New findings may help ease concerns for women with lupus who are interested in having a child. A new study concludes that most women with lupus whose disease is not very active will have a safe pregnancy. The results are to publish online June 22 in Annals of Internal Medicine.

It was previously suggested that women with lupus avoid pregnancy because of serious complications to their own health and the health of the baby. As more knowledge became available, doctors told women with lupus to wait until symptoms were under control, but until now, it was still uncertain whether this advice was right and whether pregnancy outcomes would be favorable.

The study identified several risk factors that might put some women with systemic lupus erythematosus (SLE or lupus) at higher risk for bad outcomes in pregnancy. These factors include having active lupus disease, high blood pressure requiring medications for control, low platelet counts, and a positive lupus anticoagulant test result during the first trimester. Being a minority also added risk.

"One of the questions I'm most commonly asked by young women with lupus is whether it is safe to get pregnant," says lead study author Jill. P. Buyon, MD, director of the division of rheumatology and director of the Lupus Center at NYU Langone. "Our new study is quite reassuring in that in the majority of cases, both mother and baby can do well if lupus is under control at conception. For patients who may be facing a complicated pregnancy, we have been able to pin down some of the risk factors."

In this multicenter, multiethnic, and multiracial study -- which is believed to be the largest of its kind -- researchers followed 385 pregnant women with lupus and found that 81 percent of pregnancies were uncomplicated, with fewer than one in five women experiencing at least one poor pregnancy outcome. Also encouraging is that flares of lupus activity were very rare, and most notably, severe flares occurred in only 3 percent of all the women. Furthermore, the study identified factors that help in identifying women at risk for poor outcomes -- and is very reassuring for those who have no risk factors.

According to the National Institutes of Health, between 350,000 and 500,000 Americans may be affected by lupus, an autoimmune disease in which the body's immune system mistakenly attacks healthy tissue, and eventually affect the skin, joints, kidneys, brain, blood elements, and other organs. Flares can be rashes, fever, and arthritis pain and swelling that can range from mild to serious, followed by periods of remission.

The disease most often starts in people in their 20s and 30s and occurs 10 times more often in women than in men, according to the American College of Rheumatology . Lupus tends to be more common in black, Hispanic and Asian individuals. Pregnancy issues are important because most lupus patients have normal fertility.

Participants in the study were women between ages 18 and 45 enrolled in the Predictors of Pregnancy Outcome: Biomarkers in Antiphospholipid Antibody Syndrome and Systemic Lupus Erythematosus (PROMISSE) Trial between September 2003 and December 2012 from eight U.S. sites and one in Canada. All were enrolled during the first trimester of pregnancy. The PROMISSE trial, funded by the National Institute of Arthritis, Musculoskeletal and Skin Diseases of the National Institutes of Health (Grant # RO1 AR49772), began in 2003 under principal investigator Jane Salmon, MD, director of the Lupus and APS Center of Excellence and Collette Kean Research Chair at the Hospital for Special Surgery in New York. Dr. Salmon is the senior author on the study.

Women were examined by researchers at the start of the trial, and during the second and third trimesters of pregnancy, to determine whether disease flares occurred.

Bad pregnancy outcomes included premature birth (9 percent), fetal death during the second or third trimester (4 percent), infant death because of problems with the pregnancy (1 percent), and very low birth weight (10 percent).

Dr. Buyon cautions that the findings may not apply to those with very active disease at conception, for example those with very high levels of protein in the urine because of ongoing uncontrolled kidney disease. Such patients were excluded from this study, and they are typically advised to forestall pregnancy planning until the disease is under better control. In addition to Dr. Buyon, the authors of this study were Mimi Y. Kim, ScD; Marta M. Guerra, MS; Carl A. Laskin, MD; Michelle Petri, MD, MPH; Michael D. Lockshin, MD; Lisa Sammaritano, MD; D. Ware Branch, MD; T. Flint Porter, MD, MPH; Allen Sawitzke, MD; Joan T. Merrill, MD; Mary D. Stephenson, MD, MSc; Elisabeth Cohn, BA; Lamya Garabet, MD; and Jane E. Salmon, MD.