NEW YORK, May 11 (Thomson Reuters Foundation) - The governor of New Jersey declined to sign a measure into law on Thursday that would have made the U.S. state the first to ban child marriage without exception.

Republican Chris Christie, a supporter of President Donald Trump, said such a ban would conflict with religious customs.

Underage marriage is widespread in the United States, where about 170,000 children were wed between 2000 and 2010 in 38 of the 50 states where data was available, according to activists.

Although age 18 is the minimum for marriage in most of the nation, every state has legal loopholes allowing children to wed.

The New Jersey bill would have prohibited any marriage of children under age 18.

Christie conditionally vetoed the measure, sending it back to the state legislature with proposed changes. He said it should have an exception so a judge can approve marriages for 16- and 17-year-olds.

20 PHOTOS NTP: Bangladesh youth marriages See Gallery NTP: Bangladesh youth marriages MANIKGANJ, BANGLADESH - AUGUST 20: 15 year old Nasoin Akhter has her makeup done at a beauty parlour on the day of her wedding to a 32 year old man, August 20, 2015 in Manikganj, Bangladesh. In June of this year, Human Rights Watch released a damning report about child marriage in Bangladesh. The country has one of the highest rates of child marriage in the world, with 29% of girls marrying before the age of 15, and 65% of girls marrying before they turn 18. The detrimental effects of early marriage on a girl cannot be overstated. Most young brides drop out of school. Pregnant girls from 15-20 are twice as likely to die in childbirth than those 20 or older, while girls under 15 are at five times the risk. Research cites spousal age difference as a significant risk factor for violence and sexual abuse. Child marriage is attributed to both cultural tradition and poverty. Parents believe that it 'protects' girls from sexual assault and harassment. Larger dowries are not required for young girls, and economically, women's earnings are insignificant as compared to men's. (Photo by Allison Joyce/Getty Images) MANIKGANJ, BANGLADESH - AUGUST 20: 32 year old Mohammad Hasamur Rahman stands on a bed above his new bride, 15 year old Nasoin Akhter, August 20, 2015 in Manikganj, Bangladesh. In June of this year, Human Rights Watch released a damning report about child marriage in Bangladesh. The country has one of the highest rates of child marriage in the world, with 29% of girls marrying before the age of 15, and 65% of girls marrying before they turn 18. The detrimental effects of early marriage on a girl cannot be overstated. Most young brides drop out of school. Pregnant girls from 15-20 are twice as likely to die in childbirth than those 20 or older, while girls under 15 are at five times the risk. Research cites spousal age difference as a significant risk factor for violence and sexual abuse. Child marriage is attributed to both cultural tradition and poverty. Parents believe that it 'protects' girls from sexual assault and harassment. Larger dowries are not required for young girls, and economically, women's earnings are insignificant as compared to men's. (Photo by Allison Joyce/Getty Images) MANIKGANJ, BANGLADESH - AUGUST 20: A relative tries to drag 15 year old Nasoin Akhter onto a bed to pose for photographs on the day of her wedding to a 32 year old man, August 20, 2015 in Manikganj, Bangladesh. In June of this year, Human Rights Watch released a damning report about child marriage in Bangladesh. The country has one of the highest rates of child marriage in the world, with 29% of girls marrying before the age of 15, and 65% of girls marrying before they turn 18. The detrimental effects of early marriage on a girl cannot be overstated. Most young brides drop out of school. Pregnant girls from 15-20 are twice as likely to die in childbirth than those 20 or older, while girls under 15 are at five times the risk. Research cites spousal age difference as a significant risk factor for violence and sexual abuse. Child marriage is attributed to both cultural tradition and poverty. Parents believe that it 'protects' girls from sexual assault and harassment. Larger dowries are not required for young girls, and economically, women's earnings are insignificant as compared to men's. (Photo by Allison Joyce/Getty Images) MANIKGANJ, BANGLADESH - AUGUST 20: 15 year old Nasoin Akhter has her wedding sari wrapped at a beauty parlour on the day of her wedding to a 32 year old man, August 20, 2015 in Manikganj, Bangladesh. In June of this year, Human Rights Watch released a damning report about child marriage in Bangladesh. The country has one of the highest rates of child marriage in the world, with 29% of girls marrying before the age of 15, and 65% of girls marrying before they turn 18. The detrimental effects of early marriage on a girl cannot be overstated. Most young brides drop out of school. Pregnant girls from 15-20 are twice as likely to die in childbirth than those 20 or older, while girls under 15 are at five times the risk. Research cites spousal age difference as a significant risk factor for violence and sexual abuse. Child marriage is attributed to both cultural tradition and poverty. Parents believe that it 'protects' girls from sexual assault and harassment. Larger dowries are not required for young girls, and economically, women's earnings are insignificant as compared to men's. (Photo by Allison Joyce/Getty Images) MANIKGANJ, BANGLADESH - AUGUST 20: Wedding guests dance and celebrate on the day of the wedding of 15 year old Nasoin Akhter to a 32 year old man, August 20, 2015 in Manikganj, Bangladesh. In June of this year, Human Rights Watch released a damning report about child marriage in Bangladesh. The country has one of the highest rates of child marriage in the world, with 29% of girls marrying before the age of 15, and 65% of girls marrying before they