A Florida couple has sued their fertility doctor after a DNA test allegedly showed that sperm from another man was used to create their IVF baby.
Natalie Strong, 36, and Joshua Strong, 53, welcomed a daughter last year following two rounds of in vitro fertilization at Brown Fertility Associates in Jacksonville.
According to the couple’s lawsuit, a routine blood test performed on the newborn showed that she had B-positive blood.
Natalie has O-negative blood, while Joshua has A-negative blood. The couple says those blood types make it biologically impossible for them to have a child with a positive blood type together.
On Thursday, the couple filed a negligence lawsuit against the fertility clinic and its doctor, Dr Samuel Brown, alleging that the wrong sperm was used to create their embryos.
“The report confirmed that Natalie is the biological mother of the daughter she carried and delivered, conceived from the embryo Brown Fertility transferred into her body, and that Joshua is not the biological father,” the court filing states.
“There is only one possible conclusion: Brown Fertility used the wrong sperm.”
At a press conference Thursday announcing the lawsuit, the Strongs said discovering that their daughter was not biologically related to Joshua shattered the joy of welcoming their newborn, First Coast News reported.
Natalie, 36, and Joshua Strong, 53, say they learned through a routine blood test that Joshua was not the biological father of their baby girl
The couple conceived through IVF at Brown Fertility, but learned after the birth that their daughter’s blood type was biologically inconsistent with both of theirs
“It took away the euphoria of having a baby. I mean, this is going to affect us for the rest of our lives,” Natalie said.
“It’s a daily struggle with the emotional aspect of it because you do have sadness and anger, and in the same day you also have joy and love,” Joshua added.
The couple alleges that they paid “tens of thousands of dollars” to Brown Fertility in an effort to have biological children together, according to the lawsuit.
Joshua had previously undergone a vasectomy and therefore needed an invasive sperm-retrieval procedure for the IVF treatment, the lawsuit states.
“Joshua submitted to invasive surgery to retrieve sperm that, somewhere between the freezer and the petri dish, was substituted with the sperm of a man Brown Fertility cannot identify,” the filing alleges.
The lawsuit says the couple created seven embryos. Natalie miscarried after the first embryo transfer, but the second transfer resulted in a full-term pregnancy, and she gave birth on June 5, 2025.
The couple is seeking $50,000 in damages and wants the clinic to account for what happened to Joshua’s sperm.
“We want to know what happened to his sperm. We want to make sure it was not used anywhere else,” Natalie said.
The baby has B-positive blood, while Natalie has O-negative blood and Joshua has A-negative blood. Additional testing allegedly showed that Natalie is the biological mother, but Joshua is not the father
The couple filed a negligence lawsuit Thursday against the fertility clinic and Dr Samuel Brown, alleging that the wrong sperm was used to create their embryos
The couple’s attorney, Rob Marcereau of the Fertility Law Group, told Our News Outlet they want to hold the clinic accountable and help prevent others from going through what they did.
‘The Strongs filed this lawsuit to get answers and hold Dr. Brown and his clinic accountable for what happened,’ Marcereau said.
‘By sharing their story publicly, they also hope to help prevent another family from going through the same thing.’
Our News Outlet contacted Brown Fertility and Dr Brown for comment.
