Intelligence outcomes, memory, attention, and behavior measures were normal at the group level at 9 years of age for children born to mothers with cancer, according to Frederic Amant, MD, PhD, head of gynecologic oncology at the University of Leuven in Belgium, and colleagues. Study results, published in the Journal of Clinical Oncology, also showed individuals scoring below the normal range were more likely to have been born prematurely.
“In the long run, children do not seem to suffer from antenatal exposure to chemotherapy,” Dr. Amant said. “This underscores the potential to treat pregnant women with cancer, rather than inducing pre-term birth, termination of pregnancy, or delay of maternal treatment.”
Maternal cancer during pregnancy is concerning because of the potential for effects directly from treatment, as well as indirect environmental and psychosocial effects in the pre- and post-natal periods. Researchers with the International Network on Cancer, Infertility and Pregnancy – with participants in Belgium, the Netherlands, Italy, Czech Republic, and New Jersey – previously found that the general outcomes for children were favorable, but that at 6 years, prenatally exposed children had lower verbal intelligence and visuospatial long-term memory scores, and that chemotherapy was associated with poorer emotional regulation.
The present analysis involved 151 children, including seven pairs of twins, born to 144 mothers with either hematologic (n=27) or solid tumors (117). Researchers identified the following groups for analysis: fetal exposure to chemotherapy only or in combination with other therapies (n=109, 72.2%), surgery only (n=18, 11.9%), radiotherapy (n=16, 10.6%), trastuzumab (n=1), or no treatment (n=16, 10.6%). Researchers found that group outcomes for intelligence, verbal and visuospatial memory, attentional function, and behavioral measures were within the normal ranges. There were no differences in the Full Scale Intelligence Quotient (FSIQ) between boys and girls, treatment types, or stage of cancer.
They found, however, that individual children who scored below the normal range were more likely to have been born pre-term, with the average FSIQ score increasing by 1.6 points for each week of increase in gestational age (GA) at birth (p<0.001).
“GA also explained verbal intelligence, performance intelligence, and processing speed [p=0.002, 0.002, and 0.009, respectively],” researchers noted.
Researchers also found that maternal bereavement had an effect. The FSIQ was lower in children whose mother died before they turned 2 compared to children with a surviving mother. When researchers adjusted for gestational age, this association disappeared: children whose mother died before they turned 2 also tended to be born earlier.
When researchers looked specifically at children who were prenatally exposed to chemotherapy, no significant associations were found with FSIQ when parental education levels were taken into account.
Dr. Amant said avoiding pre-term births should be a priority.
“Cancer treatment during pregnancy is the best way to prevent prematurity,” he said. Even one cycle of chemotherapy, he noted, “may add a few weeks that the fetus can stay with its mother.”
He said the previous findings of lower scores at 6 years of age, contrary to the findings seen in this analysis of 9-year-olds, could have had to do with differences in control groups.
“The effects are small, and the choice of control group may influence this,” he said.
Overall, the findings offer an encouraging view of neurocognitive development for children whose mothers have cancer, researchers said.
After 9 years of age, it is “rather unlikely” new deficits would emerge, Dr. Amant said.
“The observation that these children do well at 9 years is very reassuring,” he said. “As children become older, external influences are more likely to [affect] the outcome parameters.”
Any conflicts of interest declared by the authors can be found in the original article.
Van Assche IA, Veld EA, Calsteren KV, et al. Cognitive and behavioral development of 9-year-old children after maternal cancer during pregnancy: a prospective multicenter cohort study [published online ahead of print, 2023 Jan 12]. J Clin Oncol. doi: 10.1200/JCO.22.02005.