Rheumatoid arthritis affects childbearing choices

NEW YORK (Reuters Health) - The lower birth rate among women with rheumatoid arthritis (RA) may reflect decisions by these women to limit family size, results of a recent study suggest, rather than any reduction in fertility.

Dr. Patricia P. Katz, of the University of California, San Francisco, studied 411 married women with RA, who completed structured telephone interviews regarding childbearing history and decisions.

At the time of the interview, the women were an average of 62 years old, ranging from 19 to 92 years, and had had arthritis for an average of 20 years.

Overall, 6 percent of the women were diagnosed with rheumatoid arthritis before the age of 18 years, 50 percent were diagnosed between the ages of 19 and 44 years, and 44 percent were diagnosed at 45 years or older.

Katz reports in the medical journal Arthritis and Rheumatism that 91 percent of the women had at least one pregnancy, and 85 percent reported at least one live birth. On average, the women had 2.7 pregnancies and 2.3 live births. Most of the women had their last child when rheumatoid arthritis was already diagnosed.

Women who were diagnosed before the age of 18 years or before the birth of their first child had fewer pregnancies and fewer births compared with women diagnosed after having at least one child.

While only 33 women (8 percent) reported being advised to limit family size, 83 (20 percent) said that rheumatoid arthritis had affected their childbearing decisions.

"Women who were advised to limit their family size had significantly fewer pregnancies (2.1 versus 2.8) and fewer children (1.5 versus 2.3) than women who were not advised to limit family size," Katz writes.

"Likewise, women who reported that rheumatoid arthritis affected their childbearing decisions were not less likely to have any pregnancy or any children, but had significantly fewer pregnancies (1.9 versus 2.9) and children (1.5 versus 2.4) than women whose childbearing decisions were not affected by RA."

These findings suggest that the lower rates of childbearing among women with rheumatoid arthritis is due -- at least in part -- to woman's decision to limit the number children, rather than decreased fertility.

SOURCE: Arthritis and Rheumatism, April 15, 2006.