Retinopathy of prematurity in assisted versus natural conception and singleton versus multiple births

Perinatal and neonatal risk factors for retinopathy of prematurity in very low birthweight, very preterm twins: a population-based study

OBJECTIVE

To determine the effect of perinatal and neonatal risk factors on retinopathy of prematurity (ROP) and to examine the association of fertility treatments on the risk for ROP in very low birth weight (VLBW) preterm twins.

METHODS

The population-based observational study consisted of VLBW twins born at 24-29 weeks gestational age (GA). Data from the Israel national database (1995-2020) were applied. Univariate and multivariable logistic regression using the General Estimating Equation were used for assessment of risk factors.

RESULTS

The study population comprised 4092 infants of whom 2374 (58%) were conceived following fertility treatments. ROP was diagnosed in 851 (20.8%) infants. The odds for ROP approximately doubled with each week decrease in GA: at 24 weeks, Odds Ratio (OR) 58.00 (95% confidence interval (CI) 31.83-105.68); 25 weeks, OR 25.88 (95% CI 16.76-39.96); 26 weeks, OR 12.69 (95% CI 8.84-18.22) compared to 29 weeks GA. Each decrease in one birthweight z-score was associated with 1.82-fold increased risk for ROP (OR, 1.82, 95% CI 1.59-2.08). Infertility treatments were not associated with ROP. Neonatal morbidities significantly associated with ROP were surgical necrotizing enterocolitis (NEC) (OR, 2.04, 95% CI 1.31-3.19); surgically treated patent ductus arteriosus (PDA) (OR, 1.63, 95% CI 1.12-2.37); sepsis (OR, 1.43, 95% CI 1.20-1.71) and bronchopulmonary dysplasia (OR, 1.52, 95% CI 1.22-1.90).

CONCLUSION

Among preterm VLBW twins, poor intrauterine growth and surgical interventions for NEC and PDA were associated with high odds for ROP. This study does not support an association of fertility treatments with increased risk for ROP.

Retrospective Comparative Analysis of Neonatal Mortality and Morbidity in Preterm Singleton and Multiple Births -Single Center Experience

Objective. To compare mortality and major neonatal morbidities between singleton preterm infants and preterm infants of multiple gestations born <33 weeks' gestation. Method. Case-control study of preterm multiples and singletons <33 weeks' born at King Abdul-Aziz Medical City Riyadh (KAMC-R) between January 2017 and December 2020. Out-born infants and infants with lethal congenital abnormalities were excluded from the study. Mortality and major neonatal morbidities including bronchopulmonary dysplasia (BPD), retinopathy of prematurity (ROP), sepsis and surgical necrotizing enterocolitis (NEC) were compared between preterm singletons and multiples. Results. A total of 803 preterm infants were included: 567 (70.6%) were singletons, 158 (19.6%) were twins and 36 (4.5%) infants were higher multiples. Adjusted mortality before hospital discharge was significantly higher among preterm infants of multiple gestations compared to preterm singletons (12.3% vs 7.9%; P = .003; AOR, 2.2; 95% CI, 1.3-3.7). Retinopathy of prematurity (ROP) needing treatment was significantly higher among preterm infants of multiple pregnancies compared to preterm singletons (11% vs 6.5%, P = .033, AOR 1.1, 95% CI, 1.04-2.99). In addition, the incidence of bronchopulmonary dysplasia (BPD) at 36 weeks post menstrual age (PMA) (29.7% vs 20.5%; P = .003; AOR, 1.7; 95% CI, 1.2-2.5) and culture positive sepsis (24.2% vs 17.5%; P = .044; AOR, 1.5; 95% CI, 1.01-2.2) were significantly higher among preterm infants of multiple pregnancy. There were no differences in mortality and adverse neonatal outcomes between twins and higher multiples. Conclusion. Preterm infants of multiple gestations suffered higher mortality and neonatal morbidities compared to preterm singleton infants despite a higher utilization of maternal antenatal steroids and better antenatal care.

Risk factors in the development of retinopathy of prematurity: A 10-year retrospective study

OBJECTIVE

To evaluate Retinopathy of Prematurity (ROP) rate and risk factors in a large cohort of preterm newborns.

METHODS

Single center retrospective study. All preterm inborn hospitalized at the Neonatal Intensive Care Unit of the Policlinico of Catania from January 1, 2009 till December 31, 2018, were included. ROP stage and location, treatments required, maternal and infant risk factors were evaluated.

RESULTS

Medical records of 898 preterms were retrospectively examined (mean gestational age 32.9 ± 2.3 weeks). Of them 149 (16.6 %) developed bilateral ROP (92 stage 1, 44 stage 2 and 13 stage 3); 66 (7.3 %) received bilateral laser treatment. Six eyes of three patients affected by zone I ROP 1, with plus persistence 15 days after an optimal laser treatment, also received intravitreal ranibizumab injection. Risk factors for ROP development were gestational age (GA) (p < 0.001), birthweight (p < 0.001), assisted ventilation duration (p < 0.001), multiple birth (p = 0.003), erythropoietin (EPO) administration (p = 0.005) and persistence of tunica vasculosa lentis. The decision-tree analysis showed gestational age as the most significant predictive factor (P < 0.001); secondary predictive factors were EPO administration (p = 0.001) in newborns 29-31 weeks GA and birthweight lower than 2090 g (p < 0.001) in 32-34 weeks GA; in this latter group patent ductus arteriosus (PDA) was a tertiary predictive factor (p = 0.043).

