When a Baby Needs Help at Birth: Is "Milking" the Cord Safe for Their Development?

A large trial followed babies to age 2 to answer a question many parents never knew was being asked

When a baby is born limp and not breathing well, the medical team has only seconds to act — and one of the choices they make is what to do with the umbilical cord. A large study called MINVI tested gently squeezing, or "milking," the cord to push a little extra blood into the baby, versus clamping the cord right away. Following these children to age 2, researchers found that milking the cord did not change how the children were developing compared with early clamping [1]. Combined with the earlier finding that milking reduced the need for resuscitation and lowered the risk of birth-related brain injury, this suggests that cord milking is a safe, simple, no-cost step for these newborns.

Why This Question Matters

Before a baby is born, a surprising amount of their blood is not yet in their body — it is still in the placenta and the umbilical cord. In the last several years, doctors and midwives around the world have shifted toward waiting at least half a minute to a minute before clamping the cord, so that more of this blood can flow into the baby. This "delayed cord clamping" is now recommended in national guidelines [2], and it is especially helpful for babies born very early, where a large trial found it improved survival [3]. For healthy full-term babies, the extra blood boosts iron stores, and one study even suggested small benefits in movement and social skills years later [4].

But there is a group of babies for whom this simple "just wait" advice runs into a problem: the babies who are born limp, pale, and barely breathing — what doctors call "nonvigorous." These babies may need help right away, and waiting 30 to 60 seconds at the cord competes with the urgent need to help them breathe. For years, this was an unresolved tension. Milking the cord was proposed as a clever middle path: instead of waiting, the team squeezes a length of the cord toward the baby a few times, delivering the extra blood in just a few seconds, so that help can begin immediately.

The Worry That Had to Be Ruled Out

Milking was not adopted without caution. In the most premature babies — those born around 23 to 27 weeks — a trial had to be stopped early because milking was linked to more bleeding in the brain than slow clamping [5]. The fragile blood vessels of a very premature baby's brain may not handle the quick "push" of blood well. Because of this, milking is not used in the tiniest, earliest babies. The open question was whether milking was safe for bigger, more mature babies — those born at 35 weeks or later — whose brains and blood vessels are much sturdier. Their short-term results looked good, but no one had followed these children long enough to know whether milking might quietly affect how they grew and developed. That is the gap this study set out to close.

How the Study Worked

The MINVI trial took place at 10 hospitals in the United States, Canada, and Poland [6]. It included babies born between 35 and 42 weeks of pregnancy who were nonvigorous at birth. Each hospital used one approach — cord milking or early clamping — for a period of time, then switched to the other, so the two groups could be fairly compared. With cord milking, the team milked about 20 centimeters (roughly 8 inches) of cord four times over a couple of seconds. With early clamping, the cord was clamped within 60 seconds.

For this follow-up, families were asked to fill out two well-known checklists when their child was about 2 years old [1]. One, called the Ages and Stages Questionnaire, asks parents about their child's communication, movement, problem-solving, and social skills. The other screens for early signs that a child might be at higher risk for autism. Out of 1,730 babies in the original trial, about 971 children (roughly 8 in 10) had development results at age 2, and 927 completed the autism-risk screen. Researchers counted children who had died as having the lowest possible score, so the comparison would not overlook any serious outcomes.

What They Found

The two groups looked essentially the same at age 2 [1]. The overall development scores were identical between children who had cord milking and those who had early clamping. None of the individual skill areas — talking, moving, problem-solving, or getting along with others — showed a real difference. The autism-risk screening was also very similar: about 9 in 100 children in the milking group and 8 in 100 in the early-clamping group scored in the higher-risk range, a difference small enough to be due to chance. Checklists done earlier, at 6 and 12 months, pointed the same way. Importantly, no new safety problems showed up.

Put simply: the earlier study had shown that milking helped these babies in the first days of life — fewer needed breathing support, and fewer developed the kind of oxygen-related brain injury that can require cooling treatment. This new study shows that those early benefits did not come with any hidden cost to the children's development two years down the road.

It also helps to understand why the researchers were so careful about this particular group of babies. A baby who is struggling to breathe is already in a vulnerable moment, and any new practice — even a gentle one — deserves close scrutiny before it becomes routine. By comparing hundreds of children who had cord milking with hundreds who had early clamping, and by following them for two full years, the study was large enough and long enough to catch a meaningful difference if one existed. The fact that the two groups looked so alike, across several different measures and at several different ages, is what gives the reassurance its weight. A single lucky-looking result at one checkup could be chance; the same steady picture at 6 months, 12 months, and 2 years is much harder to explain away [1].

What This Means for Families

If your baby is born needing help and the team milks the cord, this research offers real reassurance. It means the team is giving your baby some of the blood still waiting in the placenta, quickly enough that they can also start helping your baby breathe — and that, at age 2, children who had this done were developing just like those who didn't. Cord milking costs nothing, needs no special equipment, and takes only seconds. It is exactly the kind of simple, practical step that can make a difference in a tense moment. National resuscitation guidelines now say that milking the cord "may be reasonable" for these older newborns [2], and this study strengthens the case.

