Female patients can conceive and deliver healthy babies after undergoing allogeneic hematopoietic cell transplantation (alloHCT), despite fertility challenges posed by treatment, reveals a recent study published in Blood.
AlloHCT involves transplanting stem cells from a healthy donor to individuals with hematologic cancers or benign hematologic disorders like leukemia and sickle cell disease. Advances in alloHCT procedures have increased long-term survival rates, particularly in young adults aspiring to have children. Nevertheless, risks to fertility persist due to transplant-related complications, extended medication use, and previous exposure to total body irradiation or potent chemotherapies.
“Fertility is crucial for young female patients,” mentioned Katja Sockel, MD, senior physician at University Hospital Carl Gustav Carus Dresden in Germany, and lead researcher. “Some patients may forego certain treatments due to fertility concerns. For young adults who survived cancer, normalizing life involves planning for a family.”
In the largest systematic study on adult female alloHCT recipients, Dr. Sockel and her team retrospectively analyzed data from the German Registry for Stem Cell Transplantation to evaluate pregnancy and birth rates and identify risk factors in females aged 18 to 40. Out of 2,654 participants, 50 women had 74 pregnancies, resulting in 57 live births, with a median time of 4.7 years from transplantation to first pregnancy.
The likelihood of pregnancy was higher in women aged 18 to 35 at the time of alloHCT, with an average pregnancy age of 29.6 years. Although the initial birth rate for this group was over six times lower than the general German population, this study disproves the notion that pregnancy post-alloHCT is implausible. While some pregnancies were aided by assisted reproductive technology (ART), 72% resulted from natural conception.
Some participants refrained from pregnancy prevention measures due to believing conception was unattainable as advised by their doctor. Natural pregnancies should not be underestimated, and females should be informed about potential fertility restoration post-alloHCT to avoid unplanned pregnancies.
A few factors increased the chances of a first live birth, including a less aggressive conditioning regimen, transplants for non-malignant conditions, and minimal or no total body irradiation. Maternal complications arose in 25 out of 52 pregnancies, primarily vascular (in 16 pregnancies) such as preeclampsia, edema, and hypertension. While not exceeding general population risks, close monitoring by transplant physicians and gynecologists is crucial to avert maternal complications.
Fetal outcomes from 44 pregnancies were positive, with no elevated rates of childhood illnesses or developmental delays compared to the general population. However, preterm delivery and low birth weight incidence were elevated in this group. Ten pregnancies experienced preterm delivery, most occurring between gestation weeks 28 and 32. Six newborns had low birth weights, and one had very low birth weight. Overall, the live birth rate was 78%, akin to the general population.
“The study affirms that female alloHCT recipients can have successful and safe pregnancies,” added Dr. Sockel. “These findings aid in counseling young women and promoting awareness and funding for various ART methods post-alloHCT, enabling patients to lead a normal life.”
Some study limitations stem from its retrospective design, lacking data on fertility markers pre-alloHCT, challenges in gathering detailed participant information retrospectively, and dependency on self-reported pregnancy outcomes which might underreport unsuccessful pregnancies. Moreover, certain ART options were unavailable during the study period.
Researchers anticipate prospective studies will enhance understanding of how pre-alloHCT treatments and new therapies influence fertility in young cancer patients, guiding more personalized therapies balancing anti-tumor efficacy, reduced toxicity, and preserved fertility.