CONCLUSIONS

In our study ROP incidence was 16,6 %; 7.3 % of the patients required laser treatment. Besides well-known factors, such as GA and birthweight, other factors like duration of assisted ventilation, EPO, multiple births, PDA, tunica vasculosa lentis persistence should be considered to tailor ophthalmic evaluation and follow-up.

A Prospective Analysis of the Retinopathy of Prematurity Correlated with the Inflammatory Status of the Extremely Premature and Very Premature Neonates

Retinopathy of Prematurity (ROP) is a major cause of blindness in premature infants. This study aimed to evaluate the association between inflammatory markers and ROP development in extremely premature and very premature neonates and identify potential inflammatory biomarkers for ROP risk prediction. This prospective study was conducted from January 2021 to January 2023 in two clinical hospitals associated with the "Victor Babes" University of Medicine and Pharmacy Timisoara. The study population comprised neonates with a gestational age of less than 32 weeks. Various inflammatory markers, including total white blood cell count, polymorphonuclear leukocytes, C-reactive protein, interleukin-6, and lactate dehydrogenase, were analyzed from blood samples collected at birth and three days postnatally. ROP was diagnosed and classified following the International Classification of Retinopathy of Prematurity. The study included 48 neonates, 12 Extremely Premature Infants (EPI), and 36 Very Premature Infants (VPI). The EPI group had significantly higher mean interleukin-6 and lactate dehydrogenase levels at birth and three days postnatally than the VPI group. C-reactive protein levels at three days were significantly higher in the VPI group. Umbilical cord inflammation and ROP severity were found to have a statistically significant positive correlation. Half of the EPIs had moderate to severe ROP, significantly more than in the VPI group. The duration of oxygen supplementation, mechanical ventilation, Continuous Positive Airway Pressure (CPAP), gestational age less than 28 weeks, and umbilical cord inflammation at or above stage 3 were significant risk factors for developing ROP stage 2 or above. Elevated CRP and IL-6 were also significantly associated with an increased risk of developing ROP stage 2 or above, highlighting their potential as biomarkers for ROP risk prediction. This study suggests a significant association between inflammatory markers and ROP development in extremely premature and very premature neonates. These findings could contribute to the identification of potential inflammatory biomarkers for ROP risk prediction, improving early diagnosis and intervention strategies for this condition.

Perinatal characteristics and neonatal outcomes of singletons and twins in Chinese very preterm infants: a cohort study

BACKGROUND

The prevalence of preterm birth has been rising, and there is a paucity of nationwide data on the perinatal characteristics and neonatal outcomes of twin deliveries of very preterm infants (VPIs) in China. This study compared the perinatal characteristics and outcomes of singletons and twins admitted to neonatal intensive care units (NICUs) in China.

METHODS

The study population comprised all infants born before 32 weeks in the Chinese Neonatal Network (CHNN) between January 2019 and December 2019. Three-level and population-average generalized estimating equation (GEE)/alternating logistic regression (ALR) models were used to determine the association of twins with neonatal morbidities and the use of NICU resources.

RESULTS

During the study period, there were 6634 (71.2%) singletons and 2680 (28.8%) twins, with mean birth weights of 1333.70 g and 1294.63 g, respectively. Twins were significantly more likely to be delivered by caesarean section (p < 0.01), have antenatal steroid usage (p = 0.048), have been conceived by assisted reproductive technology (ART) (p < 0.01), have a higher prevalence of maternal diabetes (p < 0.01) and be inborn (p < 0.01) than singletons. In addition, twins had a lower prevalence of small for gestational age, maternal hypertension, and primigravida mothers than singletons (all p < 0.01). After adjusting for potential confounders, twins had higher mortality rates (adjusted odds ratio [AOR] 1.28, 95% confidence interval [CI] 1.10-1.49), higher incidences of short-term composite outcomes (AOR 1.28, 95% CI 1.09-1.50), respiratory distress syndrome (RDS) (AOR 1.30, 95% CI 1.12-1.50), and bronchopulmonary dysplasia (BPD) (AOR 1.10, 95% CI 1.01-1.21), more surfactant usage (AOR 1.22, 95% CI 1.05-1.41) and prolonged hospital stays (adjusted mean ratio 1.03, 95% CI 1.00-1.06), compared to singletons.

CONCLUSION

Our work suggests that twins have a greater risk of mortality, a higher incidence of RDS and BPD, more surfactant usage, and longer NICU stays than singletons among VPIs in China.

Retrospective validation of G-ROP, CO-ROP, Alex-ROP, and ROPscore predictive algorithms in two Chinese medical centers

Purpose

To evaluate the sensitivity and specificity of four predictive algorithms (G-ROP, CO-ROP, Alex-ROP, and ROPscore) for retinopathy of prematurity and compare their performances in the Chinese population.

Methods

A retrospective study was conducted at two medical centers in China of infants born at Women's Hospital School of Medicine Zhejiang University and Yiwu Maternal and Child Health Hospital. A total of 1,634 infants who met the criteria and who were GA < 32 weeks or BW < 2,000 g according to Chinese guidelines for ROP screening were included. The ROP group was further grouped into severe ROP and mild ROP. The sensitivity and specificity of G-ROP, two simplified G-ROPs, CO-ROP, Alex-ROP, and ROPscore were analyzed.

