Extramembranous pregnancy in twin gestation.

Area of Science:

• Perinatology
• Developmental Biology
• Medical Genetics

Background:

• Twin pregnancies present unique challenges in fetal development and maternal care.
• Extramembranous development is a rare condition affecting fetal membranes.
• Potter facies (dysplasia renofacialis) is a pattern of facial anomalies associated with renal agenesis or severe renal disease.

Observation:

• Described is an unusual case of extramembranous development in one twin during a twin pregnancy.
• The pregnancy was complicated by intermittent oligohydramnios and vaginal bleeding from 26 weeks gestation.
• Delivery at 32 weeks resulted in a normal infant and a second twin with features of Potter facies, who died shortly after birth.

Findings:

• The affected twin exhibited characteristics of dysplasia renofacialis (Potter facies).
• The diamniotic, dichorionic gestation involved a single placenta where the affected twin's side was markedly circumvallate.
• Short, thick membranes covered less than 10% of the affected infant.

Implications:

• This case underscores the importance of recognizing rare fetal developmental anomalies in twin gestations.
• Understanding the placental morphology and membrane characteristics may offer insights into fetal development.
• Further research into the etiology of extramembranous development and its association with conditions like Potter facies is warranted.