Investigative Unit

San Leandro-Born Woman Takes DNA Test, Finds Out Father is Mom's Fertility Doctor

Following the woman’s search for answers and siblings, the Investigative Unit speaks with the doctor about keeping the secret from the family - until he was confronted.

NBC Universal, Inc.

“I was proud to be Mexican. I was proud of my dad’s family. Like, I was Daddy’s little girl as a little girl.”

In pigtails and, when she got older, thick-rimmed 80s glasses, the resemblance between Marlena Velasquez and her mother is strong. And, if you didn’t have a reason to question it, the man in all her childhood photos was her father.

But, even as a little girl, Velasquez says something seemed off.

“They’d be like, ‘You’re not Mexican.’ And I’d be like ‘Yes, I am!’” Velasquez recalled.

Proving her ethnicity, and the backfire

To prove her ethnicity to her childhood naysayers, Velasquez took an Ancestry DNA test at 40 years old.

“I remember I was really impatient. I just wanted to prove to everybody that I am Mexican, and he is my dad,” she said.

Marlena Velasquez and family.

In a matter of weeks, the results came in on her phone.

With a European mother and a Mexican father, Velasquez was shocked to see she had no Mexican DNA in her. And the surprise didn’t stop there. Scrolling through the list of relatives on the app, she saw a last name that rang an eerie bell.

The name rang an eerie bell

“Because he’s on my birth certificate. I was like [expletive],” she said.

The last name belonged to her mother’s San Leandro fertility doctor. She and her sister knew the name well because their parents were relatively open about their fertility issues. They were under the impression their mother was artificially inseminated with her father’s sperm. So, Velasquez never questioned the man who raised her was her biological father.

Wanting to find answers, Velasquez reached out to people identified as close relatives through the Ancestry app.

More siblings

She found a half-brother in Washington who says his mother was also a patient of the same doctor. He was born in 1974, seven years before Velasquez. Both Velasquez and this half-brother were born at Vesper Memorial Hospital in San Leandro.

Vesper Memorial Hospital in San Leandro, Calif.

Then there’s Velasquez’s sister, the one she grew up with. They both believed their dad was their dad. A DNA test confirmed they are full siblings, meaning, not only did the fertility doctor use his own sperm on a patient at least three times, he did it at least twice with the same family. Their mother got pregnant four times in fact with this fertility doctor, Velasquez said. Two resulted in miscarriages.

The Velasquez sisters want to publicize the doctor's name, but he hasn’t been charged with a crime or named in a lawsuit. In the 1970s and 1980s, when many of these cases happened, there was no law directly criminalizing this act. There is a law in California now, but the statute of limitation is three years.

“[Marlena] kept texting me saying your results are in and I’m like, dude, just be quiet. I haven’t looked at them. Don’t say anything. And I opened it, and I looked at it and I just kind of started crying,” Marlena’s sister said.

Velasquez’s sister said she is too disturbed by this case to reveal her identity. There was a time their mother recommended the doctor be her OB/GYN.

“He was in San Leandro. I remember when I got pregnant with my daughter and mom was like ‘He’s a wonderful doctor,’” she said.

‘I was blocked.’

With questions that needed answers and both parents deceased, Velasquez decided to reach out to the doctor.

“I found the number, and I left a message,” she said. “I just basically said, ‘I have questions. Did my parents know you’re biologically my father?’ And I was blocked.”

“It made me mad…because what was the point of blocking me? I never harassed him. I called him once time to ask him questions,” she said.

It was shortly after that point, Velasquez reached out to the NBC Bay Area Investigative Unit.

Velasquez reaches out to Investigative Unit

Over the course of six months, our team verified the doctor’s name on Velasquez’s birth certificate, found the San Leandro hospital where she was born no longer exists and her mother’s medical records were likely destroyed due to routine hospital records maintenance.

Investigative Reporter Candice Nguyen examined Velasquez's case for six months and spoke with the accused doctor.

The Investigative Unit’s Candice Nguyen tracked down and spoke with the now-retired physician who currently lives out-of-state. When she asked if he would speak with Velasquez, he agreed.

The doctor declined our team’s request to record the conversation, but he told Velasquez that he remembers her case.

He said her parents arranged for an anonymous donor. Back in the 1970s and early 1980s, fertility clinics didn’t normally freeze sperm, so they needed a live donor. Apparently, the day of her mother’s procedure, the donor did not show up. So, the doctor said, he stepped in as favor and used his own sperm.

He said he did not tell her parents or anyone else at the medical office.

“I believe it was only once.” – Accused Doctor

When NBC Bay Area asked if he ever did this again, the doctor said he “believes it was only once, but it was so long ago…”

When Investigative Reporter Candice Nguyen later told him she found two other cases – the half sibling in Washington and Velasquez’s sister – the doctor wrote, “My apologies – it seems that the sands of time have erased items that I am not proud of. However, math and science are impossible to argue with.”

Accused doctor's email to the Investigative Unit. He's now retired.

When asked how many times he used his own sperm with unknowing patients, he said, “only ones whose donors did not show.”

How many times did donors fail to show? That’s when the doctor ended our communication over email.

Accused doctor ends communication with NBC Bay Area.

“Like, [that information] didn’t really give me anything. Because either he really can’t remember, or he just doesn’t want to get himself in trouble,” Velasquez said.

Her sister is angrier.

“I want it to be known what he’s done. I’m sure there could be so many more people out there,” she said.

You can watch part 2 of this investigation here. To reach Candice Nguyen about this story or another, e-mail her at

A woman said that when she took an at-home DNA test, she learned her biological father is her mother’s San Leandro fertility doctor. Raj Mathai speaks with Investigative Reporter Candice Nguyen.
Contact Us