Results

Severe ROP and any ROP were identified in 25 and 399 of 1,634 infants, respectively. According to the criteria of different models, 844, 1,122, 1,122, and 587 infants were eligible in the G-ROP, CO-ROP, Alex-ROP, and ROPscore, respectively. G-ROP had 96.0% sensitivity and 35.0% specificity for severe ROP. For two simplified G-ROPs (180 g and 200 g models), similar sensitivity was showed with original G-ROP and they had specificity of 21.8% and 14.0%, respectively. The sensitivity and specificity of Co-ROP were 96% and 64.3% for severe ROP, while Alex-ROP only had sensitivity of 56.0% and specificity of 61.4% for severe ROP. ROPscore had a sensitivity of 91.3% and a specificity of 62.4% for severe ROP. In 546 infants who met all 4 models' inclusion criteria and included 23 infants with severe ROP, the validation outcomes showed the sensitivity of G-ROP, ROPscore, CO-ROP, and Alex-ROP for severe ROP was 95.6%, 91.3%, 100%, and 56.0%, and their specificity was 38.0%, 60.8%, 39.9%, and 52.9%, respectively.

Conclusion

G-ROP, ROPscore, and CO-ROP had high sensitivity for severe ROP in the Chinese population, but both the sensitivity and specificity of Alex-ROP were low. CO-ROP (not high-grade CO-ROP) provided the best performance for severe ROP in a fair comparison. For further application, ROP screening models need to be adjusted by local populations.

Treatment for Retinopathy of Prematurity in Twins: The Small Twin without High Birth Weight Discordant Is Not at Increased Risk

Purpose: As common retinopathy is observed in low-birth infants, the characteristics of ROP in twins are worth exploring. The present study tried to demonstrate the risk factors of treatment for retinopathy of prematurity (ROP) in twins both diagnosed with ROP. Methods: A retrospective, institution-based cohort study of 62 premature ROP twin pairs with a mean gestational age (GA) younger than 35 weeks and a birth weight (BW) lower than 2500 g. Only infants with a follow-up period longer than 6 months and complete treatment records were included. The demographic data, treatment requirements and further rescue treatments were all collected and analyzed for all infants according to whether they accepted treatments. Moreover, all twin infants were divided into small and large twin groups according to birth weight, and they were also categorized as three groups according to the treatment requirement including both twins receiving treatment (BT group), one of the twins receiving treatment (ST group) and none of the twins receiving treatment (NT group). Comparisons of demographic data, treatment requirements and further rescue treatments were all conducted according to the different grouping methods. Results: The mean GA of the enrolled infants was (29.29 ± 2.45) weeks with a mean BW of (1335.77 ± 390.36) grams. Among them, 110 infants were mechanically ventilated. Fifty-one of the infants did not receive any treatment and 73 infants received laser or intravitreal injection of anti-VEGF agents. In total, 64 infants only underwent intravitreal injection of anti-VEGF agents or laser treatment, while the other nine infants received scleral buckling or vitrectomy as a necessary treatment when the retinal detachment was observed. No significantly different mechanical ventilation or treatment requirements could be observed between the small twin group and the large twin group (p = 0.73, 0.94). The twins in the BT groups showed the lowest BW, while the NT group infants had the highest BW. The GA for the BT, ST and NT groups were (27.86 ± 1.87) weeks, (29.60 ± 1.52) weeks and (31.33 ± 2.39) weeks, respectively, and showed significant differences as well (p < 0.001). Conclusion: Being a small twin in twin-paired ROP without a high BW discordant will not increase the risk for treatment requirement or additional surgery necessity with a much more severe stage of ROP.

Demographic Risk Factors of Retinopathy of Prematurity: A Systematic Review of Population-Based Studies

INTRODUCTION

Current national guidelines use gestational age (GA) and birth weight (BW) as their basis for retinopathy of prematurity (ROP) screening. The strength of association of these and other demographic risk factors is inconsistent across studies. This review aims to evaluate the strength of association of documented risk factors for ROP in large sample, population-based studies.

METHODS

MEDLINE, EMBASE, and Cochrane Library were searched from January 2010 to May 2020. Original studies reporting the risk of ROP in a region and demographic risk factors were included.

RESULTS

Eighteen studies comprising 342,005 infants were included. The overall risk of ROP in preterm infants was 18.8%. For every week decrease in GA, there was a median adjusted odds ratio (aOR) of 1.4 times (range 1.2-1.9) of developing ROP. For every 100-g decrease in BW, the median aOR was 1.8 times (range 1.2-2.7). Higher risk was found in infants with neonatal sepsis and bronchopulmonary dysplasia. The risk of any, severe, and treatment-requiring ROP was highest for 23 weeks GA, which was 66.5, 40.3, and 39.4%, respectively. Regions with higher neonatal mortality rates had the highest mean GA of infants with ROP.

CONCLUSION

For every week decrease in GA and every 100-g decrease in BW, there was a median of 1.4 times and 1.8 times the odds of developing ROP, respectively. Further research is required to clarify the role of additional risk factors.

Ductus Arteriosus of Extremely Preterm Twins is More Resistant to Cyclooxygenase Inhibitors Than Those of Singletons

Symptomatic patent ductus arteriosus (sPDA) is common among preterm infants, and can lead to several complications. This is particularly true for extremely preterm infants, as closure of the ductus arteriosus using cyclooxygenase inhibitors is often difficult. A recent study using a preterm sheep model showed that intimal thickening-required for anatomical closure of the ductus arteriosus-is less developed in twins than in singletons. Therefore, this study primarily aimed to prove that the ductus arteriosus of extremely preterm twins is more resistant to cyclooxygenase inhibitors than those of extremely preterm singletons. Its secondary aim was to assess whether the resistance against cyclooxygenase inhibitors differed according to chorionicity. In this retrospective case-control study, medical records of 162 extremely preterm infants (gestational age < 28 weeks) were reviewed, and the treatment course of sPDA was subsequently compared between singletons (n = 131) and twins (n = 31). The median indomethacin doses for sPDA and the necessity for surgical ligation were significantly higher in twins than in singletons (5 vs 2 [p < 0.001] and 42% vs 21% [p = 0.018], respectively). No significant differences in sPDA treatment, including the number of indomethacin doses and the necessity for surgical ligation, were observed between monochorionic diamniotic and dichorionic diamniotic twins. This study confirms that the ductus arteriosus of extremely preterm twins is more resistant to cyclooxygenase inhibitors than those of singletons. However, there was no significant difference in sPDA treatment by chorionicity.

