A Choice at 18, a Son at 44: How Sheba Restored Kassandra’s Fertility After 23 Years

When Landon was born on September 9, 2026, it marked a milestone in fertility medicine. It’s believed that the ovarian tissue that made his birth possible had been frozen for the longest storage period to have resulted in a live birth. Once returned to Kassandra’s body, the tissue began working again, restoring the ovarian function that cancer treatment had taken from her more than two decades earlier and opening the way to pregnancy through IVF. 

For young people undergoing treatment that could impact their fertility, her story shows that a decision made during illness can keep the possibility of parenthood alive for decades.

A Decision Made in Hope

Kassandra was 17 and studying for her A-levels in the UK when she was diagnosed with Hodgkin lymphoma in October 1999. After a period of remission brought on by chemotherapy, her disease returned aggressively in 2001. Her doctors needed to perform a bone marrow transplant immediately to give her the best chance possible, but saving her life didn’t leave enough time for Kassandra to undergo an egg retrieval procedure. 

Even so, Kassandra wasn’t ready to give up on the possibility of one day having her own children and continued asking questions. Martyn Blayney, Senior Embryologist and Laboratory Manager at Bourn Hall, put forward an experimental option, and within 48 hours the arrangements were in place. On May 2, 2001, surgeons at Addenbrooke’s Hospital removed a small amount of her ovarian tissue, and the team at Bourn Hall froze it with cryopreservation technology.

At the time, there was no certainty that frozen ovarian tissue could ever lead to a pregnancy, but Kassandra held out hope. “My hope was remarkably simple: I was only 18, and I had time on my side. I had to trust that one day, when I was ready to become a mother, science might have caught up with what had been preserved for me.“

Years of Searching

Kassandra survived cancer a second time and went on to build a full life in London, with a career in digital banking, close friendships, and a long-term relationship with her partner, Daniel, becoming a stepmother to his older children. However, once the couple was ready to expand their family in 2015, at 33, tests confirmed she was menopausal. The tissue she had frozen over ten years earlier as a precaution now held her only chance of having a biological child.

Finding a team capable of bringing that possibility to fruition took almost another decade. Specialists in both the UK and Belgium turned her away because her tissue sample lacked documentation that only became a requirement long after it was frozen. The pioneering procedure considered a long shot in 2001 had become a barrier to restoring her fertility once Kassandra was ready to have a child of her own.

Eventually, her efforts to find a team with the expertise she needed brought her to Dr. Sara Matthews, a specialist in reproductive medicine and surgery. “She never promised me an outcome, but she believed my case was worth pursuing and persevered with me in finding a way forward,” Kassandra says. Together, they expanded the search overseas and found Prof. Dror Meirow.

Turning to the Experts

Prof. Meirow, a world-renowned expert in fertility preservation, first published a proof of concept with his colleague, Prof. Joshua Dor, in the New England Journal of Medicine in 2005 showing that ovarian tissue transplantation could restore fertility. Based on a set of early cases demonstrating the team’s precision and expertise, the Israeli Ministry of Health recognized the procedure as non-experimental, making Sheba the first center in the world to receive this status. Since 2010, Prof. Meirow and his team at the Josef Buchmann Gynecology and Maternity Center have continued to put what was once theory into practice, performing 106 transplants that resulted in 41 live births. 

Follow-up studies showed that none of the women who underwent the procedure at Sheba experienced a cancer relapse. That safety record rests on careful screening. Because malignant cells can still remain present in cryopreserved ovarian tissue, Sheba’s specialized laboratory evaluates each sample before transplantation, using histopathology, immunohistochemistry, cytogenetic analysis, molecular testing, and xenotransplantation. More than 100 patients with different malignancies, including high-risk cases such as leukemia, have undergone this evaluation. 

From Bourn Hall to Tel HaShomer

At Sheba, a single dedicated team performs every transplant, follow-up, and fertility treatment according to a standardized protocol led by Prof. Meirow, caring for women from around the world looking for a path forward. With specific authorization from the Israeli Ministry of Health, Kassandra prepared to become one of them, as her tissue made the journey from Bourn Hall to Sheba in May 2023. 

The team tested an initial thawed fragment and found no cancer cells and good follicles, clearing her for transplantation. She booked flights for the end of September, but the events of October 7 and their aftermath put the procedure on hold. For almost a year, Kassandra worried about the tissue stored in Israel. “It wasn’t simply frozen tissue to me; it represented my one chance of becoming a mother,” she says.

In May 2024, at 42, Kassandra was finally able to travel to Sheba with her mother, who has been a constant source of support throughout her life. Prof. Meirow performed the laparoscopic transplant using samples frozen for just over 23 years. He placed two pieces of thawed tissue into Kassandra’s ovaries, atrophied after more than a decade of menopause, and a third in a pelvic peritoneal pocket.

Despite her worries before the trip, Kassandra felt safe and supported throughout her stay. “I was made to feel so assured, so safe,” she recalls. Her connection with the team, especially her Global Patient Services coordinator, Galit, has continued well beyond the procedure. “It’s like I have a friend overseas now. We text and I show her pictures of Landon.”

A Long-Awaited Arrival

After coming home, Kassandra welcomed another return on December 4, 2024: her first menstrual cycle in years. The tissue removed before her cancer treatment as a teenager had begun functioning again more than two decades later.

However, yet more challenges lay ahead. After trying to conceive naturally, Kassandra moved on to IVF with Dr. Matthews in London. Her first egg collection produced no eggs, later cycles yielded just two embryos, and the first transfer was unsuccessful. On December 15, 2025, she transferred her final embryo, created from an egg that had matured overnight in the laboratory. A positive pregnancy test followed on Christmas Day, her father’s birthday. After everything they had been through, she and Daniel let themselves believe it only gradually, with each scan and passing week.

Landon David was born on September 9, 2026. Kassandra describes him as healthy, thriving, and beautiful. His middle name honors her father, and for the entire family, Landon stands for strength, a long journey, and remaining steadfast.

A Family Decades in the Making

No two journeys are the same; still, Kassandra hopes her story will raise awareness of fertility preservation among young people facing cancer treatment. 

She sees her happy family, now complete, as the culmination of an extraordinary chain of people, from Martyn Blayney’s foresight in 2001 and Dr. Matthews’ determination, to the expertise of Prof. Meirow and his team at Sheba, along with the embryologists, clinicians, scientists, nurses, laboratory staff, and coordinators who cared for her tissue across more than two decades. “Twenty-five years ago, nobody could promise me that the ovarian tissue being frozen would ever give me a child. Today I can look at my son and know that it did.”

Her story reflects the combination of medical expertise, innovation, and patient-centered care that continues to change lives at Sheba Medical Center.