turn 18. The detrimental effects of early marriage on a girl cannot be overstated. Most young brides drop out of school. Pregnant girls from 15-20 are twice as likely to die in childbirth than those 20 or older, while girls under 15 are at five times the risk. Research cites spousal age difference as a significant risk factor for violence and sexual abuse. Child marriage is attributed to both cultural tradition and poverty. Parents believe that it 'protects' girls from sexual assault and harassment. Larger dowries are not required for young girls, and economically, women's earnings are insignificant as compared to men's. (Photo by Allison Joyce/Getty Images) MANIKGANJ, BANGLADESH - AUGUST 20: 15 year old Nasoin Akhter is bathed on the day of her wedding to a 32 year old man, August 20, 2015 in Manikganj, Bangladesh. In June of this year, Human Rights Watch released a damning report about child marriage in Bangladesh. The country has one of the highest rates of child marriage in the world, with 29% of girls marrying before the age of 15, and 65% of girls marrying before they turn 18. The detrimental effects of early marriage on a girl cannot be overstated. Most young brides drop out of school. Pregnant girls from 15-20 are twice as likely to die in childbirth than those 20 or older, while girls under 15 are at five times the risk. Research cites spousal age difference as a significant risk factor for violence and sexual abuse. Child marriage is attributed to both cultural tradition and poverty. Parents believe that it 'protects' girls from sexual assault and harassment. Larger dowries are not required for young girls, and economically, women's earnings are insignificant as compared to men's. (Photo by Allison Joyce/Getty Images) MANIKGANJ, BANGLADESH - AUGUST 20: 15 year old Nasoin Akhter is bathed on the day of her wedding to a 32 year old man, August 20, 2015 in Manikganj, Bangladesh. In June of this year, Human Rights Watch released a damning report about child marriage in Bangladesh. The country has one of the highest rates of child marriage in the world, with 29% of girls marrying before the age of 15, and 65% of girls marrying before they turn 18. The detrimental effects of early marriage on a girl cannot be overstated. Most young brides drop out of school. Pregnant girls from 15-20 are twice as likely to die in childbirth than those 20 or older, while girls under 15 are at five times the risk. Research cites spousal age difference as a significant risk factor for violence and sexual abuse. Child marriage is attributed to both cultural tradition and poverty. Parents believe that it 'protects' girls from sexual assault and harassment. Larger dowries are not required for young girls, and economically, women's earnings are insignificant as compared to men's. (Photo by Allison Joyce/Getty Images) MANIKGANJ, BANGLADESH - AUGUST 20: 15 year old Nasoin Akhter is bathed on the day of her wedding to a 32 year old man, August 20, 2015 in Manikganj, Bangladesh. In June of this year, Human Rights Watch released a damning report about child marriage in Bangladesh. The country has one of the highest rates of child marriage in the world, with 29% of girls marrying before the age of 15, and 65% of girls marrying before they turn 18. The detrimental effects of early marriage on a girl cannot be overstated. Most young brides drop out of school. Pregnant girls from 15-20 are twice as likely to die in childbirth than those 20 or older, while girls under 15 are at five times the risk. Research cites spousal age difference as a significant risk factor for violence and sexual abuse. Child marriage is attributed to both cultural tradition and poverty. Parents believe that it 'protects' girls from sexual assault and harassment. Larger dowries are not required for young girls, and economically, women's earnings are insignificant as compared to men's. (Photo by Allison Joyce/Getty Images) MANIKGANJ, BANGLADESH - AUGUST 20: Gold wedding jewelry is laid out for 15 year old Nasoin Akhter on the day of her wedding to a 32 year old man, August 20, 2015 in Manikganj, Bangladesh. In June of this year, Human Rights Watch released a damning report about child marriage in Bangladesh. The country has one of the highest rates of child marriage in the world, with 29% of girls marrying before the age of 15, and 65% of girls marrying before they turn 18. The detrimental effects of early marriage on a girl cannot be overstated. Most young brides drop out of school. Pregnant girls from 15-20 are twice as likely to die in childbirth than those 20 or older, while girls under 15 are at five times the risk. Research cites spousal age difference as a significant risk factor for violence and sexual abuse. Child marriage is attributed to both cultural tradition and poverty. Parents believe that it 'protects' girls from sexual assault and harassment. Larger dowries are not required for young girls, and economically, women's earnings are insignificant as compared to men's. (Photo by Allison Joyce/Getty Images) MANIKGANJ, BANGLADESH - AUGUST 20: 32 year old Mohammad Hasamur Rahman arrives to his wedding venue on the day that he will marry 15 year old Nasoin Akhter August 20, 2015 in Manikganj, Bangladesh. In June of this year, Human Rights Watch released a damning report about child marriage in Bangladesh. The country has one of the highest rates of child marriage in the world, with 29% of girls marrying before the age of 15, and 65% of girls marrying before they turn 18. The detrimental effects of early marriage on a girl cannot be overstated. Most young brides drop out of school. Pregnant girls from 15-20 are twice as likely to die in childbirth than those 20 or older, while girls under 15 are at five times the risk. Research cites spousal age difference as a significant risk factor for violence and sexual abuse. Child marriage is attributed to both cultural tradition and poverty. Parents believe that it 