Outcomes of multiple gestation births compared to singleton: analysis of multicenter KID database

Background

The available data regarding morbidity and mortality associated with multiple gestation births is conflicting and contradicting.

Objective

To compare morbidity, mortality, and length of stay (LOS) outcomes between multiple gestation (twin, triplet and higher-order) and singleton births.

Methods

Data from the national multicenter Kids’ Inpatient Database of the Healthcare Cost and Utilization Project from the years 2000, 2003, 2006, 2009, 2012, and 2016 were analyzed using a complex survey design using Statistical Analysis System (SAS) 9.4 (SAS Institute, Cary NC). Neonates with ICD9 and ICD10 codes indicating singletons, twins or triplets, and higher-order multiples were included. Mortality was compared between these groups after excluding transfer outs to avoid duplicate inclusion. To analyze LOS, we included inborn neonates and excluded transfers; who died inpatient and any neonates who appear to have been discharged less than 33 weeks PMA. The LOS was compared by gestational age groups.

Results

A total of 22,853,125 neonates were analyzed for mortality after applying inclusion-exclusion criteria; 2.96% were twins, and 0.13% were triplets or more. A total of 22,690,082 neonates were analyzed for LOS. Mean GA, expressed as mean (SD), for singleton, twins and triplets, were 38.30 (2.21), 36.39 (4.21), and 32.72 (4.14), respectively. The adjusted odds for mortality were similar for twin births compared to singleton (aOR: 1.004, 95% CI:0.960–1.051, p = 0.8521). The adjusted odds of mortality for triplet or higher-order gestation births were higher (aOR: 1.33, 95% CI: 1.128–1.575, p = 0.0008) when compared to the singleton births. Median LOS (days) was significantly longer in multiple gestation compared to singleton births overall (singletons: 1.59 [1.13, 2.19] vs. twins 3.29 [2.17, 9.59] vs. triplets or higher-order multiples 19.15 [8.80, 36.38], p < .0001), and this difference remained significant within each GA category.

Conclusion

Multiple gestation births have higher mortality and longer LOS when compared to singleton births. This population data from multiple centers across the country could be useful in counseling parents when caring for multiple gestation pregnancies.

Supplementary Information

The online version contains supplementary material available at 10.1186/s40748-021-00135-5.

Risk Factors Associated with Retinopathy of Prematurity in Very and Extremely Preterm Infants

Background and Objectives: Retinopathy of prematurity (ROP) is the leading cause of blindness in preterm infants. We studied the relationship between different perinatal characteristics, i.e., sex; gestational age (GA); birth weight (BW); C-reactive protein (CRP) and lactate dehydrogenase (LDH) concentrations; ventilation, continuous positive airway pressure (CPAP), and surfactant administration; and the incidence of Stage 1–3 ROP. Materials and Methods: This study included 247 preterm infants with gestational age (GA) < 32 weeks that were successfully screened for ROP. Univariate and multivariate binary analyses were performed to find the most significant risk factors for ROP (Stage 1–3), while multivariate multinomial analysis was used to find the most significant risk factors for specific ROP stages, i.e., Stage 1, 2, and 3. Results: The incidence of ROP (Stage 1–3) was 66.40% (164 infants), while that of Stage 1, 2, and 3 ROP was 15.38% (38 infants), 27.53% (68 infants), and 23.48% (58 infants), respectively. Following univariate analysis, multiple perinatal characteristics, i.e., GA; BW; and ventilation, CPAP, and surfactant administration, were found to be statistically significant risk factors for ROP (p < 0.001). However, in a multivariate model using the same characteristics, only BW and ventilation were significant ROP predictors (p < 0.001 and p < 0.05, respectively). Multivariate multinomial analysis revealed that BW was only significantly correlated with Stage 2 and 3 ROP (p < 0.05 and p < 0.001, respectively), while ventilation was only significantly correlated with Stage 2 ROP (p < 0.05). Conclusions: The results indicate that GA; BW; and the use of ventilation, CPAP, and surfactant were all significant risk factors for ROP (Stage 1–3), but only BW and ventilation were significantly correlated with ROP and specific stages of the disease, namely Stage 2 and 3 ROP and Stage 2 ROP, respectively, in multivariate models.

POTENTIAL UTILITY OF FOVEAL MORPHOLOGY IN PRETERM INFANTS MEASURED USING HAND-HELD OPTICAL COHERENCE TOMOGRAPHY IN RETINOPATHY OF PREMATURITY SCREENING

PURPOSE

To investigate dynamic foveal morphology with postmenstrual age, in preterm infants with and without retinopathy of prematurity using hand-held optical coherence tomography, adjusting for gestational age (GA) and birthweight (BW).

METHODS

Prospective mixed cross-sectional/longitudinal observational study of 87 participants (23-36 weeks GA; n = 30 with, n = 57 without retinopathy of prematurity) using hand-held optical coherence tomography images (n = 278) acquired between 31 weeks and 44 weeks postmenstrual age excluding treated retinopathy of prematurity. Measurements included foveal width, area, depth, central foveal thickness, maximum slope, and parafoveal retinal thickness at 1,000 µm nasal and temporal to the central fovea.

