Sixty to ninety millilitres every two hours, around the clock, is not really a sleep question. It is a question about feed volume and feed pattern that happens to show up loudest at 2 am. The AAP's formula-feeding guidance puts a baby of this age at "6 to 8 ounces (180–240 mL) at each of 4 or 5 feedings in 24 hours" — so your daughter is taking roughly a third of that per feed, about three times as often. Her total for the day may be perfectly adequate. The pattern is the finding.
And the question you actually asked, answered straight: formula does not make babies sleep through. A 2015 study of 715 mothers of babies aged six to twelve months found "no difference in night wakings or night feeds ... between mothers who were currently breastfeeding or formula feeding".
Not medical advice — consult your pediatrician for guidance specific to you and your baby.
What a Six-Month-Old's Formula Day Usually Adds Up To
The authorities differ here, and it is worth knowing whose number you are being quoted: some give a per-feed range, others a daily amount per kilo.
| Whose figure | What it actually says |
|---|---|
| AAP, per feed | 180–240 ml at each of 4 or 5 feedings in 24 hours by 6 months |
| AAP, per day | about 2½ oz (75 ml) a day per pound of body weight, and "babies don't need more than 32 ounces of formula in 24 hours" |
| CDC, how often | formula or solid foods "about 5 to 6 times in 24 hours" at 6 to 12 months |
| NHS, per day | around 150 to 200 ml per kilo of weight a day, stated "until they're 6 months old" |
Two things follow. The NHS weight-based range is written for the window up to half a year, so a baby of exactly this age sits at its edge — a sanity check, not a target to chase. And the per-pound average and the daily ceiling are different rules: the AAP gives the average, then adds that babies "don't need more than 32 ounces of formula in 24 hours" and that one always wanting much more or much less is worth discussing with your pediatrician.
Now put your daughter's day through it. Twelve feeds of 60 to 90 ml comes to roughly 720 to 1,080 ml in a day, which overlaps the 720 to 1,200 ml that the AAP's four-or-five-feed pattern implies. On volume alone she is probably getting enough. What is unusual is the number of sittings: the CDC expects "about 5 to 6 times in 24 hours" at this age, and she is at double that.
Why the Pattern Is the Finding, Not the Total
Feeding little and often is not a fault in itself — NHS guidance says babies "tend to feed little and often, so they may not finish their bottle". What is worth noticing at six months is that it has not consolidated at all. A top-up every two hours means she is rarely properly hungry and rarely properly full. Appetite never gets the runway to build, so each feed only buys the two hours until the next one — which is exactly what you are seeing at night.
This is also where the family chorus starts: a heavier bottle at bedtime, a spoon of cereal in it, a late top-up before everyone sleeps. Set that aside; the lever is earlier in the day.
The Daytime Is the Lever, Not the Night
These are principles rather than a timetable. Your daughter's weight and growth curve are unknown to us, so a prescribed feed schedule is not ours to write — that conversation belongs with your paediatrician.
- Aim for bigger volumes offered less often, in daylight hours. Let her finish on her own terms: the CDC's instruction is to watch for fullness cues "and then stop, even if the bottle is not empty".
- Keep feeding a hungry baby. Stretching the day does not mean refusing a feed — the CDC is explicit that you "continue feeding your baby when they show signs of hunger".
- Expect the gap to be earned, not imposed. NHS guidance is blunt about this: "having a big feed does not mean your baby will go longer between feeds".
- Let food start carrying some of the load. WHO notes that around six months "an infant's need for energy and nutrients starts to exceed what is provided by breast milk, and additional (complementary) foods are necessary" — if solids have not begun, our first-week guide to starting solids in India is the next thing to read, because it changes the arithmetic of the whole day.
Be clear-eyed about what a consolidated day buys you, though. In that 2015 study, babies given more milk or solid feeds during the day "were less likely to feed at night but not less likely to wake". Fewer, bigger daytime feeds is a reasonable thing to aim at. A silent night is not the guaranteed prize.
Whoever is on duty at night — you, your husband, or both of you in shifts — should work from the same volumes and the same prep rules, which we cover in storing and warming formula safely.
So Will She Sleep Through?
Eventually, and later than most people around you will imply. A 2018 cohort study of 388 infants found that "27.9% to 57.0% of 6- and 12-month-old infants did not sleep through the night", using a definition of either six or eight hours of uninterrupted sleep. In the 2015 study, 78.6% of babies aged six to twelve months still regularly woke at least once a night. Waking at this age is ordinary, not a sign that something has gone wrong.
The myth that formula changes this is persistent and specific, and so is its cousin: the CDC states plainly that "putting infant cereal or other solid foods in your baby's bottle will not make them sleep longer", and that it adds a choking risk. For what the phrase "sleeping through" even means and realistic timelines, see our piece on when babies start sleeping through the night. If the waking is about the feed being her way back to sleep rather than hunger, the nearest thing we have is our guide to loosening the feed-to-sleep association — written for breastfeeding, so read it for the principle rather than the specifics.
When This Is a Paediatrician's Question, Not a Routine Change
Book a visit, rather than tinkering with timings, if any of this applies:
- Weight is faltering. NICE's thresholds for concern are falls across weight centile spaces on the growth chart, including "a fall across 2 or more weight centile spaces, if birthweight was between the 9th and 91st centiles" — and your paediatrician has the plotted chart.
- The daily total is low, not just split up. The AAP's line is that a baby always seeming to want much more or much less than the usual daily amount is something to discuss with your pediatrician.
- Feeds come with distress. NHS Start4Life lists "being unsettled during feeding", "crying and not settling" and "not gaining weight" among the signs of reflux, and says to talk to your pharmacist, GP or health visitor if a baby has difficulty feeding or refuses to feed. Small, frequent, reluctant feeds can be a comfort pattern around discomfort.
- Feeds take a very long time. NICE asks clinicians to consider "ineffective bottle feeding" and the "feeding patterns or routines being used" from the feeding history and direct observation of a feed — a long, hard, unproductive feed needs trained eyes, not a new schedule.
Keep a plain two-day log before you go: time, millilitres offered, millilitres taken. That single sheet of paper will tell your paediatrician more than any description of the nights.