It is worth being honest about the study's limits. Most of the families were from well-resourced hospitals, and many of the mothers had attended college, so the findings apply most directly to similar settings. Most of these babies were not severely ill — nearly three-quarters never needed intensive care. In parts of the world where birth-related oxygen problems are far more common, the picture could look different, and researchers are careful not to over-promise. The checklists parents filled out are good screening tools but not the most detailed possible tests of development, which is a reason to keep studying these children.

Parents sometimes wonder whether "extra" blood could be too much of a good thing. It is a fair question. The blood that flows in from the placenta is the baby's own blood, and the amounts involved are small and natural — the same blood the baby would have received had the cord not been clamped so quickly. The main thing doctors watch for afterward is jaundice, the yellowing of the skin that can happen when a baby has more red blood cells to process; this is common in newborns, easy to check for, and treatable. In this study, the babies who had cord milking ended up with slightly higher blood counts, as expected, and this did not lead to any new problems. Knowing what the team is watching for can make the process feel less mysterious and more like the careful, routine care it is.

A Note on History and What Comes Next

For a long time, the choice of what to do with a struggling newborn's cord was made without good evidence — teams simply clamped quickly and moved on, because that felt safest. Over the past decade, careful trials have gradually shown that the extra blood from the placenta matters, first for premature babies and then, with milking, for babies who need immediate help [7]. Earlier, smaller studies of milking in premature babies had hinted there was no long-term harm, but they were too small to be sure [8],[9]; milking in full-term babies born by cesarean had also been tested [10]. This trial is the largest and clearest look yet at what happens to these children as they grow.

What are researchers working on next? A similar study is now underway in lower-resource countries (where more babies are born needing help), to see whether the same benefits and the same reassuring safety hold true there [11]. Scientists also hope to follow children beyond age 2, into their school years, since the extra iron and cells from placental blood could have effects that only become clear later [4]. For now, families can take comfort in a clear message: for a baby who needs help at birth, milking the cord is a gentle, no-cost step that helps early on and shows no downside two years later.

References

  1. Katheria AC, El Ghormli L, Clark E, et al. Two-Year Outcomes of Umbilical Cord Milking in Nonvigorous Infants: A Secondary Analysis of the MINVI Randomized Clinical Trial. JAMA Netw Open. 2024;7(7):e2416870. doi:10.1001/jamanetworkopen.2024.16870 ↩
  2. Yamada NK, Szyld E, Strand ML, et al; American Heart Association and American Academy of Pediatrics. AHA/AAP focused update on neonatal resuscitation. Pediatrics. 2024;153(2):e2023065030. doi:10.1542/peds.2023-065030 ↩
  3. Tarnow-Mordi W, Morris J, Kirby A, et al; Australian Placental Transfusion Study Collaborative Group. Delayed versus immediate cord clamping in preterm infants. N Engl J Med. 2017;377(25):2445-2455. doi:10.1056/NEJMoa1711281 ↩
  4. Andersson O, Lindquist B, Lindgren M, Stjernqvist K, Domellöf M, Hellström-Westas L. Effect of delayed cord clamping on neurodevelopment at 4 years of age: a randomized clinical trial. JAMA Pediatr. 2015;169(7):631-638. doi:10.1001/jamapediatrics.2015.0358 ↩
  5. Katheria A, Reister F, Essers J, et al. Association of umbilical cord milking vs delayed umbilical cord clamping with death or severe intraventricular hemorrhage among preterm infants. JAMA. 2019;322(19):1877-1886. doi:10.1001/jama.2019.16004 ↩
  6. Katheria AC, Clark E, Yoder B, et al; Milking in Nonvigorous Infants group. Umbilical cord milking in nonvigorous infants: a cluster-randomized crossover trial. Am J Obstet Gynecol. 2023;228(2):217.e1-217.e14. doi:10.1016/j.ajog.2022.08.015 ↩
  7. Liyanage SK, Ninan K, McDonald SD. Guidelines on deferred cord clamping and cord milking: a systematic review. Pediatrics. 2020;146(5):e20201429. doi:10.1542/peds.2020-1429 ↩
  8. Rabe H, Sawyer A, Amess P, Ayers S; Brighton Perinatal Study Group. Neurodevelopmental outcomes at 2 and 3.5 years for very preterm babies enrolled in a randomized trial of milking the umbilical cord versus delayed cord clamping. Neonatology. 2016;109(2):113-119. doi:10.1159/000441891 ↩
  9. Katheria A, Garey D, Truong G, et al. A randomized clinical trial of umbilical cord milking vs delayed cord clamping in preterm infants: neurodevelopmental outcomes at 22-26 months of corrected age. J Pediatr. 2018;194:76-80. doi:10.1016/j.jpeds.2017.10.037 ↩
  10. Erickson-Owens DA, Mercer JS, Oh W. Umbilical cord milking in term infants delivered by cesarean section: a randomized controlled trial. J Perinatol. 2012;32(8):580-584. doi:10.1038/jp.2011.159 ↩
  11. Katheria A, Szychowski J, Carlo WA, et al. Umbilical cord milking versus delayed cord clamping in infants 28 to 32 weeks: a randomized trial. Pediatrics. 2023;152(6):e2023063113. doi:10.1542/peds.2023-063113 ↩