Birth tourism has been in the news in the last several years and is often a controversial subject debated by national leaders and those working for them, but many people don't know much about the practice or how it works. Whenever a woman travels to another country in order to give birth in that country, she is usually considered a birth tourist. Women travel to the U.S. and many other countries every year in order to get pregnancy-related care and to give birth, and the reasons they cite are not always what critics of the practice think.

At the heart of the practice is the fact that there are benefits and drawbacks for those who are born there. Around the globe, there are over 190 recognized countries, each with its own set of customs and laws that govern the rights and privileges of citizenship. Countries often have differing or even conflicting policies that people may agree with or reject. Parents often consider birth tourism in light of what opportunities they can give to their newborn, and different countries confer different rights on those born within its borders. Other parents consider costs and quality of care, and because there are so many reasons, it is a difficult subject to pin down.

As birth tourism continues to be a sensitive button issue in both local and global sects, many are finding out just how complex and hidden the world of birth tourism is. Here are 25 Surprising Facts About Birth Tourism.

25 Automatic Citizenship Not Guaranteed

Birth tourism occurs in many forms. Most experts also consider the short trip across the Mexico-U.S. border by pregnant mothers to be a form of birth tourism, but the babies born to these mothers may not be granted automatic citizenship.

Some people are now having their U.S.-issued birth certificates called into question by the current administration for citizenship fraud, according to the Washington Post.

Canada—citing international law and policies in place in the majority of countries—is having a similar debate concerning automatic citizenship, reports The Star.

24 Some Ask Parents To Choose

Many parents jet-set around the globe for work or other reasons, and often Mom and Dad are not even the same nationality. Some countries will ask parents to choose what citizenship should apply to their child, as per Global Times.

The key is often the passport, which can open up lifelong educational and business opportunities to the holder.

The law of some countries, however, doesn't allow for dual citizenship and requires parents to choose in which country their baby will become a citizen.

23 Mom May Not Have To Get To The Mainland

A lot of people don't realize that a pregnant mother doesn't have to travel to the mainland U.S. in order to get U.S. citizenship for her baby. There are a number of U.S. territories in the Pacific Ocean—including the island of Saipan in the Northern Marianas chain—where women from other countries can travel to give birth, explains the Wall Street Journal. The laws regarding visas are different for Saipan and allow people to go there without a visa for up to 45 days.

22 It's Big Business

So long as women don't lie about why they're coming, birth tourism is legal in the U.S., and many companies are springing up to take advantage of the business side of things.

Birth tourism can generate thousands of dollars in revenue from just a single birth, according to NBC News.

Often, the women coming purchase luxury packages online that include room, laundry and meal service and hospital fees. In Los Angeles, much of the birth tourism is generated from China, while Miami has become a hot destination for mothers from Russia.

21 Asia Sends The Most Moms

Despite the fact that birth tourism isn't illegal in the U.S., much of the business is hidden and the powers that be don't seem to know a lot of statistics about who is actually coming to the U.S. to give birth.

Many people might be surprised to find that Asian countries like China and Korea likely send the most mothers, according to the Center For Immigration Studies.

Other countries that have a growing birth tourism industry sending mothers to give birth in the U.S. are Turkey, Nigeria and Russia.

20 some do it For Tax Purposes

Birth tourism into the U.S. is probably not for tax reasons, as the U.S. and Eritrea are the only two countries in the world that tax its citizens no matter where they're living, as per Nomad Capitalist.

Acquiring dual citizenship means that once that child becomes an adult, they may have to pay taxes in both countries, according to Investopedia.

Some countries have treaties that override that rule, but others don't. Some countries don't allow dual citizenship; so, the parents might choose whichever country assesses fewer taxes.

19 Right Of Abode

Even though Hong Kong reverted back to Chinese control in 1997, it continues to be administrated differently than mainland China and is considered to be a freer society.

Sometimes, the goal of birth tourism isn't to acquire another citizenship for the baby but to establish the right of abode, which is the ability to live in a place without special documents or restrictions, such as length of time, according to Community Legal Information Centre.

Right of abode can be complicated and has gotten more difficult to obtain recently.

18 The Cost Of Giving Birth

The cost of giving birth varies wildly from country to country. Hospital costs in the U.S. have been soaring, while just across its borders, both Canada and Mexico often provide similar top-quality care for a fraction of the price, reveals Insider.

The price of birth-care is a big motivator for new mothers to move to Western countries to give birth.

While many countries like Brazil and Argentina can provide even C-sections for under $3,000, countries like Japan will set a mom back over $60,000—but it also provides extra amenities and has the lowest rate of infant mortality in the world. Compare that to Spain, which charges under $2,000 for most births.

17 A Matter Of Procedure

Lumped under the birth tourism umbrella is pregnancy tourism, which involves people traveling for pregnancy and birth-related procedures, like in-vitro fertilization (IVF) treatment.

Many U.S. citizens are making the trip to countries like India for these costly procedures, despite the lack of laws surrounding surrogacy there, as per Asia Sentinel.

