When a Baby May Arrive Very Early: What a Cesarean Can Mean for the Mother

A plain-language guide to Trahan and colleagues' study of nearly 100 000 US births at 22 to 25 weeks of pregnancy and the health of the mothers who gave birth

When a baby is about to be born between 22 and 25 weeks of pregnancy, families often have to decide whether the birth should be by cesarean section (an operation through the belly and womb). A large US study of nearly 100 000 such births found that mothers who had a cesarean were more likely to have serious complications than mothers who gave birth vaginally, although most mothers in both groups did not have them. Knowing these numbers can help families and doctors decide together.

Why the very earliest births raise such hard questions

The study at the centre of this article, by Dr Trahan and colleagues, looked at a question that is easy to overlook: what happens to the mother when a very early baby is born by cesarean [1]. Until now, conversations with families have tended to focus on the baby, and for good reason.

A full-term pregnancy lasts about 40 weeks. Births from about 20 to 25 weeks are called "periviable", a word meaning "around the edge of being able to survive" [2]; this study looked at births from 22 to 25 weeks. At this stage a baby may or may not live, even with the best intensive care. Very early births are rare, but they matter enormously: according to the main US obstetric organisations, births before the last three months of pregnancy make up only about 0.5% of all births yet account for most deaths of newborn babies [3].

How doctors used to think about cesarean birth this early

About thirty years ago, a study at 11 large US hospitals found that very small babies (1000 grams or less, about two pounds) were more likely to survive when doctors were willing to perform a cesarean. But for babies born before 26 weeks, that willingness also went along with more survivors living with serious health problems [4]. Researchers tried to settle the question with fair-test trials (randomised trials, where a coin-toss-style process decides who gets which treatment) for babies lying bottom-first, but those trials could not find enough families to take part [5]. As a result, practice came to depend heavily on the hospital: in one group of 20 US centres, the share of babies born at 22 to 24 weeks by cesarean ranged from 13% at some hospitals to 65% at others [6].

Over time, care for the tiniest babies improved. In 19 US academic hospitals, about 30 in 100 babies born at 22 weeks who received full intensive care survived to go home, as did about 56 in 100 at 23 weeks [7]. Across the United States, a growing share of babies born at these early ages received full intensive care, with the fastest rise at 22 weeks [8]. Expert groups recommended that families receive information about the benefits and risks of treatments for both mother and baby [2]. In 2017, US obstetric experts advised that decisions should be made case by case and, as the new study's authors explain, that a cesarean for the baby's sake may be considered from 23 weeks, with the mother's risks weighed against any possible benefit to the baby [3][1].

The trouble was that doctors had few reliable numbers for the mother's side. Earlier studies of mothers at these early stages were much smaller; one, which looked back at the hospital records of 678 women, found more womb infections after cesarean [9]. Doctors also knew that cesareans this early often need a vertical cut in the womb, rather than the usual low sideways cut, in about half of cases between 23 and 26 weeks [10], and that such operations can affect future pregnancies [11].

How the new study was done

Researchers from Columbia University in New York and the University of California, San Diego, used a national database of hospital records called the National Inpatient Sample. It captures about one in every five hospital stays in the United States, and statistical weighting lets researchers estimate totals for the whole country [1]. They looked at births of a single baby between 22 and 25 weeks from 2016 to 2022. Twins were left out, as were pregnancies with placenta problems that always require a cesarean.

The records represented about 98 240 births. Of these, 39 595 (about 4 in 10) were by cesarean and 58 645 (about 6 in 10) were vaginal. The researchers compared complications in the two groups of mothers, taking into account differences such as age, other illnesses, pregnancy problems, and the type of hospital.

What the researchers found about mothers' health

Cesareans became much more common the further along the pregnancy was. About 13 in 100 births at 22 weeks were by cesarean, compared with about 37 in 100 at 23 weeks, 52 in 100 at 24 weeks and 55 in 100 at 25 weeks [1]. Mothers who had had a cesarean before, or who had high blood pressure in pregnancy, were more likely to have one. Babies lying in an unusual position, or showing signs of distress on heart-rate monitoring, were also much more common among cesarean births.

