The tiniest babies: a registry of survivors with birth weight less than 400 grams

The Tiniest Babies Registry: A registry of survivors born weighing less than 400 grams

The Tiniest Babies Registry was launched in the year 2000 as a web-based registry for patients who survived to discharge after being born with birth weights below 400 grams. The registry began with 15 patients and by January 2022 had grown to 291, ranging in birth weight from 212 to 399 grams and in gestational age from 21 to 34 weeks. Three patients were born in the 1930s, and no others were born until 1985. The greatest number in a single year was 21 in 2010. The infants were born in 16 countries, but 166 of 291 (57%) were born in the U.S. All except 10 of the infants were small for gestational age at birth. No systematic data on the long-term outcomes of these patients is available, but the information submitted by selected registry participants indicates they are at increased risk for continued delays in growth and development.

Case Report: Treatment of Extremely Preterm Infants With Birthweight Below 300 g: Case Series

Reports on the birth of infants weighing <300 g are quite rare and little is known about the best practices in treating such micropreemies. Therefore, we report here on three cases of low birthweight infants weighing <300 g, of whom two infants survived. The birthweights and gestational ages were ranging 279-293 g and 22 + 6/7 - 23 + 6/7 weeks, respectively. All the infants had severe fetal growth restriction and prematurity. The infant in case 1 died of hepatic rupture, perhaps due to birth trauma, which emphasized the need for less invasive obstetric procedures including en caul delivery. The infant in case 2 managed to survive through severe prematurity secondary to hydrops fetalis. However, complications followed soon as tracheal granulation tissue was formed with neurodevelopmental impairment. The infant in case 3 was born recently and her clinical course was less remarkable without severe complications, despite having the least gestational age and birthweight among the three patients. The improved care protocols for extremely low birthweight infants over these years through experiential learning including that with cases 1 and 2 may have ensured the better outcome of case 3. Accumulating evidence and recording the experience of such cases with continuous constructive discussion can contribute to better outcomes and appropriate parental counseling for extremely small babies in the future.

Outcomes of Extremely Preterm Infants With Birth Weight Less Than 400 g

IMPORTANCE

Birth weight (BW) is an important predictor of mortality and morbidity. At extremely early gestational ages (GAs), BW may influence decisions regarding initiation of resuscitation.

OBJECTIVE

To characterize outcomes of liveborn infants with a BW less than 400 g.

DESIGN, SETTING, AND PARTICIPANTS

This retrospective multicenter cohort study analyzed extremely preterm infants born between January 2008 and December 2016 within the National Institute of Child Health and Human Development Neonatal Research Network. Infants with a BW less than 400 g and a GA of 22 to 26 weeks were included. Active treatment was defined as the provision of any potentially lifesaving intervention after birth. Survival was analyzed for the entire cohort; neurodevelopmental impairment (NDI) was examined for those born between January 2008 and December 2015 (birth years with outcomes available for analysis). Neurodevelopmental impairment at 18 to 26 months' corrected age (CA) was defined as a Bayley Scales of Infant and Toddler Development, Third Edition, cognitive composite score less than 85, a motor composite score less than 85, moderate or severe cerebral palsy, gross motor function classification system score of 2 or greater, bilateral blindness, and/or hearing impairment. Data were analyzed from September 2017 to October 2018.

EXPOSURES

Birth weight less than 400 g.

MAIN OUTCOMES AND MEASURES

The primary outcome was survival to discharge among infants who received active treatment. Analysis of follow-up data was limited to infants born from 2008 to 2015 to ensure children had reached assessment age. Within this cohort, neurodevelopmental outcomes were assessed for infants who survived to 18 to 26 months' CA and returned for a comprehensive visit.

RESULTS

Of the 205 included infants, 121 (59.0%) were female, 133 (64.9%) were singletons, and 178 (86.8%) were small for gestational age. Almost half (101 of 205 [49.3%]) received active treatment at birth. A total of 26 of 205 infants (12.7%; 95% CI, 8.5-18.9) overall survived to discharge, and 26 of 101 actively treated infants (25.7%; 95% CI, 17.6-35.4) survived to discharge. Within the subset of infants with a BW less than 400 g and a GA of 22 to 23 weeks, 6 of 36 actively treated infants (17%; 95% CI, 6-33) survived to discharge. Among infants born between 2008 and 2015, 23 of 90 actively treated infants (26%; 95% CI, 17-36) survived to discharge. Two infants died after discharge, and 2 were lost to follow-up. Thus, 19 of 90 actively treated infants (21%; 95% CI, 13-31) were evaluated at 18 to 26 months' CA. Moderate or severe NDI occurred in 14 of 19 infants (74%).

