Five things worth worrying about

There are plenty of things new moms fret over—Why isn’t my baby rolling over yet? Shouldn’t she be sleeping through the night? Is it normal to cry whenever strangers try to hold her?—but most aren’t worth a second thought. (She’ll roll over eventually—and sleep through the night eventually, too. Yes, separation anxiety is common.) But there are a few scenarios that are cause for concern …
Fever in an infant under 2 months old.
If your newborn has a fever of 100.4 or higher, go immediately to the emergency room. (Take note: Only a rectal thermometer can give you an accurate reading at this age.)
Poor eating.
Infants become dehydrated easily, and being undernourished even for a short period can impact development. After the first week, a baby should be able to drain a breast or empty a bottle in 15-20 minutes. Any longer, and she’s using more energy than she’s taking in. Other warning signs: Your baby is sweating or working harder to breathe while eating.
Bloody, mucus-y or clay-colored stools.
Blood in the stool could be fine if it’s caused by a tear around the anus. If you can’t see one or the blood persists, call your doctor. Greasy or mucus-y stools should be brought to doc’s attention within a few days. Gray or whitish stools warrant an immediate call to the pediatrician; they might indicate a rare liver disorder.
Movements and nonmovements.
Call baby’s health care provider if you notice that your baby stops moving part of her body, is moving a part less than before, or is moving it less than the corresponding part. (For example, if she is moving the right arm less than the left arm.) Also phone your practitioner if your baby drops her head down for short episodes (1 to 3 seconds) and then brings it back up, sometimes with her arms involved and usually in clusters of 10 or so at a time.
Late social milestones.
Physical milestones are less important in the long term than social milestones. Your baby should be able to smile socially by 2 months, learn to be charming or “flirt” for attention between 4 and 6 months, and share things of interest by 1 year (by pointing or looking from something of interest to see if others are looking).