'protects' girls from sexual assault and harassment. Larger dowries are not required for young girls, and economically, women's earnings are insignificant as compared to men's. (Photo by Allison Joyce/Getty Images) MANIKGANJ, BANGLADESH - AUGUST 20: 15 year old Nasoin Akhter sits with relatives while posing for photos on the day of her wedding to a 32 year old man, August 20, 2015 in Manikganj, Bangladesh. In June of this year, Human Rights Watch released a damning report about child marriage in Bangladesh. The country has one of the highest rates of child marriage in the world, with 29% of girls marrying before the age of 15, and 65% of girls marrying before they turn 18. The detrimental effects of early marriage on a girl cannot be overstated. Most young brides drop out of school. Pregnant girls from 15-20 are twice as likely to die in childbirth than those 20 or older, while girls under 15 are at five times the risk. Research cites spousal age difference as a significant risk factor for violence and sexual abuse. Child marriage is attributed to both cultural tradition and poverty. Parents believe that it 'protects' girls from sexual assault and harassment. Larger dowries are not required for young girls, and economically, women's earnings are insignificant as compared to men's. (Photo by Allison Joyce/Getty Images) MANIKGANJ, BANGLADESH - AUGUST 20: 15 year old Nasoin Akhter poses for a photo at a beauty parlour on the day of her wedding to a 32 year old man, August 20, 2015 in Manikganj, Bangladesh. In June of this year, Human Rights Watch released a damning report about child marriage in Bangladesh. The country has one of the highest rates of child marriage in the world, with 29% of girls marrying before the age of 15, and 65% of girls marrying before they turn 18. The detrimental effects of early marriage on a girl cannot be overstated. Most young brides drop out of school. Pregnant girls from 15-20 are twice as likely to die in childbirth than those 20 or older, while girls under 15 are at five times the risk. Research cites spousal age difference as a significant risk factor for violence and sexual abuse. Child marriage is attributed to both cultural tradition and poverty. Parents believe that it 'protects' girls from sexual assault and harassment. Larger dowries are not required for young girls, and economically, women's earnings are insignificant as compared to men's. (Photo by Allison Joyce/Getty Images) MANIKGANJ, BANGLADESH - AUGUST 20: 15 year old Nasoin Akhter stands in the doorway of a neighbors home on the day of her wedding to a 32 year old man, August 20, 2015 in Manikganj, Bangladesh. In June of this year, Human Rights Watch released a damning report about child marriage in Bangladesh. The country has one of the highest rates of child marriage in the world, with 29% of girls marrying before the age of 15, and 65% of girls marrying before they turn 18. The detrimental effects of early marriage on a girl cannot be overstated. Most young brides drop out of school. Pregnant girls from 15-20 are twice as likely to die in childbirth than those 20 or older, while girls under 15 are at five times the risk. Research cites spousal age difference as a significant risk factor for violence and sexual abuse. Child marriage is attributed to both cultural tradition and poverty. Parents believe that it 'protects' girls from sexual assault and harassment. Larger dowries are not required for young girls, and economically, women's earnings are insignificant as compared to men's. (Photo by Allison Joyce/Getty Images) MANIKGANJ, BANGLADESH - AUGUST 20: 15 year old Nasoin Akhter looks out of a dressing room at a beauty parlour on the day of her wedding to a 32 year old man, August 20, 2015 in Manikganj, Bangladesh. In June of this year, Human Rights Watch released a damning report about child marriage in Bangladesh. The country has one of the highest rates of child marriage in the world, with 29% of girls marrying before the age of 15, and 65% of girls marrying before they turn 18. The detrimental effects of early marriage on a girl cannot be overstated. Most young brides drop out of school. Pregnant girls from 15-20 are twice as likely to die in childbirth than those 20 or older, while girls under 15 are at five times the risk. Research cites spousal age difference as a significant risk factor for violence and sexual abuse. Child marriage is attributed to both cultural tradition and poverty. Parents believe that it 'protects' girls from sexual assault and harassment. Larger dowries are not required for young girls, and economically, women's earnings are insignificant as compared to men's. (Photo by Allison Joyce/Getty Images) MANIKGANJ, BANGLADESH - AUGUST 20: 32 year old Mohammad Hasamur Rahman poses for photographs with his new bride, 15 year old Nasoin Akhter, August 20, 2015 in Manikganj, Bangladesh. In June of this year, Human Rights Watch released a damning report about child marriage in Bangladesh. The country has one of the highest rates of child marriage in the world, with 29% of girls marrying before the age of 15, and 65% of girls marrying before they turn 18. The detrimental effects of early marriage on a girl cannot be overstated. Most young brides drop out of school. Pregnant girls from 15-20 are twice as likely to die in childbirth than those 20 or older, while girls under 15 are at five times the risk. Research cites spousal age difference as a significant risk factor for violence and sexual abuse. Child marriage is attributed to both cultural tradition and poverty. Parents believe that it 'protects' girls from sexual assault and harassment. Larger dowries are not required for young girls, and economically, women's earnings are insignificant as compared to men's. (Photo by Allison Joyce/Getty Images) MANIKGANJ, BANGLADESH - AUGUST 19: 14 year old Mousammat Akhi Akhter poses in her home August 19, 2015 in Manikganj, Bangladesh. Last year, when she