With Zika spreading across the United States, the fetal fears that began in Brazil have come a lot closer to home. According to The Washington Post, several women have faced the effects of contracting Zika virus during their pregnancies: one woman has already given birth to a baby with severe birth defects, while other mothers have miscarried or chosen to abort fetuses with early signs of abnormalities. Mothers who have Zika or are concerned that they could contract it are facing serious decisions and uncertain futures, leading many to wonder if there are any early signs of microcephaly.

After birth, microcephaly is fairly easy to diagnose, although the severity of the condition varies from infant to infant. According to the Centers for Disease Control and Prevention and the Boston Children’s Hospital, typical microcephaly symptoms after birth include a head with a circumference two standard deviations below the average, failure to thrive, high-pitched crying, low appetite, and involuntary muscle contractions.

While still in utero, however, diagnosing microcephaly isn’t quite as cut and dry. According to the CDC, “Microcephaly can sometimes be diagnosed with an ultrasound test (which creates pictures of the body).” The CDC recommends going for an ultrasound late in the second trimester or early in the third trimester, although women who have contracted Zika should definitely see their physicians and undergo monitoring and regular ultrasounds as soon as possible.