RESULTS

Retinopathy of prematurity was significantly correlated with only foveal width in either GA or BW adjusted statistical models. In contrast, severity of prematurity (GA, BW) correlated with foveal area (P < 0.005), depth (P ≤ 0.001), and slope (P < 0.01), although central foveal thickness (P = 0.007) and parafoveal retinal thickness (P < 0.001) correlated with GA, but not with BW.

CONCLUSION

Foveal width is independent of GA and BW with potential in retinopathy of prematurity screening assessment using hand-held optical coherence tomography. Foveal morphology could be graded in prematurity during development, with possible implications for future management of preterm infants.

Population based retrospective cohort study on risk of retinopathy of prematurity in twins

Background

Twin infants are likely at great risk for ROP, but studies reported conflicting findings and population studies examining the risk of retinopathy of prematurity (ROP) in twins is limited. We aimed to evaluate the ROP risk in the cohort of one of twins, comparing to singletons.

Material and methods

Using insurance claims data of a half of children in Taiwan ages 18 and less, we established a twin cohort (N = 27830) born in 1998–2009 and a randomly selected singleton cohort (N = 111080) frequency matched by sex, birth year, residential area and parental occupation and followed up to 2012 years.

Results

The overall incidence rate of ROP was 13.6-fold greater in the twin cohort than in the singleton cohort (35.1 vs. 2.58 per 10,000 person-years; adjusted HR = 13.4, 95% CI = 11.7–15.3; p <0.0001). The ROP incidence was slightly higher in boys than in girls, higher in children in more urbanized areas and born to mothers without works. The incident ROP increased with decreasing birthweight. For children with birthweight <1000 grams, the ROP incidence was 1.2-fold greater in the twin cohort than in the singleton cohort (1243.2 vs. 1016.3 per 10,000 person-years). The use of mechanical ventilation was associated with increased ROP risk for both cohorts, particularly for infants who were under invasive treatment.

Conclusion

Infants who were born as twins or born with low birthweight were at an elevated risk of developing ROP. Extreme cautious and close monitor are required for new born with low birthweight and have undergone with mechanical ventilation.

The Risk of Retinopathy of Prematurity in the Infants following Assisted Reproductive Technology: A Meta-Analysis

Currently, the use of assisted reproductive technology (ART) is increasing. Because of the poor prognosis of retinopathy of prematurity (ROP), the association between ART and the ROP has been explored in several studies, but the result was still inconclusive. Conducting a meta-analysis, we evaluated the risk of ROP in relation to the ART. Subgroup analysis as well as groups with different embryo numbers and different ROP stages was further analyzed. The PubMed, Embase, and Cochrane Library databases were searched for studies recording data about both the use of ART and ROP occurrence simultaneously. Odds ratios (ORs) and 95% confidence interval (95%CI) were calculated to analyze the association by using random- or fixed-effect models based on heterogeneity test. In total 15 observational studies containing 10392 ART cases and 39474 spontaneous conception cases were included. Results showed that there was a significant association between the use of ART and ROP occurrence in the offspring (OR = 1.34, 95% CI: 1.05 to 1.73, P = 0.02). With subgroup analysis, we found that the influence actually came from a subgroup of ART, the in vitro fertilization (IVF). Moreover, there was a significant association between ART and ROP in singletons. Though insignificant, the ORs were larger than 1 in the analysis between ART and stage 1 and 2 ROP. But ART showed significant association with stage 3 ROP. Our study preliminarily indicated that the use of IVF was associated with higher risk of ROP occurrence. And ART is more likely to result in severe ROP and ROP in singletons. Further specific, high-quality studies with large sample size are still needed to draw more precise conclusion.

Artificial Reproductive Technology - A Risk Factor for Retinopathy of Prematurity

BACKGROUND:

Retinopathy of Prematurity (ROP) is a potentially blinding vasoproliferative disease in premature babies. The presentation and course of ROP are determined by a complex interaction of a series of risk factors, including artificial reproductive technology (ART).

AIM:

To analyse and combine the information relating ART as an independent risk factor for retinopathy of prematurity.

METHODS AND MATERIAL:

The article is systematic review and meta-analysis using RevMan 5. Pubmed, Scopus and Medline were searched for articles from 1990 to 2018.

RESULTS:

Studies suggest that ROP is observed more frequently in ART children. They are more likely to be premature and of low birth weight than those conceived naturally. Results vary from just a tendency to a five-fold increase in risk to develop ROP in ART babies. At the same time, they might develop ROP later, and more mature newborns might be affected.

CONCLUSION:

The data relating ART as a risk factor for ROP is inconclusive, but most studies show at least a tendency. The ART newborns need to be considered as a risk group for ROP and observed with greater suspicion. Even more mature ART newborns might need to be screened in order not to miss any significant pathology.

Retinopathy of prematurity: a review of risk factors and their clinical significance

Retinopathy of prematurity (ROP) is a retinal vasoproliferative disease that affects premature infants. Despite improvements in neonatal care and management guidelines, ROP remains a leading cause of childhood blindness worldwide. Current screening guidelines are primarily based on two risk factors: birth weight and gestational age; however, many investigators have suggested other risk factors, including maternal factors, prenatal and perinatal factors, demographics, medical interventions, comorbidities of prematurity, nutrition, and genetic factors. We review the existing literature addressing various possible ROP risk factors. Although there have been contradictory reports, and the risk may vary between different populations, understanding ROP risk factors is essential to develop predictive models, to gain insights into pathophysiology of retinal vascular diseases and diseases of prematurity, and to determine future directions in management of and research in ROP.

