cribsheet by Emily Oster – key takeaways

Each chapter ends with a brief section, title The Bottom Line which summarizes the main takeaways from that chapter.

1. The First Three Days

Newborn baths early on are unnecessary but not damaging. Tub baths are better than sponge baths.
Rooming in doesn’t have any compelling affects on breastfeeding outcomes, either way. It is worth being careful about falling asleep with your infant if you choose to keep them with you at all times.
Infant weight loss should be monitored an compared with expectations; you can do this yourself at www.newbornweight.org
Jaundice is monitored with a blood test and should be treated if outside the normal range. www.bilitool.org
Delayed cord clamping is likely recommended.
Vitamin K supplements are a good idea.
Eye antibiotics are likely unnecessary for most babies but have no down sides.

Swaddling has been shown to reduce crying and improve sleep. It is important to swaddle in a way that allows the baby to move its legs and hips.
Colic is defined as excessive crying. It is self limiting, meaning it will stop eventually. Changing formula or maternal diet, treatment with a probiotic, or both, have show some positive impacts.
Collecting data on your baby is fun! But not necessary or especially useful.
Exposing your infant to germs early on risks their getting sick, and the interventions for a feverish infant are aggressive and typically include a spinal tap. Limiting germ exposure may be a good idea even if just to avoid these interventions.

Return to exercise can typically start within a week or two and most women could be back to their pre-pregnancy routine by 6 weeks.
Sex is ok, but use contraception.

The benefits to breastfeeding early on are more limited than is commonly stated.
There are likely some long term health benefits for mom regarding breast cancer.
The data does not provide strong evidence for long-term health or cognitive benefits of breastfeeding for your child.

Skin to skin contact early on can improve likelihood of breastfeeding success.
On latching:
- nipple shields work for some women, although they can be hard to quit.
- there is very little evidence that fixing a tongue tie or lip tie can improve nursing.
On pain:
- fixing a tongue tie can reduce pain for mom
- there isn’t much evidence on how to fix nipple pain but focusing on the latch may help.
- if you are still in pain a few minutes into a feeding or a few weeks into nursing, get help; it could be an infection which would treatable or some other problem with a solution.
On nipple confusion: not supported in the data.
On milk supply: the majority of women will have their milk come in within 3 days after birth, but for about 1/4 it will take longer.
- the biological feedback loop is compelling: nursing more should produce more supply.
- evidence on the effectiveness of non-drug remedies (e.g. fenugreek) on supply is limited.

There is good evidence that infants that sleep on their back are at lower risk for SIDs
There is moderate evidence that bed sharing is risky.
There is less good evidence that room sharing is beneficial.
- benefits to room sharing diminish after the first few months.
- infant and child sleep may be better if your child sleeps alone after the first few months.
Sleeping on a sofa with an infant is extremely dangerous.

With any child care arrangement quality matters. For day care in particular, use some simple tools to do evaluate.
On average more time in day care seems to be associated with slightly better cognitive outcome and slightly worse behavior outcomes.
The positive effects of day care present more at older ages, the negative ones more at younger ages.
Kids in day care develop more immunity but get sick more often.
Parenting quality overrides childcare choices.

Cry it out methods are effective.
These methods improve outcomes for parents including less depression and better general mental health.
There is no evidence of long or short term harm to infants; if anything there may be some evidence of short term benefits.
There is evidence of success for a variety of methods and little to distinguish between them. The most important thing is consistency.

Early exposure to allergens reduces incidences of food allergies.
Kids take time to get used to new flavors, so it is valuable to keep trying a food even if they reject it at first, and early exposure to varying flavors increases acceptance.
There is not much evidence behind the traditional food introduction recommendations; no need to do rice cereal first if you do not want to.
Baby lead weening doesn’t have magical properties, but there is no reason not to do it if you want to.
Vitamin D supplementation is reasonable but don’t freak out about missing a day here and there.

Delayed motor development can be a signal of more serious issues, the most common is cerebral palsy.
Variation in motor development within the very wide normal range is not a cause for concern.
There are many approaches to evaluating motor skills; your pediatrician is your best partner in doing so.
Children get about 1 cold per month for the winter at least until school age.

There are some standard tools to determine child vocabulary size. There are also some metrics you can compare.
Girls develop faster than boys.
Timing of language development does have some link with later test scores and readings, but the predictive power is weak for any individual child.

Age at toilet training has increased over time, very likely as a result of parents choosing to train later.
Starting training earlier leads to early completion on average, although it generally takes longer; starting intensive training before 27 months does not seem to lead to earlier completion.
There is little evidence on the efficacy of child lead training vs more intensive, goal oriented methods.
Toilet refusal is a common situation, but challenging to overcome.

Consistent rewards and punishments and avoiding parental anger is important. Examples include “1,2,3 Magic” and “The Incredible Years”.
Don’t spank

There is some support for the value of reading to your child starting in infancy.
Whether your 2 or 3 year old can read is unclear, but it would be very unusual for them to be a fluent reader.
Evidence on the value of different preschool philosophies is limited. School quality is the most important thing.

Unequal division of labor and less sex probably play some role decreased marital satisfaction.
There is some evidence suggesting marital counseling and marriage check-up programs can improve happiness.