CONCLUSIONS AND RELEVANCE

Infants born with a BW less than 400 g are at high risk of mortality and significant morbidity. Although 21% of infants survived to 18 to 26 months' CA with active treatment, NDI was common among survivors.

The Youngest Survivor with Gestational Age of 21⁵/₇ Weeks

The decision whether or not to resuscitate extremely low gestational age (GA) infants is recommended to be individualized according to antenatal counseling with parents, neonatologists, and obstetricians. A GA of 22⁰/₇-23⁶/₇ weeks is generally considered as the lower end of the range where infants can be candidates for selective resuscitation. Below this lower end of periviable gestation, resuscitation is usually not considered and survivors are rarely reported. To date, the youngest survivor is an infant with a GA of 21⁶/₇ weeks reported in the English medical literature. Here, we report the case of a female infant, the first twin conceived through in vitro fertilization, with a GA of 21⁵/₇ weeks, who was resuscitated initially according to strong parental wishes after antenatal counseling and is still surviving at 43 months of age with fairly good neurodevelopmental outcome.

[Changes in the outcome for infants, with birth weight under 500 grams, at our department (First Department of Obstetrics and Gynecology, Semmelweis University, Budapest)]

INTRODUCTION

The mortality and morbidity of extremely low birth weight infants (birth weight below 1000 grams) are different from low birth weight and term infants. The Centers for Disease Control statistics from the year 2009 shows that the mortality of preterm infants with a birth weight less than 500 grams is 83.4% in the United States. In many cases, serious complications can be expected in survivals.

AIM

The aim of this retrospective study was to find prognostic factors which may improve the survival of the group of extremely low birth weight infants (<500 grams).

METHOD

Data of extremely low birth weight infants with less than 500 grams born at the 1st Department of Obstetrics and Gynecology, Semmelweis University between January 1, 2006 and June 1, 2012 were analysed, and mortality and morbidity of infants between January 1, 2006 and December 31, 2008 (period I) were compared those found between January 1, 2009 and June 1, 2012 (period II). Statistical analysis was performed with probe-t, -F and -Chi-square.

RESULTS

Survival rate of extremely low birth weight infants less than 500 grams in period 1 and II was 26.31% and 55.17%, respectively (p = 0.048), whereas the prevalence of complications were not significantly different between the period examined. The mean gestational age of survived infants (25.57 weeks) was higher than the gestational age of infants who did not survive (24.18 weeks) and the difference was statistically significant (p = 0.0045).

CONCLUSIONS

Education of the team of the Neonatal Intensive Care Unit, professional routine and technical conditions may improve the survival chance of preterm infants. The use of treatment protocols, conditions of the Neonatal Intensive Care Unit and steroid prophylaxis may improve the survival rate of extremely low birth weight infants.

Survival of pre-viable preterm infants in the United States: a systematic review and meta-analysis

The objective of this paper is to review observational studies that addressed the survival of pre-viable gestations in the United States. We searched PubMed, Ovid, CINAHL, and Web of Knowledge for studies reporting survival of infants born at <24 gestational weeks and/or <500g in the United States and published between January 2003 and January 2013. The full texts of 70 articles were examined and a total of 15 studies qualified and were selected. We analyzed fixed-effect and random-effects models for eight studies on survival to discharge. Pooled survival to discharge in the random-effects model was 45.9% (95% CI: 41.1-51.7) and 39.7% in the fixed-effect model (95% CI: 38.8-40.7). Studies differed by pre-viable survival measures and epochs (1985-2009). Protective factors included antenatal corticosteroids, neonatal resuscitation, and intensive care. The current survival threshold for pre-viable infants warrants reconsideration of the limits of viability. Protective factors that enhance survival should be considered in the management of these infants.

Long-term follow-up of 2 newborns with a combined birth weight of 540 grams

Long-term growth and developmental data are presented for the smallest and third smallest surviving newborns in the world literature to 5 and 20 years of age, respectively. Both patients exhibited normal motor and language development. Although head circumference for both newborns demonstrated catchup growth, significant differences in height and weight growth velocities persisted.