China began adopting Perinatal Definition I in 1981. Over the past half-century, China has made tremendous progress in maternal and child health. Consequently, the definition of the perinatal period should be updated accordingly. The key update lies in the lower limit of gestational age. This limit is directly linked to the concept of "prematurity," which in turn affects the willingness to treat Extremely Preterm Infants (EPIs), leading to the widespread abandonment of EPIs during labor and hindering advancements in rescue technologies. The objective existence of the EPI population presents the critical question: to treat or not to treat? Updating the perinatal definition is a strategic imperative to establish the long-term vision that all viable infants deserve to be "rescued with effort." Meanwhile, the Recommendations on Gradually Transferring the Delivery Site for Extremely Preterm Infantsaddresses the tactical level at this stage, setting the tactical goal of "must rescue" to elevate the lower limit of birth gestation for EPI treatment in China.

The duration of the perinatal period—its starting and ending points—is closely related to government investment in health resources, national education levels, and the quality of medical care. Currently, there are two main international definitions: Perinatal Definition I, spanning from 28 weeks of gestation to 7 days after birth, is mostly adopted by low-income countries; Perinatal Definition II, spanning from 20 weeks of gestation to 28 days after birth, is generally adopted by upper-middle-income countries.

Since the rise of perinatal medicine in China in the late 1970s, the field of maternal and child health has achieved remarkable success. Driven by government policies and academic activities, the duration of maternal and neonatal perinatal care has practically extended beyond the 28-day postpartum limit of Definition II, and antenatal care now begins as early as 6–13 weeks of gestation—earlier than the 20-week threshold of Definition II. However, the perinatal care for preterm infants has failed to break through the lower gestational limit of 28 weeks set by Definition I.

China’s current adoption of Perinatal Definition I severely impacts the treatment of preterm infants born before 28 weeks of gestation, namely EPIs. In countries using Perinatal Definition II, a preterm infant is defined as one born before 37 weeks of gestation, which includes EPIs. Medical staff and society in these countries generally hold a positive attitude toward rescuing EPIs, achieving a discharge survival rate of over 85% a decade ago, with the lowest recorded survival at 21 weeks. Conversely, in countries using Definition I, a preterm infant is defined as one born between 28 and <37 weeks. EPIs are excluded from this category and classified as "late abortuses," leading to prolonged passivity among Chinese obstetricians and pediatricians regarding EPI rescue. Historically, perinatal neonatal death reviews classified EPI deaths as "unavoidable" (i.e., "no need to save"), which was somewhat understandable when modern neonatology was just emerging in the 1990s. However, since the 2010s, China's discharge survival rate for infants ≥28 weeks has reached 96.24%, comparable to upper-middle-income countries, while the survival rate for EPIs has reached approximately 60%. Under these circumstances, allowing the notion of "no need to save" is clearly untenable. Data from Northern China (2010–2019) and Southern China (2018–2022) show that 73% and 77.在2% of EPIs, respectively, were abandoned before admission to the Neonatal Intensive Care Unit (NICU). The failure to rescue a large number of "viable infants" deprives medical staff of necessary practical and research opportunities, severely limiting the improvement of specialized rescue techniques and creating a prominent短板 (shortcoming) in China's perinatal and neonatal fields.

The World Health Organization's 1984 Consultative Report on Definitions and Standards for Maternal and Child Health and the Perinatal Periodproposed: "The perinatal period begins when the fetus is viable." By that time, the United States had already adopted Perinatal Definition II with a lower limit of 20 weeks. However, in the 1990s, the discharge survival rate for EPIs born at 23 weeks in the U.S. was only 15%, and no infants survived at ≤22 weeks. It was under the framework of this definition that the U.S. recommended specific lower limits for EPI resuscitation. Clearly, in international perinatal practice, the perinatal definition differs in significance from the lower limit of birth gestation for EPI rescue; they belong to strategic and tactical levels, respectively. The perinatal definition is strategic—a long-term goal with clear guidance and foresight. The significance of updating China's definition lies in using academic standards to establish the long-term goal that all viable infants should be included in the scope of "effortful rescue," thereby optimizing the internal and external environment for EPI treatment and promoting comprehensive improvements in related perinatal care. In contrast, the lower limit of birth gestation for EPI rescue belongs to the tactical level of "must rescue," serving as a medium- or short-term goal subordinate to the strategic objective. Our recently published Recommendations on the Lower Limit of Birth Gestation and Delivery Sites for Extremely Preterm Infantsrepresents the tactical goal for the current stage, emphasizing that infants born at ≥24 weeks should receive active resuscitation, those born at ≤23 weeks with good vitality may be treated, and advocating the "in utero transfer" model to ensure tiered care.

Although EPIs account for less than 1% of total births, multi-center studies across various provinces in China show their discharge mortality remains high at around 40%. Taking 2024 as an example, with 9.54 million births in China, global data indicating EPIs account for 5.8% of newborns, and assuming a best-in-class international discharge survival rate of 93%, if all Chinese EPIs were admitted to NICUs, approximately 51,460 additional infants could survive. This represents a valuable human resource that cannot be ignored. Regardless of whether the definition is updated, viable EPIs objectively exist; however, an update can guarantee their maximum reasonable treatment in principle. Therefore, updating the perinatal definition to include EPIs within the normative scope of perinatal medicine is crucial for comprehensively elevating China's perinatal and neonatal science and technology and bringing our treatment standards to the forefront of the international community. More importantly, it concerns the protection of the right to life for this group and national demographic security.

The perinatal definition originated with the rise of international perinatal medicine. China's current adoption of Definition I was determined by the First Perinatal Academic Conference of the Obstetrics and Gynecology Branch of the Chinese Medical Association. At that time, the discharge survival rate for infants born at 28–32 weeks in Chinese NICUs was only 5%; the vision and dedication of the pioneers who established perinatal medicine are undeniable. Today, the technical organizations and medical security policy systems related to perinatal neonatal rescue are well-established, and the mortality rate for infants born at ≥28 weeks dropped to 3.1‰ in 2021, reaching the average level of upper-middle-income countries. The timing is ripe to promote the update of China's perinatal definition. We should carry forward the professional spirit of our predecessors and actively facilitate this update to foster an atmosphere of comprehensive improvement in the quality and level of perinatal care.

In summary:

Recommendation 1: Update China's perinatal definition to the internationally recognized Perinatal Definition II, i.e., from 20 weeks of gestation (or total gestational age) to 28 days after birth. This will transform the status of EPI rescue in China from "no need to save" or "not necessary" to "must save," and further elevate it to the realm of "striving to save."

Recommendation 2: Clinical practice for EPI rescue in China should continue to follow the Recommendations on the Lower Limit of Birth Gestation and Delivery Sites for Extremely Preterm Infantsjointly issued by the Chinese Society of Perinatal Medicine and the Neonatologist Branch of the Chinese Medical Doctor Association, to effectively push the baseline of "must rescue" to new heights.

Source: Journal of Developmental Medicine (Electronic Version), May 2026, Vol.14, No.3

Editor: Lily