[Arguments for an infectious cause of IUGR]

A systematic review on estimating population attributable fraction for risk factors for small-for-gestational-age births in 81 low- and middle-income countries

Background

Small for gestational age (SGA) is a public health concern since it is associated with mortality in neonatal and post-neonatal period. Despite the large magnitude of the problem, little is known about the population-attributable risk (PAR) of various risk factors for SGA. This study estimated the relative contribution of risk factors for SGA, as a basis for identifying priority areas for developing and/or implementing interventions to reduce the incidence of SGA births and related mortality and morbidity.

Methods

We conducted a literature review on 63 potential risk factors for SGA to quantify the risk relationship and estimate the prevalence of risk factors (RFs). We calculated the population-attributable fraction for each of the identified RF for 81 Countdown countries and calculated regional estimates. Twenty-five RFs were included in the final model while extended model included all the 25 RFs from the final model and two additional RFs.

Results

In the final and extended models, the RFs included in each model have a total PAF equal to 63.97% and 69.66%, respectively of SGA across the 81 LMICs. In the extended model, maternal nutritional status has the greatest PAF (28.15%), followed by environmental and other exposures during pregnancy (15.82%), pregnancy history (11.01%), and general health issues or morbidity (10.34%). The RFs included in the final and extended model for Sub-Saharan African (SSA) region have a total PAF of 63.28% and 65.72% of SGA, respectively. In SSA, the top three RF categories in the extended model are nutrition (25.05%), environment and other exposure (13.01%), and general health issues or morbidity (10.72%), while in South-Asia's it was nutrition (30.56%), environment and other exposure (15.27%) and pregnancy history (11.68%).

Conclusions

The various types of RFs that play a role in SGA births highlight the importance of a multifaceted approach to tackle SGA. Depending on the types of RFs, intervention should be strategically targeted at either individual or household and/or community or policy level. There is also a need to research the mechanisms by which some of the RFs might hinder fetal growth.

Late-onset intrauterine growth restriction and HHV-6 infection: A pilot study

Late-onset Intrauterine growth restriction (IUGR) refers to impaired growth and development of the fetus, characterized by placental morphological abnormalities that affect the fetus's supply of nutrients. Human leukocyte antigen-G (HLA-G) is physiologically expressed during pregnancy, but decreased in normal placenta during the last weeks of gestation possibly inducing childbirth. Several viruses involved in congenital infection, such as herpesviruses, exploit HLA-G expression as an immune-escape mechanism. To date, despite different congenital herpetic infections having been associated with late IUGR, no direct implication of Human herpesvirus 6 (HHV-6) infection has been reported. We evaluated HLA-G expression and HHV-6 infection in 11 placentas from late-onset IUGR newborns and 11 placentas from uncomplicated pregnancies by histopathological and immunohistochemistry analysis. We found higher levels of HLA-G expression and HHV-6 presence in IUGR placenta samples compared with control placenta samples. We report HHV-6 staining in IUGR placenta samples, characterized by high HLA-G expression. These preliminary data suggest a possible involvement of HHV-6 infection in HLA-G deregulation that might affect vessel remodeling and prevent the correct pregnancy outcome in the IUGR condition.

[Management of fetal growth restriction in France: Survey of teaching hospitals and tertiary referral centers]

OBJECTIVES

French Guidelines on Fetal Growth Restriction (FGR) were published in December 2013. It seemed interesting to us to carry out an inventory on the management of FGR in teaching hospitals and tertiary referral centers MATERIAL AND METHODS: We carried out a retrospective survey on the academic year 2020/2021. All teaching hospitals and level III maternity in mainland France were contacted (67). The questionnaire focused on the growth curves used, the etiological assessment carried out, the rate and modalities of antenatal surveillance as well as the criteria indicating a birth.

RESULTS

The response rate was 76%. The CFEF curves are used for screening in 78.4% of centers and in the event of FGR in 39.2% of them. The etiological assessment includes a referent ultrasound in 62.7% of cases and amniocentesis is offered in 74.5% of hospitals in case of severe and early FGR. All centers use umbilical Doppler for FGR. The fetal heart rate is monitored between once a week to three times a day in the event of cerebro-placental redistribution. In case of reverse flow, birth is induced from 28 weeks on for some teams while others continue the pregnancy until 39 weeks. In case of cessation of fetal growth, the expected terms of birth are between 28 and 38 weeks.