For mothers, the key findings were these. Serious complications, such as severe infection spreading through the body (sepsis), shock, or heart and lung problems, happened to about 7 in 100 mothers who had a cesarean, compared with about 3 in 100 who gave birth vaginally. About 5 in 100 mothers needed a blood transfusion after a cesarean, compared with about 2 in 100 after vaginal birth. Around 14 in 1000 needed intensive treatments such as a breathing machine, compared with 4 in 1000. Infection of the lining of the womb (endometritis) affected about 25 in 1000 versus 8 in 1000, and blood clots about 5 in 1000 versus 2 in 1000. Removal of the womb at the time of birth (hysterectomy) was rare, about 6 in 1000 after cesarean compared with 1 in 1000 after vaginal birth, but it is a life-changing operation. Wound infections or breakdown were also more common after cesarean, as might be expected after surgery, although they were too rare after vaginal birth to say exactly how much more common.

One result went the other way: heavy bleeding after birth was recorded less often after cesarean (about 4 in 100) than after vaginal birth (about 7 in 100). The study did not explain why, so this finding should be interpreted cautiously.

The share of very early births delivered by cesarean also crept up over the seven years, by about 1.6% a year.

What these results can and cannot tell us

This kind of study looks at records rather than following people over time, so it shows links, not proof that the cesarean itself caused every complication. Some mothers had cesareans because they were already unwell, and that illness may explain part of the extra risk. The records could not show which type of cut in the womb was used, and they did not include what happened to the babies, so the study cannot say whether a cesarean helped the baby survive. It also could not show effects on future pregnancies. An older study from Washington State found that after a cesarean this early, the womb tore during the next pregnancy in about 18 in 1000 women, compared with 4 in 1000 after a full-term cesarean [11].

What this means for families

If you are facing a very early birth, these findings are not a reason for alarm, but they are a reason to ask questions. Most mothers in both groups did not have serious complications. Still, a cesarean at this stage is a major operation with real risks for you, and you have a right to hear them in plain numbers. It is also reasonable to ask how likely a cesarean is to help your baby at your baby's exact stage of pregnancy, because that benefit is less certain at the earliest weeks.

The same research team has also studied the babies' side of this choice in a separate record-based study of babies lying bottom-first (breech) at 22 to 25 weeks. Fewer of those babies died when they were born by cesarean, while mothers had fewer complications after vaginal birth: about 16 in 1000 mothers after vaginal birth versus 31 in 1000 after cesarean [12]. Because the two groups of babies were not at exactly the same stage of pregnancy, that study cannot say precisely how much a cesarean helps, but it shows why both sides of the scale matter.

Different decisions can be made separately. Steroid injections to help a baby's lungs, for example, are a different choice from having a cesarean, and experts suggest weighing them one at a time [13]. Your plans can also change as things develop. Doctors themselves sometimes see these choices differently from one another [14], so asking both the obstetric team and the newborn team to talk with you together can help. Some families choose comfort-focused care for their baby, and In[Neo]Sight has a guide to perinatal palliative care; another article looks at survival of babies born at 22 to 23 weeks.

What researchers are working on next

The next step is to connect mothers' and babies' records so that families can see, side by side, the likely benefit for the baby and the likely risk for the mother at each week of pregnancy. Researchers also want to record which type of cut was used and to follow mothers into later pregnancies.

The bottom line

Cesarean birth at the very edge of viability is common, becoming slightly more so, and carries higher risks for the mother than vaginal birth, including serious complications, transfusion, infection, blood clots and, rarely, hysterectomy. These numbers give families and their care teams a clearer, fairer picture when making one of the hardest decisions in pregnancy.

