Five things you will notice that nobody has ever counted
Molding, caput, breast swelling, sneezing and irregular breathing have no published prevalence at all. That absence is worth knowing.
This guide has a rule: where no reliable figure exists, it says so rather than borrowing one from a textbook. This topic is that rule in action, because five of the things new parents notice most often have no published prevalence anywhere.
These five have no number. Searches of the medical literature for this guide found no study that puts a population prevalence, with a denominator, on any of them.
| What you will see | What is known | Published prevalence |
|---|---|---|
| Molding, the cone-shaped or lopsided head | Described clinically as near-universal after a vaginal birth; resolves over days | None found |
| Caput succedaneum, the soft puffy swelling on the scalp | Searches returned only studies of forceps and vacuum outcomes, none reporting how often it happens | None found |
| Breast swelling in the newborn, sometimes with a drop of milk | Only single case reports of infection were found, which are not prevalence | None found |
| Sneezing | No prevalence literature located at all | None found |
| Irregular or periodic breathing in a healthy term baby | Everything found concerned premature or intensive care babies, not healthy term ones | None found |
You will find confident percentages for all five on parenting websites and in textbooks. None of them could be traced back to a primary study for this guide, so none is printed here. The absence is itself the finding: five of the commonest things parents notice about a newborn have never been properly counted.
Two things that do have a number, but not an American one.
Fast breathing in the first day. A German population study covering 239,971 single term live births in two federal states from 2001 to 2005 found 1,423 babies diagnosed with transient tachypnoea of the newborn, which is 5.9 per 1,000 term single babies. That is about 1 in 170 (that conversion is arithmetic done here). It is self-limited by definition. It was commoner after a cesarean done before labour started, at lower gestational ages, and in boys. No US population figure exists for it that could be verified, so this one is labelled German.
Vaginal bleeding in newborn girls. A 1976 German study of 350 newborn girls found visible bleeding in 3.3%, with traces detectable by laboratory methods in 25.4%. It occurred always in the first week, with its highest frequency on the 5th day of life
and was regarded as a physiologic event. That paper's own safety rule, quoted exactly: if any genital bleeding lasts longer than one week or appears for the first time after that period, further diagnostic procedures are essential as a possible pathologic condition may be assumed.
This is a 1976 study of 350 babies and it is the only prevalence figure that could be verified anywhere; no modern or US figure exists. Read it as its date.
"Is there actually evidence on how common that is, or is it just something everyone says?"
"How long should it take to settle, and what would make you want to see us sooner?"