Women who experience severe gestational hypertension may give birth to boys at lower risk for testicular cancer, although the exact reasons why are still unclear, according to a paper published in the November 1, 2008, issue of Cancer Research, a journal of the American Association for Cancer Research.
Andreas Pettersson, M.D., a doctoral student at Karolinska Institute in Sweden, said the protective effect of gestational hypertension may be due to the hormones that are released when a placenta malfunctions.
"Ironically, a malfunctioning placenta may lower the risk," said Pettersson. "One possible reason is that estrogens are lower in pregnancies that develop severe gestational hypertension or preeclampsia, and this lack of estrogens may lower the risk of testicular cancer."
Pettersson and colleagues observed 293 cases of germ-cell testicular cancer in the Swedish Cancer Register and 861 controls in the Swedish Medical Birth Register. They extracted data on maternal and pregnancy characteristics such as gestational hypertension, proteinuria, anemia and glucoseuria.
If women experienced severe gestational hypertension, their male offspring were 71 percent less likely to develop testicular cancer than those women who experienced no hypertension. If the gestational hypertension was mild, there was a 62 percent increased risk of testicular cancer.
Beyond decreased estrogen, severe gestational hypertension and preeclampsia increases the level of human Chorionic Gonadotropin, another pregnancy-related hormone, which may also have a protective effect against testicular cancer.
Pettersson said that these findings add knowledge to the mechanisms behind testicular cancer, but he cautioned against reverse thinking.
"This study does not suggest that a woman who does not have gestational hypertension is going to give birth to a boy who is at increased risk for testicular cancer," said Pettersson.
Source: American Association for Cancer Research