Australian Birth Defects Society

A Society devoted to the study of birth defects

Quick round-up of interesting articles that have passed my desk this month.

Journal Club

Risk estimates of recurrent congenital anomalies in the UK: a population-based register study BMC Medicine (2017) 15:20

This study from North England, UK over 1985–2010 included 872,493 singleton stillbirths, live births and terminations of pregnancy for fetal anomaly. For women whose first pregnancy was affected by congenital anomaly, the absolute risk of recurrent congenital anomaly in the second pregnancy was ~1 in 25 (2.5 times higher than for those with unaffected first pregnancies). This reassuring news for women whose first pregnancy was affected by a congenital anomaly and who are planning a further pregnancy.

 

Primary maternal cytomegalovirus infections: accuracy of fetal ultrasound for predicting sequelae in offspring Am J Obstet Gynecol 2016;215:638.e1-8.

How accurate is fetal ultrasound for predicting sequelae in babies following maternal cytomegalovirus infection? An analysis of 67 patients with proven vertical transmission found fetal ultrasound anomalies in 37.7% of babies which was confirmed in 73.9% postnatally. Postnatal clinical evaluation also detected CMV-related anomalies in 55% of infants with normal fetal ultrasound evaluations.

 

Prevalence of microcephaly in an Australian population-based birth defects register, 1980-2015 Med J Aust. 2017 206(8):351-356.

Microcephaly cases defined as occipito-frontal head circumference below the third percentile or more than two standard deviations below the sex- and age-appropriate mean were ascertained by the WA Register of Developmental Anomalies, 1980-2015. In that time, 416 cases were identified, 5.5 per 10 000 births, or 1 in 1830 births. There was no significant temporal trend in prevalence. Most cases were liveborn (93.5%), and 80% had other major birth defects. Prevalence was higher in Aboriginal births (PR, 4.5). The most frequent known cause of microcephaly in Aboriginal births was fetal alcohol spectrum disorder; while monogenic chromosomal were the most common causes in non-Aboriginal births.

Maternal and infant genetic variants, maternal periconceptional use of selective serotonin reuptake inhibitors, and risk of congenital heart defects in offspring: population based study. BMJ 2017;356:j832 DOI: 10.1161/HYPERTENSIONAHA.116.08773.) •

Common maternal or infant genetic variants in folate, homocysteine, or transsulfuration pathways are associated with an increased risk of certain congenital heart defects among children of women taking SSRIs during cardiogenesis.

June 2017

April 2017

Page updated 8 June 2017

Human teratogens and genetic phenocopies. Understanding pathogenesis through human genes mutation. Eur J Med Genet 60 (2017) 22e31

Exposure to teratogens sometimes results in recognizable patterns of malformations,. What complicates diagnosis is that several genetic syndromes are phenocopies of some of these malformations. Genetic phenocopies are often caused by mutations in genes which are targets of these teratogens or part of the same molecular pathways. This paper reviews some of the suspected genetic phenocopies of prenatal exposure to warfarin, leflunomide, mycophenolate mofetil, fluconazole, thalidomide and ACE inhibitors.

 

The impact of thalidomide use in birth defects in Brazil Eur J Med Genet 60 (2017) 12e15

Between 1969-1995, 34 cases of thalidomide embryopathy were reported in South America. Despite restrictions there were three new cases in 2005 and 2006; in two of the cases, the mothers procured thalidomide through a close relative.

 

Detection of fetal abnormalities by second-trimester ultrasound screening in a non-selected population. Acta Obstet Gynecol Scand 96 (2017) 176–182 

This study assessed the sensitivity of routine ultrasound examination for the detection of abnormal chromosomes and structural malformations in fetuses in the second trimester by comparing the frequency of prenatal diagnoses of fetal abnormalities through routine ultrasound examination to that confirmed at birth.  The study found that the prenatal detection rate of chromosomal abnormalities was 60.7% and 39.0% for structural malformations.