was only 13, Akhi got married a 27 year old man. She had finished 6th grade and wanted to wait until she was older to get married, but she says her parents felt social pressure to marry her young. In June of this year, Human Rights Watch released a damning report about child marriage in Bangladesh. The country has one of the highest rates of child marriage in the world, with 29% of girls marrying before the age of 15, and 65% of girls marrying before they turn 18. The detrimental effects of early marriage on a girl cannot be overstated. Most young brides drop out of school. Pregnant girls from 15-20 are twice as likely to die in childbirth than those 20 or older, while girls under 15 are at five times the risk. Research cites spousal age difference as a significant risk factor for violence and sexual abuse. Child marriage is attributed to both cultural tradition and poverty. Parents believe that it 'protects' girls from sexual assault and harassment. Larger dowries are not required for young girls, and economically, women's earnings are insignificant as compared to men's. (Photo by Allison Joyce/Getty Images) MANIKGANJ, BANGLADESH - AUGUST 19: 27 year old Mohammad Sujon Mia stands for a photo beside his wife, 14 year old Mousammat Akhi Akhter in their home August 19, 2015 in Manikganj, Bangladesh. Last year, when she was only 13, Akhi got married a 27 year old man. She had finished 6th grade and wanted to wait until she was older to get married, but she says her parents felt social pressure to marry her young. In June of this year, Human Rights Watch released a damning report about child marriage in Bangladesh. The country has one of the highest rates of child marriage in the world, with 29% of girls marrying before the age of 15, and 65% of girls marrying before they turn 18. The detrimental effects of early marriage on a girl cannot be overstated. Most young brides drop out of school. Pregnant girls from 15-20 are twice as likely to die in childbirth than those 20 or older, while girls under 15 are at five times the risk. Research cites spousal age difference as a significant risk factor for violence and sexual abuse. Child marriage is attributed to both cultural tradition and poverty. Parents believe that it 'protects' girls from sexual assault and harassment. Larger dowries are not required for young girls, and economically, women's earnings are insignificant as compared to men's. (Photo by Allison Joyce/Getty Images) MANIKGANJ, BANGLADESH - AUGUST 20: 15 year old Nasoin Akhter is led by relatives to a car that will take her to her new home on the day of her wedding to a 32 year old man, August 20, 2015 in Manikganj, Bangladesh. In June of this year, Human Rights Watch released a damning report about child marriage in Bangladesh. The country has one of the highest rates of child marriage in the world, with 29% of girls marrying before the age of 15, and 65% of girls marrying before they turn 18. The detrimental effects of early marriage on a girl cannot be overstated. Most young brides drop out of school. Pregnant girls from 15-20 are twice as likely to die in childbirth than those 20 or older, while girls under 15 are at five times the risk. Research cites spousal age difference as a significant risk factor for violence and sexual abuse. Child marriage is attributed to both cultural tradition and poverty. Parents believe that it 'protects' girls from sexual assault and harassment. Larger dowries are not required for young girls, and economically, women's earnings are insignificant as compared to men's. (Photo by Allison Joyce/Getty Images) MANIKGANJ, BANGLADESH - AUGUST 19: 14 year old Shima Akhter stands on the front porch of her home August 19, 2015 in Manikganj, Bangladesh. Last year, when she was 13, Shima married an 18 year old man. In June of this year, Human Rights Watch released a damning report about child marriage in Bangladesh. The country has one of the highest rates of child marriage in the world, with 29% of girls marrying before the age of 15, and 65% of girls marrying before they turn 18. The detrimental effects of early marriage on a girl cannot be overstated. Most young brides drop out of school. Pregnant girls from 15-20 are twice as likely to die in childbirth than those 20 or older, while girls under 15 are at five times the risk. Research cites spousal age difference as a significant risk factor for violence and sexual abuse. Child marriage is attributed to both cultural tradition and poverty. Parents believe that it 'protects' girls from sexual assault and harassment. Larger dowries are not required for young girls, and economically, women's earnings are insignificant as compared to men's. (Photo by Allison Joyce/Getty Images) MANIKGANJ, BANGLADESH - AUGUST 19: 14 year old Shima Akhter walks through a field near her home August 19, 2015 in Manikganj, Bangladesh. Last year, when she was 13, Shima married an 18 year old man. In June of this year, Human Rights Watch released a damning report about child marriage in Bangladesh. The country has one of the highest rates of child marriage in the world, with 29% of girls marrying before the age of 15, and 65% of girls marrying before they turn 18. The detrimental effects of early marriage on a girl cannot be overstated. Most young brides drop out of school. Pregnant girls from 15-20 are twice as likely to die in childbirth than those 20 or older, while girls under 15 are at five times the risk. Research cites spousal age difference as a significant risk factor for violence and sexual abuse. Child marriage is attributed to both cultural tradition and poverty. Parents believe that it 'protects' girls from sexual assault and harassment. Larger dowries are not required for young girls, and economically, women's earnings are insignificant as compared to men's. (Photo by Allison Joyce/Getty Images) Up Next See Gallery Discover More Like This HIDE CAPTION SHOW CAPTION of SEE ALL BACK TO SLIDE