References

  1. Trahan MJ, Wen T, Huang Y, et al. Maternal Outcomes Among Periviable Births by Cesarean Delivery. JAMA Netw Open. 2026;9(9):e2634705. doi:10.1001/jamanetworkopen.2026.34705 ↩
  2. Raju TNK, Mercer BM, Burchfield DJ, Joseph GF Jr. Periviable birth: executive summary of a joint workshop by the Eunice Kennedy Shriver National Institute of Child Health and Human Development, Society for Maternal-Fetal Medicine, American Academy of Pediatrics, and American College of Obstetricians and Gynecologists. Obstet Gynecol. 2014;123(5):1083-1096. doi:10.1097/AOG.0000000000000243 ↩
  3. American College of Obstetricians and Gynecologists, Society for Maternal-Fetal Medicine. Obstetric Care consensus No. 6: Periviable Birth. Obstet Gynecol. 2017;130(4):e187-e199. doi:10.1097/AOG.0000000000002352 ↩
  4. Bottoms SF, Paul RH, Iams JD, et al. Obstetric determinants of neonatal survival: influence of willingness to perform cesarean delivery on survival of extremely low-birth-weight infants. National Institute of Child Health and Human Development Network of Maternal-Fetal Medicine Units. Am J Obstet Gynecol. 1997;176(5):960-966. doi:10.1016/S0002-9378(97)70386-770386-7) ↩
  5. Bergenhenegouwen LA, Meertens LJ, Schaaf J, et al. Vaginal delivery versus caesarean section in preterm breech delivery: a systematic review. Eur J Obstet Gynecol Reprod Biol. 2014;172:1-6. doi:10.1016/j.ejogrb.2013.10.017 ↩
  6. Smith PB, Ambalavanan N, Li L, et al. Approach to infants born at 22 to 24 weeks' gestation: relationship to outcomes of more-mature infants. Pediatrics. 2012;129(6):e1508-1516. doi:10.1542/peds.2011-2216 ↩
  7. Bell EF, Hintz SR, Hansen NI, et al. Mortality, In-Hospital Morbidity, Care Practices, and 2-Year Outcomes for Extremely Preterm Infants in the US, 2013-2018. JAMA. 2022;327(3):248-263. doi:10.1001/jama.2021.23580 ↩
  8. Venkatesh KK, Lynch CD, Costantine MM, et al. Trends in Active Treatment of Live-born Neonates Between 22 Weeks 0 Days and 25 Weeks 6 Days by Gestational Age and Maternal Race and Ethnicity in the US, 2014 to 2020. JAMA. 2022;328(7):652-662. doi:10.1001/jama.2022.12841 ↩
  9. Kawakita T, Sondheimer T, Jelin A, et al. Maternal morbidity by attempted route of delivery in periviable birth. J Matern Fetal Neonatal Med. 2021;34(8):1241-1248. doi:10.1080/14767058.2019.1631792 ↩
  10. Osmundson SS, Garabedian MJ, Lyell DJ. Risk factors for classical hysterotomy by gestational age. Obstet Gynecol. 2013;122(4):845-850. doi:10.1097/AOG.0b013e3182a39731 ↩
  11. Lannon SMR, Guthrie KA, Vanderhoeven JP, Gammill HS. Uterine rupture risk after periviable cesarean delivery. Obstet Gynecol. 2015;125(5):1095-1100. doi:10.1097/AOG.0000000000000832 ↩
  12. Gomez Slagle HB, Huang Y, Ananth CV, Reddy UM, Trahan MJ, Friedman AM. Outcomes Among Vaginal Versus Caesarean Periviable Breech Deliveries: A Propensity Score-Matched Study. BJOG. 2026;133(5):942-955. doi:10.1111/1471-0528.70067 ↩
  13. Rysavy MA, Mehler K, Oberthür A, et al. An Immature Science: Intensive Care for Infants Born at ≤23 Weeks of Gestation. J Pediatr. 2021;233:16-25.e1. doi:10.1016/j.jpeds.2021.03.006 ↩
  14. Tucker Edmonds B, Krasny S, Srinivas S, Shea J. Obstetric decision-making and counseling at the limits of viability. Am J Obstet Gynecol. 2012;206(3):248.e1-5. doi:10.1016/j.ajog.2011.11.011 ↩