When Sledge got pregnant several years later, her Johns Hopkins lupus doctor enrolled her in a study. The study wasn't of a medication - Sledge's lupus was under control enough that she wasn't on any - but a formal, intensive observation of how her disease progressed as her pregnancy did. If it became necessary to take medication, doctors would also closely monitor how her body and her baby reacted to it.
In the meantime, they took blood, did many ultrasounds, and did other weekly tests starting in the third trimester.
Sledge, now 29, says she hoped participating in the research would help her as well as other women with lupus. Even noninvasive studies like the one she enrolled in are uncommon and can have trouble recruiting patients.
"I thought it was a great opportunity to provide some additional information for women who also have the disease," she said.
Her sons - 2-year-old Conor and 7-month-old Logan - were both born healthy at St. Joseph Medical Center in Towson.
Sledge's obstetrician, Dr. Judith Rossiter, head of obstetrics and gynecology at St. Joseph, said the gold standard of medical research - the random, prospective, double-blind clinical trial - just isn't feasible in most cases when it comes to testing drug safety in pregnancy. The risks are too high.
"I don't see that changing in our lifetime because of liability," she said. "If anything goes wrong with the pregnancy, our society is one that is more likely to blame the medication."
Many women can't stop treating their illnesses just because they get pregnant, doctors say. Some guidance is available, based on observational studies. But those are often small, allowing few general safety conclusions to be drawn. The FDA has a labeling system that addresses risks, but it is being reworked after years of criticism that it is misleading and oversimplified.
After fetal harm, one of the biggest problems with giving medication during pregnancy is determining an optimal dose, one that confers the most benefit and least risk. Under current practice, determining that has been nearly impossible. Changes in the body of a pregnant woman alter how the body processes drugs. Take chemotherapy - some cancer drugs are metabolized and excreted so quickly in pregnant women that they may get all of the risk and none of the benefit, researchers say.