"An exclusion without exceptions would violate the cultures and traditions of some communities in New Jersey based on religious traditions," Christie said in a statement.

Opponents of the measure said exceptions should remain for marriages of young members of the military - 17-year-olds can enlist with parental consent - and pregnant teenagers.

The bill as it was already approved by both houses of the legislature would have made New Jersey the first state to outlaw child marriage altogether, according to Unchained At Last, a group that opposes arranged and forced marriages.

Most such marriages are underage girls married to older men, it said.

Communities and ethnic groups in the United States known to practice arranged or forced marriage include Orthodox Jews, Muslims, Mormons, Sikhs and Hmongs, according to Unchained At Last.

N.J. Assemblywoman Nancy Munoz, the bill's main sponsor, told the Thomson Reuters Foundation she was disappointed.

"It's not an absolute veto, which is good," she said.

The measure could become law if legislators send it back to the governor with his recommendations.

Studies have shown that child marriage is associated with mental health problems, poverty and increased high school drop-out rates.

The New Jersey bill prompted similar legislation in the states of California, Connecticut, Massachusetts, Missouri, New York, Pennsylvania and Texas. (Reporting by Sebastien Malo @sebastienmalo, Editing by Ellen Wulfhorst. Please credit the Thomson Reuters Foundation, the charitable arm of Thomson Reuters, that covers humanitarian news, women's rights, trafficking, property rights, climate change and resilience. Visit http://news.trust.org)

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