Beaudoin said he thought it was "out of the ordinary" when she asked him to donate. "But I cared about her so much. And I mean, we were, we were in love. I mean, I loved Nadya very much," he told Chris Cuomo in an exclusive interview with "Good Morning America."
Beaudoin said he and Suleman had a "serious" three-year relationship from 1997 to 1999 when he was in his early 20s.
Though he and Suleman never talked about marriage, Beaudoin said when he donated the sperm he thought it would be part of "starting a family" together at some point.
He called Nadya "a really great girl" and thought she would make a good mother. His friends nicknamed her "Giggles" for her laugh.
"She really had a really infectious laugh. You know, just her laugh would, it would make you crack up. It's kind of like she had a real high-pitch, squeaky cartoon voice. And, you know, she was a lot of fun to be around. Just her whole bubbly outward personality was really, really cool," Beaudoin said.
But now Beaudoin said he sees a very different woman, both in appearance and demeanor, than the one he knew.
"She looks different, sounds different. You know, it's just not the Nadya I remember," he said.
Nor did Suleman express a desire to have a lot of children, he said.
"You know, I could say this is something that's all new. The Nadya that I knew, it never, it never came up to have such a huge family. It was just an urge to have a child because she was not able to," Beaudoin said.
Beaudoin said that at the time she first approached him about donating sperm, Suleman told him that she had ovarian cancer and was unable to conceive without the help of a doctor.
Wants to Help If He's the Father or Not
Beaudoin said they had an amicable parting, but said he never heard anything more about Suleman undergoing in vitro fertilization or trying to become pregnant.
Beaudoin said he was "shocked [and] surprised" when he first learned that Suleman had delivered octuplets on Jan. 23.
Suleman has denied that Beaudoin is the father, but he said his multiple sperm donations are cause for a paternity test.
Beaudoin said her word isn't good enough.
"It just seems like a lot of her statements that she's made have been really inaccurate," he said.
"I can't take everything she says for granted. I mean when she initially told me the whole reason why, for donating sperm in the first place, you know was to get pregnant because she was not going to be able to have kids. And it, you know, has turned into this."
Beaudoin said he wants a DNA test just to know the truth. Regardless of the children's paternity, Beaudoin said he is willing to help the single mother of 14 raise the children because he does not believe she can handle it on her own.
"Either which way, you know, know that if she needs it I'll lend a helping hand," he said. "She needs help. I mean it's hard. It's hard nowadays to raise two kids, let alone 14."
Beaudoin said he is coming forward now because he knew his name would eventually surface as the potential father and, considering the negative publicity surrounding Suleman, he wanted to tell his story first.
Beaudoin said he tried to reach out to Suleman but she never returned his calls. Now a business owner with a wife and two sons, Beaudoin said the entire ordeal has been very hard on his family.
"You know my wife, she's not real happy about, you know, the whole situation. I mean, you can't really blame her. I mean I kind of threw this in her lap after, you know, it kind of hit the news," he said.
Though he said they dated for three years, Beaudoin now believes Suleman was married at the time.
Controversy Surrounds Suleman
ABC News has learned through San Bernardino Superior Court Records that Suleman, 33, divorced her husband, Marcos Gutierrez, in January 2008.
The divorce document indicates "no children of the marriage," suggesting that Gutierrez was not the father of Suleman's previous six children.
When asked if Suleman, who lives with her parents and collects food stamps, could handle raising another eight children, the possible biological father said, "No."
Suleman made headlines in late January when news that she delivered eight viable babies was heralded as a medical marvel.
In the days that followed the Jan. 23 delivery, critics raised a host of questions about the single mother who had previously given birth to six other children, all of whom had been conceived through artificial insemination, and about her ability to financially support 14 children.
Suleman is unemployed and lives in a three-bedroom home with her parents, who have publicly criticized their daughter's decision to have so many children.
Property records show Suleman's mother, Angela, owns the home and is $23,225 behind in her mortgage payments. The house could be sold at auction beginning May 5.
Suleman told NBC that she does not intend to go on welfare. Earlier this month, her then-publicist said Suleman already receives $490 a month in food stamps and child disability payments to help feed and care for her six other children.
At least one of those children is believed to have autism.
Critics also have attacked a fertility doctor for implanting eight embryos in Suleman's womb during her attempts to get pregnant.
"I'm really angry about that," Angela Suleman told RadarOnline. "She already has six beautiful children. Why would she do this? I'm struggling to look after her six. We had to put in bunk beds, feed them in shifts and there's children's clothing piled all over the house."
Suleman and her parents have not publicly named the sperm donor or the fertility doctor who implanted her with the embryos.
Earlier this month, Suleman told NBC's "Today" that a single doctor helped her conceive all 14 children.
While she did not reveal the identity of the doctor, a 2006 report by television station KTLA shows a grateful Suleman praising the work of Beverly Hills physician Michael Kamrava, who runs a fertility practice. In the report, he says that he used a controversial procedure that he claims makes it much easier to implant women with embryos.
Since the birth of the octuplets -- who were born nine weeks premature at Kaiser Permanente Hospital in Bellflower, Calif. -- a number of fertility experts and bioethicists have criticized Suleman and her physician for dangerously implanting so many embryos.
"Anyone who transfers eight embryos should be arrested for malpractice," said University of Pennsylvania bioethicist Arthur Caplan.
Studies have shown that the tendency toward premature delivery and low birth weight in multiple-birth babies puts them at greater risk for a variety of complications, including respiratory problems at birth, cerebral palsy, birth defects, sensory disorders and even death. These risks increase as the number of babies in the multiple birth increases.
A California-based nonprofit called Angels in Waiting has offered Suleman round-the-clock care and a place to stay with her 14 children. It would cost about $135,000 a month to provide the 12 caretakers necessary for the children, money that would have to come from public donations.