But pregnancies should be closely monitored, researchers say
TUESDAY, Oct. 6 (HealthDay News) -- Most female and male childhood cancer survivors have normal pregnancies and healthy children, according to two U.S. studies.
Treatments -- chemotherapy, radiation and surgery -- that save the lives of children with cancer may affect their future reproductive health. As the number of childhood cancer survivors increases, it's becoming increasingly important to identify possible problems, including the effects on their babies, the study authors pointed out.
In one study, researchers looked at 1,898 infants born to women diagnosed with cancer before they were 20 and compared them with 14,278 infants born to women who didn't have childhood cancer.
Infants born to the childhood cancer survivors weren't at increased risk for birth defects or death, but were 54 percent more likely to be born preterm and 31 percent more likely to weigh less than 2,500 grams (5.5 pounds) at birth. However, the infants weren't at increased risk for being small for gestational age, the study authors noted.
The researchers also studied infant outcomes by type of mother's cancer and treatments.
"Risk of preterm delivery was greatest after leukemia but also was associated with lymphoma, bone tumors, soft-tissue sarcomas and an abdominal primary cancer site. Among treatment exposures, chemotherapy was associated with a twofold increased risk of preterm delivery, but relative risks were significantly increased for most other modalities as well," wrote Beth A. Mueller, of the Fred Hutchinson Cancer Research Center and the University of Washington in Seattle, and colleagues.
Rates of diabetes, preeclampsia and anemia during pregnancy were similar in both groups of women. But diabetes was more common among bone cancer survivors; anemia among brain tumor survivors and those treated with chemotherapy; and preeclampsia among those treated with a combination of chemotherapy, surgery and radiation.
"Children and adolescents with cancer can be reassured that we did not find an increased risk of malformations or infant death among their first subsequent offspring," the researchers concluded. "The increased occurrence of low birth weight and preterm delivery among childhood cancer survivors and of preterm delivery among young genital tract carcinoma survivors that we and others have observed may indicate relatively less severe potential problems among offspring. However, these outcomes can still greatly affect families, are associated with significantly increased costs and indicate a need for close monitoring of pregnancies among childhood and adolescent cancer survivors."
The study appears in the October issue of the journal Archives of Pediatrics & Adolescent Medicine.
Another study in the same issue of the journal looked at 470 children of men who had childhood cancer and found that the infants had a "borderline risk" of weighing less than 2,500 grams at birth, especially if their father had cancer at an early age or underwent chemotherapy.
"However, they were not at risk of being born prematurely, being small for gestational age, having malformations or having an altered male to female ratio," wrote Dr. Eric J. Chow, of the Fred Hutchinson Cancer Research Center, and colleagues.
In general, female partners of male childhood cancer survivors weren't at increased risk for pregnancy complications, the study found. However, women did have a higher risk of preeclampsia if their male partner had certain types of childhood cancer, especially brain tumors.
"Most pregnancies resulting in live births among partners of male childhood cancer survivors were not at significantly greater risk of complications versus comparison subjects. However, our findings of increased low birth weight and preeclampsia associated with some diagnostic groups raises the possibility that prior cancer therapy may affect male germ cells (cells that will become sperm) with effects on female partners and progeny of male survivors," the study authors concluded.
The Nemours Foundation has more about childhood cancer.
-- Robert Preidt
SOURCE: JAMA/Archives journals, news release, Oct. 5, 2009
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