New insights into the impact of pregnancy on inflammatory arthritis

June 27, 2006

During pregnancy, women with inflammatory arthritis usually experience disease improvement or even remission, while a disease flare regularly occurs within 3 to 4 months after delivery. A study featured in the July 2006 issue of Arthritis & Rheumatism ( sheds light on this widely reported yet little understood phenomenon.

Prenatal diagnostic tests have recently established that fetal cells and cell-free DNA routinely flow into the mother's bloodstream during normal pregnancy. On the strength of these findings, researchers from the Fred Hutchinson Cancer Research Center in Seattle, Washington, supported in part by a grant from the Washington Women's Foundation and by grants from the National Institutes of Health, set out to investigate whether changes in serum fetal DNA levels correlate with changes in arthritis activity during and after pregnancy. They conducted a study on 25 pregnant women with inflammatory arthritis.

Ranging in age from 23 to 43, 17 of the women were classified as having adult-onset rheumatoid arthritis (RA) and 6 were classified as having juvenile idiopathic arthritis (JIA). Of the subjects, 24 had active disease in the 6 months prior to pregnancy, with one experiencing RA onset in her first trimester. 7 of the women were in their first pregnancy, 7 were in their second pregnancy, and 11 had been pregnant at least twice before. None of the patients took a disease-modifying antirheumatic drug during pregnancy, and patients taking prednisone took no more than 10 milligrams per day, with one exception. All pregnancies resulted in a single live birth.

Samples of peripheral venous blood were taken from all subjects, most 3 times or more during the course of pregnancy, as well as postpartum, within 3 months of delivery. Levels of cell-free fetal DNA were measured using real-time quantitative polymerase chain reaction targeting the fetus-specific genetic markers. Women were evaluated for changes in disease activity in each trimester and 3 to 4 months after giving birth.

During pregnancy, 21 of the 25 women - 79 percent of the RA patients and 100 percent of the JIA patients - experienced improvement or remission of inflammatory arthritis symptoms. Among these women, 62 percent showed signs of disease improvement in the first trimester. Once improvement occurred, it was sustained or progressively increased until delivery. Among these women, levels of serum fetal DNA also progressively rose throughout pregnancy. As fetal DNA quantities doubled, the likelihood of arthritis improvement increased 1.2 fold. By the third or fourth month after delivery, disease recurrence was observed in 90 percent of these patients, coinciding with a drop of serum fetal DNA to very low or undetectable levels.

The remaining 4 women, including the one who had RA onset during the first trimester, did not experience significant reduction of disease symptoms during or after pregnancy. For the women with active disease, serum levels of fetal DNA were dramatically lower - and even undetectable in 2 - throughout pregnancy, especially in the third trimester, compared with those women who experienced arthritis improvement.

This study, the first to focus on fetal DNA in women with RA during pregnancy, found a significant inverse correlation between arthritis activity and serum fetal DNA concentration over the course of pregnancy and postpartum. Yet, researchers acknowledge the study's limitations, including its small size, and inability to determine whether serum fetal DNA has any direct biologic effect on inflammatory arthritis or therapeutic value.

"Whether the dynamic changes in fetal DNA reflect the potential for immune modulation of maternal arthritis, are a result of disease activity changes, or are not causally related cannot be determined from these studies," notes researcher J. Lee Nelson, M.D. "If the former, further studies could generate new therapeutic strategies for RA."

Article: "Prospective Study of Fetal DNA in Serum and Disease Activity During Pregnancy in Women With Inflammatory Arthritis," Zhen Yan, Nathalie C. Lambert, Monika Østensen, Kristina M. Adams, Katherine A. Guthrie, and J. Lee Nelson, Arthritis & Rheumatism, July 2006, (DOI: 10.1002/art.21966).


Related Pregnancy Articles from Brightsurf:

COVID-19 has a prolonged effect for many during pregnancy
Symptoms for pregnant women with COVID-19 can be prolonged, lasting two months or longer for a quarter of the women who participated in a national study led by UC San Francisco and UCLA.

Relaxed through pregnancy
A group of researchers from Charité - Universitätsmedizin Berlin have been able to show that maternal psychological wellbeing during pregnancy has a positive effect on newborn infants.

Trajectories of antidepressant medication use during pregnancy
In an analysis of women who started pregnancy when taking antidepressant medications, investigators identified three trajectories of antidepressant dispensing during pregnancy: more than half stopped their treatment, a quarter maintained their treatment throughout pregnancy, and one-fifth discontinued it for a minimum of three months and then resumed it during the postpartum period.

Are women using e-cigarettes during preconception and/or pregnancy?
A new study of 1,365 racially/ethnically diverse, low-income pregnant women found that 4% reported e-cigarette use.

A better pregnancy test for whales
To determine whale pregnancy, researchers have relied on visual cues or hormone tests of blubber collected via darts, but the results were often inconclusive.

Cannabis use during pregnancy
The large health care system Kaiser Permanente Northern California provides universal screening for prenatal cannabis use in women during pregnancy by self-report and urine toxicology testing.

Questions and answers about cannabis use during pregnancy
A new study shows that women have many medical questions about the use of cannabis both before and during pregnancy, and during the postpartum period while breastfeeding.

The effect of taking antidepressants during pregnancy
Exposure to antidepressants during pregnancy and the first weeks of life can alter sensory processing well into adulthood, according to research in mice recently published in eNeuro.

Is ivermectin safe during pregnancy?
Is it safe to give ivermectin to pregnant women? To answer this question, researchers from the Barcelona Institute for Global Health (ISGlobal), an institution supported by 'la Caixa,' conducted a systematic review and meta-analysis of studies that reported cases of accidental exposure to the drug among pregnant women.

Going to sleep on your back in late pregnancy
This study looked at whether going to sleep on your back in the third trimester of pregnancy was associated with average lower birth weights.

Read More: Pregnancy News and Pregnancy Current Events is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to