Is artificial reproductive technology a risk factor for retinopathy of prematurity independent of the generation of multiple births?

PURPOSE

There is some debate regarding whether artificial reproductive technology (ART) constitutes an independent risk factor for retinopathy of prematurity (ROP). We wanted to assess the prevalence of ART in multiple birth infants seen for ROP screening and whether or not ROP was identified or treated, in order to evaluate whether ART contributes a risk factor for ROP independent of the generation of multiple births.

METHODS

A retrospective audit was performed of all multiple birth babies admitted to a tertiary neonatal unit who met the UK ROP screening criteria (<32 weeks gestational age [GA] and/or <1,501 g birthweight [BW]).

RESULTS

A total of 205 babies met our criteria, of whom 87.3% were twins. A total of 39.5% were born following ART. A total of 30.5% of the non-ART group developed ROP vs 34% of the ART group (p = 0.837). Stage 3 ROP developed in 5.1% of non-ART babies and 6% of ART babies. A total of 8.5% of non-ART babies and 10% of ART babies required treatment for ROP. Logistic regression demonstrated that ART was not independently associated with development of ROP.

CONCLUSIONS

Artificial reproductive technology multiple birth babies make up a considerable proportion of the ROP screening burden and their number is likely to increase as ART is increasingly available and utilized. We found no significant difference between the numbers of babies developing ROP in the ART vs non-ART groups, but the numbers are small. The estimated odds of developing ROP are slightly higher in the ART babies, so our data do not rule out a possible association.

Retinopathy of Prematurity in Triplets

OBJECTIVES

To investigate the incidence, severity and risk factors of retinopathy of prematurity (ROP) in triplets.

MATERIALS AND METHODS

The medical records of consecutive premature triplets who had been screened for ROP in a single maternity hospital were analyzed and presence and severity of ROP; birth weight, gender, gestational age of the infant; route of delivery and the mode of conception were recorded.

RESULTS

A total of 54 triplets (40 males, 14 females) who were screened for ROP between March 2010 and February 2013 were recruited for the study. All triplets were delivered by Caesarean section and 36 (66.7%) were born following an assisted conception. During follow-up, seven (13%) of the infants developed ROP of any stage and two (3.7%) required laser photocoagulation. The mean gestational age of triplets with ROP was 27.6±1.5 (27-31) weeks whereas it was 32.0±1.5 (30-34) weeks in those without ROP (p=0.002). The mean birth weights of triplets with and without ROP were 1290.0±295.2 (970-1600) g and 1667.5±222.2 (1130-1960) g, respectively (p<0.001). The presence of ROP was not associated with gender (p=0.358) or mode of conception (p=0.674).

CONCLUSION

ROP in triplets seems to be mainly related to low gestational age and low birth weight. Further prospective randomized studies are necessary to demonstrate risk factors of ROP in triplets and to determine if and how gemelarity plays a role in the development of ROP.

Perinatal outcome comparing triplets and singleton births at a reference maternity hospital

OBJECTIVE

The objective of the present study was to evaluate adverse perinatal outcome in a group of high order pregnancies pared with singletons by BW and GA at birth.

METHODS

Data was reviewed for all admissions of triplets and quadruplets in a 7 year period. For each study neonate we selected two singleton infants to constitute a control group. Variables analyzed included: respiratory distress syndrome, patent ductus arteriosus, intraventricular hemorrhage, necrotizing enterocolitis (NEC), bronchopulmonary dysplasia, retinopathy of prematurity and periventricular leukomalacia.

RESULTS

We studied a total of 128 multiple and 260 singleton infants. Mean gestational age and birth weight were similar in both groups (31.3 ± 2,5 wks e 31.5 ± 2,8 wks; 1470 ± 461 g vs 1495 ± 540 g). There was no significant difference between the groups in the majority of main morbidities. The incidence of NEC was higher in triplets (6.3 vs 0.8%, p value <0.01). Mortality was higher in singletons (9.6 vs 3.1%, p value <0.037).

CONCLUSIONS

Results show that major neonatal outcomes are very similar between multiples and singletons births when paired by gestational age and birth weight. NEC remained a significant morbidity in infants born from multiple gestations after adjustment for maternal and neonatal risk factors.

Incidence and Risk Factors of Retinopathy of Prematurity From 2 Neonatal Intensive Care Units in a Hong Kong Chinese Population

PURPOSE

To determine the incidence and risk factors of retinopathy of prematurity (ROP) in very low birth weight (VLBW) preterm Chinese infants.

DESIGN

Retrospective review.

METHODS

Medical records were reviewed for all neonates screened for ROP between January 2007 and December 2012 in Hong Kong. Screening was offered to VLBW (≤1500 g) and/or preterm (gestation, ≤32 weeks) neonates using the Royal College of Ophthalmologists ROP guideline and the International Classification of ROP by 3 pediatric ophthalmologists. Maternal and neonatal covariates were analyzed using univariate and multivariable logistic regression analyses for both ROP and type 1 ROP.

RESULTS

Of the 513 screened infants, the mean gestational age (GA) was 30.0 ± 2.5 weeks and the mean birth weight (BW) was 1232.6 ± 325.2 g. The incidence of ROP and type 1 ROP was 18.5% and 3.7%, respectively. In univariate analysis, a lighter BW, lower GA, blood transfusion, patent ductus arteriosus, nonsteroidal anti-inflammatory drug use, postnatal hypotension, inotropes usage, low Apgar scores, sepsis, mechanical ventilation, supplementary oxygen use, respiratory distress syndrome, anemia, surfactant use, and bronchopulmonary dysplasia were found to be associated with the development of both ROP and type 1 ROP (P < 0.05). In multivariable logistic regression analysis, BW, GA, and intraventricular hemorrhage were significant risk factors for ROP. Preeclampsia and eclampsia were the only protective factors for ROP development on multivariable logistic regression analysis (P = 0.02).

