics around surrogacy work?
Many prospective parents choose to work with a surrogacy agency who handles details for both the intended parents and the surrogates. Agencies take applications, screen candidates, perform background checks, and match intended parents with surrogates. At Circle, where Sonier works, there is an entire team assigned to each case, including a coordinator, a social worker, attorney, and even a person who handles the finances. Some surrogacy agencies are local, so they connect parents and surrogates in a certain geographical area. Others, like Circle or Family Source Consultants out of Chicago, work with surrogates and intended parents around the country and the world.

Once a match is made, a contract that stipulates all aspects of the process and agreement is drawn up, agreed upon by the parties, and reviewed by a lawyer. Contracts will cover everything from compensation to the amount of contact between the surrogate and family after birth, and more.

As a rule, surrogacy is expensive. Although insurance may cover some aspects and financing can be available through agencies, the average cost ranges anywhere from $30,000 up to $100,000 or more, depending on the situation — if egg donation is included, for example, whether it is private or through an agency, and the location of the parents and surrogate (international surrogacy is often much more costly). Fees generally include legal services, agency services, medical care, and travel for the surrogate, as well as items like maternity clothes, lost wages, and more.

Independent surrogacy, where people make a private agreement (aka not through an agency or other third party) is also on the rise. Susan Taylor, LM, CPM, a home birth midwife in Texas and a two-time surrogate, used an independent agreement during her first surrogacy experience. She explains: “Erin, my former intended mom, and I talked on the phone for hours before deciding to meet for dinner with our husbands. After that, it was official. We were matched!” These types of agreements usually still include a contract and input from a lawyer. Interestingly, laws around surrogacy differ from state to state and country to country. In five US states (including Michigan) surrogacy contracts are unenforceable, according to a 2014 article in the New York Times.

How does it work for the surrogate?
Most surrogates are people who have been pregnant before and feel a call to help others. For Taylor, it was a desire to birth again, even though she and her husband felt their family was complete: “Our youngest, Finn, was the missing piece I had longed for. My husband and I talked a lot about [another child], but we both felt like we were done having babies of our own. However, I couldn’t seem to reconcile the way I was feeling. One night I was watching a reality show that followed a TV host who was recently diagnosed with cancer after many IVF attempts. She and her husband ultimately decided on surrogacy. Instantly, my heart skipped a beat and I knew that was it! “

Surrogates usually go through IVF (and many many hormone shots and tests, says Taylor) to get pregnant. Once pregnant, they work with their own medical teams to manage their pregnancies. They receive payments from the intended parents or agency as stipulated in their contract, usually in installments.

What happens during the pregnancy, birth, and afterwards?
Intended parents and surrogates keep in touch throughout the IVF process and the pregnancy. Sonier explains that clients at her agency are required to be in contact often: “We want intended parents and surrogates to communicate a lot. They’ve usually met at least three times before the baby is born. We hope that they’re building trust with each other.”

Depending on where they live in relation to the surrogate, intended parents can attend medical appointments, ultrasounds, and, often, the birth of their child. Sometimes, a further agreement past birth will be in place, like the opportunity for the surrogate to pump breastmilk and send it to the baby. Agencies will usually follow up with both parties to ensure everything is going well after birth, including postpartum mental health checks for the surrogate.

And most often, the relationship between the surrogate and the intended parents continues in some form. Taylor’s second surrogacy experience was with a gay male couple who lives in Spain, people she now considers “lifelong friends.” Although they couldn’t attend medical appointments due to distance, they arrived shortly after the birth of their baby, in time to cut the cord. Taylor and her family are even planning a trip to Spain next summer.

Although it’s often complicated (medically, legally, financially and emotionally) for parents and surrogates alike, the surrogacy experience can be positive and life-changing. Taylor says her two experiences as a surrogate were incredible: “The best thing is the moment you see your intended parents hold their baby for the first time. Hands down. It makes the entire process worth it. It makes you want to do it over and over again. It’s an indescribable feeling.”

Carrie Murphy is a freelance writer and doula in Albuquerque, NM. Read more on her website, carrie-murphy.com.