CONCLUSION

There is great heterogeneity in the management of FGR, particularly in terms of antenatal surveillance and the term of birth envisaged.

Utility of Neonatal Ophthalmologic Examination for Detection of Infectious Etiologies for Symmetric Intrauterine Growth Restriction

OBJECTIVE

To determine the utility of ophthalmologic examination as part of evaluation for infection in infants with intrauterine growth restriction (IUGR).

STUDY DESIGN

This is a single-institution retrospective chart review of neonates diagnosed with symmetric IUGR or small for gestational age (SGA) who underwent complete ophthalmologic consultation to assess for intraocular findings suggestive of congenital infection. Data collected included other factors that may cause IUGR, findings of general and ophthalmologic examinations, and results of investigation for intrauterine infection. Cost minimization analysis was also performed.

RESULTS

One hundred neonates met the study's inclusion criteria (IUGR, n = 24; SGA, n = 45; IUGR and SGA, n = 31). The mean gestational age at birth was 34.6 ± 3.0 weeks, and the mean birth weight was 1691 ± 530 g; 74% had an identifiable risk factor for IUGR and 84 patients underwent investigation for intrauterine infection. Two of the 73 patients who had urine culture for cytomegalovirus (CMV) were positive (1 of whom had systemic signs of severe congenital infection without eye involvement, the other who had no clinical signs of congenital CMV); evaluations for infection were negative otherwise. No patients had any ophthalmologic signs of congenital infection.

CONCLUSIONS

Current literature suggests that routine evaluation of neonates with isolated IUGR for congenital infection may be low-yield and not cost-effective. Our study found that routine ophthalmologic evaluation in newborns with symmetric IUGR who have no systemic signs of intrauterine infection is of little value.

[Histopathological lesions of the placenta associated with severe intrauterine growth retardation: about a clinical case]

L'examen du placenta est indispensable dans le diagnostic du retard de croissance intra-utérin (RCIU). Son intérêt réside dans la recherche étiologique de cette pathologie, et les conséquences materno-fœtal qui peuvent en découler, ainsi dans la mise en place des stratégies préventive lors des grossesses ultérieures dans le cas des pathologies récidivantes. Nous rapportons les lésions anatomopathologiques possibles retrouvées au niveau du placenta de cette pathologie à travers une observation de RCIU sévère suivi au sein du Service de Néonatologie du CHU Ibn Sina de Rabat.

IUGR and infections

Intra-uterine growth retardation (IUGR) is usually defined as impaired growth and development of the fetus and/or its organs during gestation. Infants are defined small for gestational age (SGA), following IUGR, when the birth weight is below the 10th percentile. Pre-natal congenital infections caused by T. gondii, rubella, cytomegalovirus (CMV), herpes simplex virus (HSV), varicella-zoster virus (VZV), and Treponema are associated with, and account for, approximately 5 to 15% of IUGR. On the other hand, SGA preterm infants are at increased risk of post-natal infection compared to their age-matched appropriately grown controls, in particular nosocomial infection, irrespective of the responsible pathogen. One possible mechanism is the retarded development in the immune system which has been described in association with IUGR. Indeed, SGA infants have a disproportionately small thymus and low leukocyte, lymphocyte and macrophage counts. However, immune therapies, including prophylactic intravenous immunoglobulins and GM-CSF have not proven to be effective in reducing the incidence of sepsis, and further research is required.

Management of pregnancies with confirmed cytomegalovirus fetal infection

Systematic screening for cytomegalovirus (CMV) maternal infection is not recommended in most countries. Nevertheless, primary CMV infection will occur in around 1% of women. The vertical transmission rate is estimated to be around 30-50%. Newborns with congenital CMV infection remain asymptomatic in the majority of cases and around 10% will present with a wide range of abnormalities. Fetal infection can be diagnosed by amniocentesis with amplification of the viral genome in the amniotic fluid by polymerase chain reaction. This prenatal diagnosis is mainly performed when ultrasound abnormalities are observed. The purpose of this mini-review is to describe the management options when a fetus is known to be infected.