Often, the lure of a far cheaper price tag brings tourists from around the globe to a country that may allow a procedure that isn't available everywhere. C-sections often vary in cost from country to country, as per Insider.

In the U.S., it is completely legal to travel to the states as a tourist who just happens to give birth while she's here, according to KCET. The only time that the legality of a foreign national giving birth in the U.S. is questioned is when there have been demonstrable indications of the attempt to commit fraud—and that's a blurry line.

If the mother has been completely honest about their intentions, the process is legal.

Many argue that these women are tourists just like anyone else and that the citizenship their baby earns at birth isn't a violation of their visa.

15 Not An Anchor Baby

'Anchor baby' is a reference to the idea that when undocumented immigrants have a baby on U.S. soil, it will be harder for U.S. officials to deport the parents, explains the Washington Post.

There is no indication that this is the case; thousands of parents are deported every year.

Most of the babies born as a result of birth tourism do not appear to remain in the U.S.; they are usually taken back with parents to their home country.

14 Who Offers 'Right Of Soil'

Right of soil—or jus soli in Latin—is the concept that a person belongs to the land or country in which they are born.

People might be surprised to learn that only 30 countries adhere to the rule of jus soli, and the majority of those countries are in North, Central and South America, according to World Atlas.

Several countries are reevaluating their practice of jus soli, including Canada and the U.S., in part because of a conflation of birth tourism with illegal immigration.

13 It's Not A Last-Minute Dash

The vast majority of births in the U.S. to foreign-born parents are not a last-minute decision, especially considering that most airlines won't allow a pregnant woman to fly in the last few weeks before birth. Also, birth tourism is often expensive—women often arrive in their fourth or fifth month of pregnancy and pay thousands of dollars a month just for their care leading up to the birth, and then they pay hospital fees, as per Vox. Many women who come are well-off, but not all—some have saved for years in order to afford the trip.

12 Insurance Policy Conundrums

Often, the end goal in birth tourism is obtaining a passport for the globe-trotting baby. A passport can mean different things in different countries, with some passports allowing for greater ease of access.

A number of countries offer passports that let the holder visit specific countries or areas without having to obtain a visa—an uncertain and complicated process at best in many places, according to Nomad Capitalist.

Some mothers even consider the U.S. passport valuable enough that they're willing to risk tax issues when their child is grown.

11 Birth Hotels Galore

It's difficult to know how many there are just in the U.S., but birth hotels are often hidden in plain sight in residential communities. Some might be a large, single family home that is divided up to house multiple women with caregivers, while others are actually small hotels that have been taken over by a business specializing in selling birth tourism packages, as per Rolling Stone.

There are special places for families and their children while going through the process.

These hotels often have in-house staff who provide daily meals, laundry service and a nursery.

10 Policies At Home

Even though China's One Child policy technically ended in 2015, many Chinese women still travel to other countries to give birth, according to the Los Angeles Times.

Traveling to the United States to give birth was often seen as a way to circumvent the nation's enforced family planning policy.

Women continue to look towards the U.S.—despite its tax laws—because they're thinking of the educational opportunities that their child could take advantage of. Single mothers in China also face discrimination and bureaucracy.

9 No One Knows How Many

The biggest issue with the birth tourism industry is that no one knows how many women are traveling for the sole purpose of giving birth.

While not illegal, it remains controversial in many countries.

For this reason, there are no solid numbers. One study indicated that approximately 40,000 babies are born to women visiting the U.S. on a travel visa, according to the New York Post. The conservative Center For Immigration Studies estimated that number to be 36,000. Another source indicated that around 20,000 Chinese women traveled to give birth, as per Data Bits.

8 The 14th Amendment Connection

Birth tourism is legal at this point because of its fundamental ties to the 14th amendment, which corrected an earlier supreme court ruling and provides citizenship to everyone born or naturalized in the U.S., according to NPR. Originally designed to accord the same rights of citizenship to people of color who hail from the states, the amendment was further defined in 1898 to incorporate the legal concept of jus soli, or 'right of soil.' This is different than the more common global philosophy that links citizenship to ancestry.

7 The Best Medical Care

While many people assume that the primary draw in birth tourism is obtaining citizenship, often parents—especially those from Eastern Europe—cite the desire for better medical care and more choices when asked why they traveled to the US, as per Fox News 13.

Despite policymakers' concerns, the majority of parents who come to the U.S. obtain no insurance and pay all their bills in cash, and then after a short period of time return home—with a tiny U.S. citizen in tow.

6 What The Passport Means

Not all passports are created equal; some offer more freedom than others. Parents who travel a lot—or who wish to give their child a wide range of options—often participate in birth tourism to some unexpected places, such as St. Kitts and Nevis, Panama and Uruguay.

These and several other countries permit travel visa-free to Central and South America and to countries in the Schengen Area.

The Schengen Area is a 26-country bloc that doesn't have border checks with the right documentation, according to the European Commission.