CONCLUSIONS

In VLBW preterm Chinese infants, lower GA, lighter BW, and intraventricular hemorrhage were significant risk factors for ROP, whereas preeclampsia and eclampsia were protective.

Incidence and risk factors for retinopathy of prematurity in multiple gestations: a Chinese population study

To determine the incidence and risk factors of retinopathy of prematurity (ROP) among new-born Chinese infants of multiple gestations.A retrospective review of medical records was performed for all neonates of multiple gestations screened for ROP between January 2007 and December 2012 in 2 neonatal intensive care units in Hong Kong. Screening was offered to very low birth weight (VLBW; ≤1500 g) and/or preterm (gestation ≤32 weeks) neonates using the Royal College of Ophthalmologists ROP guideline and the International Classification of ROP by 3 pediatric ophthalmologists. Maternal and neonatal covariates were analyzed using univariate and multivariate regression analyses for both ROP and Type 1 ROP.A total of 153 Chinese infants of multiple gestations were included in the study. The mean gestational age (GA) was 30.8 ± 2.4 weeks and the mean birth weight (BW) was 1284.8 ± 267.4 g. The incidence of ROP and Type 1 ROP was 11.8% and 3.9%, respectively. On univariate analysis, younger GA, lighter birth weight, postnatal hypotension, inotropes use, bronchopulmonary disease, and intraventricular hemorrhage were common independent risk factors for the development of ROP and Type 1 ROP (all P ≤ 0.04). On multivariate analysis, younger GA, surfactant use, invasive mechanical ventilation, higher mean oxygen concentration, thrombocytopenia, intraventricular hemorrhage, total parental nutrition, and hypoglycemia were significant risk factors for ROP. For Type 1 ROP, there were no significant dependent risk factors.In preterm Chinese infants born from multiple gestations, prematurity, lighter weight, postnatal hypotension, inotropes use, bronchopulmonary dysplasia, and an intraventricular hemorrhage were common independent risk factors for the development of ROP and Type 1 ROP.

Aggressive posterior retinopathy of prematurity in two of the triplets: a case report

Aggressive posterior retinopathy of prematurity is identified as a rare, rapidly progressing and severe form of retinopathy of prematurity (ROP). Here, we report the diagnosis and treatment of aggressive posterior retinopathy of prematurity (APROP) in two of the triplets born at low birth weight and small gestational age. A case concerning two triplets who were born at 31 weeks' gestational age with low birth weight and reached bilateral threshold APROP was reported. The ROP of triplets A and B had the characteristic features of aggressive diseases, which were posterior location, prominence of plus disease and rapid progression. Low birth weight and small gestational age, multiple pregnancies, pregnancy-induced hypertension and older age of the mother might account for the presentations of APROP. These cases demonstrate the importance of early screening and diagnosis in APROP infants. Prompt and adequate laser photocoagulation with a large number of high-intensity closely performed spots and early retreatment could be effective and safe for preventing the progression of APROP with plus disease in zone 1 or 2 in premature triplets.

Severe retinopathy of prematurity with retinal detachment in monozygotic twins

We report a monochorionic diamniotic twin pair born at 29 weeks of gestation in which both twins developed severe retinopathy of prematurity (ROP) with retinal detachment. The pregnancy was terminated due to reversal of donor-recipient phenotypes in possible TTTS. Both twins had unstable cardiopulmonary status during the first week, and developed chronic lung disease. The larger twin, born at 1372 g, developed stage 4a ROP in both eyes, and the smaller twin, born at 1168 g, developed stage 4a ROP in the left eye. Genetic analysis of NDP, FZD4, LRP5, TSPAN12 genes revealed no mutations; however, VEGF gene polymorphism analysis showed heterozygous carrier state of the VEGF 936T allele in both twins, which is a risk factor for threshold ROP in Japanese newborn infants. We speculate the synergistic effects of unstable perinatal cardiopulmonary status and genetic predisposition due to VEGF 936C>T polymorphism caused the development of severe ROP with retinal detachment.

Analysis of risk factors for retinopathy of prematurity

AIM

To analyze the incidence and risk factors for retinopathy of prematurity (ROP).

METHODS

A retrospective analysis was conducted on 568 premature infants from September 2005 to December 2010 with birth weight(BW) equal to or less than 2 500g or a gestational age(GA) at birth of 34 weeks or less. All of the members were examined by indirect binocular ophthalmoscopy.

RESULTS

ROP occurred with an incidence rate of 10.7% among 568 premature infants, and stages 3 and above ROP occurred with an incidence rate of 2.5%. This study showed the infants were more prone to develop ROP with short geststional age, low BW, long time of oxygen inhalation, and severe infants diseases. Twins had a significantly higher rate of ROP(18.3%) than singleton babies(9.8%), ROP were severer in twins than singleton babies.

CONCLUSION

Short GA, low BW, long time of oxygen inhalation, severe infants diseases, and non-singleton babies were the most significant risk factors associated with ROP.

Effects of maternal and placental inflammation on retinopathy of prematurity

PURPOSE

To identify maternal and placental risk factors for the occurrence and progression of retinopathy of prematurity (ROP).

METHODS

This was a retrospective cohort study. The study cohort consisted of 246 infants with gestational age ≤ 32 weeks, with histologic examinations of their placentas. Medical records of eligible preterm infants were retrospectively reviewed. A regression model was constructed with control for known or potential factors associated with ROP. Occurrences of ROP, severe ROP (≥ stage 3), and clinically significant ROP requiring laser treatment were assessed.

