Hermogenes Alvarez Bengoa, Uruguayan ginecologist and obstetrician (Nico Perez, Florida Department 1905 – Montevideo 1984)

WITH CALDEYRO-BARCÍA

First obtained records of intrauterine amniotic pressure during childbirth defining intensity, contraction rate, inner tonus and uterine activity (1947). These were the first records of human uterus activity during labor

Established the descending triple gradient law (1949)

Developed Montevideo unit of uterine performance (1949)

First recorded intramiometrial pressure in distinct parts of uterus during childbirth establishing the source and propagation of wave of uterine contraction (1950)

Established two kinds of contraction during pregnancy

Established the concept of uterine tonus, its effects and variations

Described the pain, emotions and remedies influence on uterine conductivity 

Independent from Edward Hon described main changes of fetal cardiac rate produced via uterine contractions which became later the basis of fetal monitoring (1958)

Eponym of Alvarez-Caldeyro Barcia microballoon

World Pioneer on amniocentesis and chorionic biopsy

Proposed the biopsy of choral villi (1960)

Discovered the existence of a coordination between both uterine hemispheres in normal labor

Established the physiology of delivery

Introduced the placental trans-abdominal biopsy by direct puncture (1961)

Created “placental rating”

Established the concept of trophoblastic development

Developed the method for studying the human placenta using phase contrast microscopy