This test is done at weeks 26 to 28 to check for gestational diabetes (high blood sugar during pregnancy), which increases the risk of having a too-large baby and needing a C-section.
Group B Streptococcus
At 36 weeks or so, you’ll be tested for the presence of potentially dangerous bacteria that could be passed to the baby during delivery. It involves a painless swab of your rectum and vagina.
Issues to Consider
Perhaps the biggest issue surrounding prenatal testing is what you would do if a problem were detected.
“Women think they have to terminate, but that’s not true,” McFarlin says. “You can continue the pregnancy and use that time to educate yourself about the baby’s condition, talk to other families dealing with the same issue, maybe even prepare for the delivery.” For instance, if the baby will need surgery for a heart malformation at birth, you can find a hospital with that capability and deliver there.
Testing involves many such big decisions—ones that your doctor may not be able to discuss at length. “A discussion about prenatal testing can take up to an hour, time that many doctors just don’t have,” O’Brien says, adding that knowing all the details of the various tests may not even be within their area of expertise. As a result, many doctors routinely refer patients to a genetic counselor, who specializes in this area. One important note: If a diagnostic test indicates a problem, get a second opinion from a perinatal (high-risk) specialist.
Choosing Not to Test: “I feel like knowing about a problem before you have the child and can do anything is torture.”
Even though she was going to be 39 when her baby was born, Liz Lane and her husband, Brent, decided at the outset that they wouldn’t do any prenatal testing. Not only were they confident that they would not terminate a pregnancy under any circumstances, but Liz felt that if they did find out about a problem, her pregnancy would be marred by sadness and stress.
Their doctor advised the San Diego-area couple to meet with a genetic counselor to discuss their risks, but they decided against this, too. They did, however, have an ultrasound. “We wanted to find out the gender, and the doctor wanted to check on same basic things, such as whether the cord was wrapped around the baby’s neck,” Liz says. “But I told him that if he found a genetic or other problem, we didn’t want to know.”
The doctor did tell the Lanes that if he were to detect a problem that would require special care after delivery, he would be beholden to let them know. But he found nothing wrong, and baby Robin was born full term, in perfect health, in January 2010.