RESULTS

ROP was diagnosed in 82 of 246 infants (33.3%), including 49 with mild ROP and 33 with severe ROP. Laser treatment was performed on 27 infants (11%: 27/246). Multivariate regression analysis indicated clinical chorioamnionitis and elevated maternal WBC count on admission to be associated with ROP occurrence [odds ratio (OR) = 4.370, P = 0.046; and OR = 1.104 per 1,000 cells/mm(3) incremental increase, P = 0.019, respectively], while the use of tocolytics was associated with reduced occurrence of ROP (OR = 0.278, P = 0.006). Elevated maternal WBC count on admission was also independently associated with ROP progression requiring laser treatment (OR = 1.171 per 1,000 cells/mm(3) incremental increase, P = 0.026). However, neither histologic chorioamnionitis nor funisitis was associated with the occurrence or progression of ROP.

CONCLUSIONS

Clinical chorioamnionitis and elevated maternal WBC count, but not histologic chorioamnionitis, were significantly and independently associated with ROP. These findings support the hypothesis that maternal systemic inflammation may play a role in the pathogenesis of ROP.

Association between assisted reproductive technology and advanced retinopathy of prematurity

Purpose

To investigate the associations between assisted reproductive technology (ART) and severe retinopathy of prematurity (ROP) requiring treatment.

Methods

Retrospective analyses of inborn preterm infants screened for severe ROP at the Weill Cornell Medical Center Neonatal Intensive Care Unit at the New York-Presbyterian Hospital by single factor logistic regression and multifactor models.

Results

Of 399 ethnically diverse infants, 253 were conceived naturally and 146 by ART. Eight (3.16%) patients conceived naturally, and 11 (7.53%) with ART required laser treatment. In multifactor analyses, significant risks for severe ROP requiring treatment included both gestational age (odds ratio [OR] 0.34; 95% confidence interval [CI] 0.23–0.52; P < 0.001) and ART ([OR] 4.70; [CI], 1.52–4.57; P = 0.007).

Conclusions

ART is associated with severe ROP requiring treatment in this cohort. This is the first report that demonstrates a statistically significant association between ART and severe ROP requiring treatment in infants in the US.

Heritability of apnea of prematurity: a retrospective twin study

BACKGROUND

Apnea of prematurity (AOP) is a disturbance in respiratory rhythm defined by idiopathic pauses in breathing that reduce blood oxygen levels and/or heart rate. It is a major clinical problem among preterm infants.

OBJECTIVES

The primary goal of this study was to estimate the genetic susceptibility to AOP in a cohort of preterm twins. A secondary aim was to identify risk factors associated with AOP in this cohort.

METHODS

A single-center, retrospective study (2000-2008) was performed by using data from 317 premature twin pairs (<36 weeks' gestational age). Heritability estimates were determined by comparing intrapair AOP concordance between 56 monozygotic and 161 dizygotic twin pairs by using structural equation modeling. Risk factors of AOP among a cohort of 543 premature twins were assessed by using mixed-effects logistic regression.

RESULTS

The heritability of AOP was 87% (95% confidence interval [CI]: 0.64-0.97) among same-gender twins. A gender-dependent model revealed that genetic factors accounted for 99% of the variance in male twins (95% CI: 0.89-1.00) and 78% of the variance in female twins (95% CI: 0.49-0.94). Significant risk factors for AOP were low gestational age (P<.001), cesarean delivery (P=.017), and conception through assisted reproductive technologies (P=.008).

CONCLUSIONS

These findings suggest that AOP has an important genetic basis underlying this developmental-related disorder of respiratory control. Future genomic studies may provide information on pathophysiological mechanisms that underlie AOP.

Inhibitory effects of maternal smoking on the development of severe retinopathy of prematurity

PURPOSE

In this study, the effects of maternal smoking along with other clinical risk factors in developing severe retinopathy of prematurity (ROP) were evaluated.

DESIGN

A case-control study.

METHODS

Records of newborn infants with an estimated postmenstrual age of 32 weeks or less (n=86) were reviewed. ROP grading was evaluated in accordance with the International Classification of Retinopathy of Prematurity. Severe ROP was diagnosed when it progressed to stage 3 with plus disease. The factors were first evaluated using a univariate logistic regression analysis between the groups of severe and non-severe ROP, followed by a multivariate logistic regression analysis using STATA version 10 and R version 2.71.

RESULTS

A low birth weight, a long duration of artificial ventilation and oxygen supplementation, presence of chronic lung disease, and absence of maternal smoking were found to be significantly associated with severe ROP in the univariate logistic regression analysis. In the multivariate logistic regression analysis, maternal smoking was revealed as a significant factor independently associated with the incidence of severe ROP.

CONCLUSIONS

An inhibitory effect of maternal smoking against developing severe ROP is suggested. The mechanism by which smoking may reduce the incidence of severe ROP needs to be further investigated.

Retinopathy of prematurity in twin-twin transfusion syndrome

The authors present the first reported case of retinopathy of prematurity in twin-twin transfusion syndrome. A 31-year-old woman gave birth to twins at 31 weeks' gestation. The pregnancy had been complicated by twin-twin transfusion syndrome and had been managed with two amnioreductions and laser ablation of the interplacental blood vessels. The donor twin, born at 1,310 g, had threshold retinopathy of prematurity and underwent argon laser retinal photocoagulation treatment. The recipient twin (1,775 g) did not show any evidence of retinopathy of prematurity.