Chemotherapy during pregnancy reported safe for developing fetus
The diagnosis of cancer has a devastating impact on anyone who receives it. However, the news is even more devastating to a woman who happens to be pregnant at the time. In the past decade, chemotherapy during pregnancy has become more acceptable within the medical community; however, fetal damage has been an ongoing concern.
To explore this situation, Belgian researchers conducted a long-term study of children born to mothers who underwent chemotherapy during their pregnancy. They recorded the general health, cardiac function, and neurodevelopmental outcomes of the children. Their findings were published online on February 10 in the journal Lancet Oncology.
The study group was comprised of 68 pregnancy outcomes from multiple locations: 70 children were delivered at an average gestational age of 35.7 weeks (range: 28.3-41.0; 47 women delivered at less than 37 gestational weeks). The children were evaluated at birth and age 18 month; then at ages 5-6, 8-9, 11-12, 14-5, or 18 years. The researchers conducted clinical neurological examinations, tests of the general level of cognitive functioning (Bayley or intelligence quotient (IQ) test), electrocardiography, and echocardiography; in addition, a questionnaire evaluated general health and development. From age 5 years, the researchers also conducted audiometry (hearing test), the Auditory Verbal Learning Test, and subtasks of the Children's Memory Scale, and the Test of Everyday Attention for Children. Also beginning at age 5, the researchers completed the Child Behavior Checklist.
The women underwent 236 cycles of chemotherapy; the median follow-up period of was 22.3 months (range: 16.8-211). The researchers found that although neurocognitive outcomes were within normal limits, cognitive development scores were lower for children who were born preterm compared to those born at full term. When controlling for age, sex, and nation, the score for IQ increased by an average 11.6 points for each additional month of gestation. The measurements of the children's behavior, general health, hearing, and growth were comparable to those of the general population. Cardiac dimensions and functions were within normal limits. The authors found a severe neurodevelopmental delay in both members of one twin pregnancy.
Premature birth was very common in this group of women: 66% of the women delivered before 37 weeks of gestation. The authors noted that the high rate of prematurity that was observed in the study was not caused by chemotherapy; rather it was related to the strategy of delivering the infant as soon as it became viable and then initiating chemotherapy. In a few cases, the decision to deliver early was based on the mother's deteriorating health. Overall, 28 infants (74%) were delivered preterm iatrogenically (a physician’s decision to induce labor or perform a cesarean section), at a median gestational age of 35.3 weeks (range, 31.3 to 36.3).
The authors concluded that fetal exposure to chemotherapy was not associated with increased central nervous system,, cardiac, or auditory morbidity; in addition, they found no impairment of general health and growth compared with the general population. However, they noted that subtle changes in cardiac and neurocognitive measurements emphasized the need for longer follow-up. In addition, prematurity commonly occurred and was associated with impaired cognitive development. Therefore, they stressed that physicians should not induce delivery or conduct a cesarean section before term unless the decision was absolutely necessary.
Reference: Lancet Oncology