Sex differences in regional specialisation across the placental surface.
There may be regional specialisation in structure and function across the placental surface. In Riyadh, Saudi Arabia, the length and the breadth of the placental surface at birth were highly correlated, but the breadth was more closely associated with the size of the baby. To replicate this we studied 321 pregnant Saudi women in the town of Baish. We measured the size of the newborn babies and their placentas. The association of the length and breadth of the placental surface on the baby's body size differed in boys and girls. Among boys the breadth had a stronger association with all birth measurements except crown-heel length. This was similar to the findings in Riyadh. Placental surface length was related to crown-heel length. For each centimetre in surface length, crown-heel length increased by 0.27 cm (95% CI 0.09-0.44, p = 0.004). Among girls placental surface breadth was related to crown-heel length, whereas surface length was related to birth weight, head and thigh circumferences. For each centimetre in surface breadth, crown-heel length increased by 0.33 cm (0.13-0.53, p = 0.001). We conclude that, within Saudi Arabia, there are both geographical and sex differences in regional specialisation across the placental surface. In the adverse circumstances of Baish, linked to the mothers' short stature, boys were smaller at birth than girls. Boys may have compensated for under-nutrition by increasing the depth of spiral artery invasion rather than by recruiting additional spiral arteries. Girls may have had more effective regional specialisation across the placental surface.
Fetal Programming of Disease Research Chair, Zoology Department, College of Science, King Saud University, Saudi Arabia. Electronic address: salwasel@ksu.edu.sa.
S H
SH
Alwasel
Zoology Department, College of Science, King Saud University, Saudi Arabia.
A H
AH
Harrath
Fetal Programming of Disease Research Chair, Zoology Department, College of Science, King Saud University, Saudi Arabia.
W M
WM
Aldahmash
Obstetrics and Gynecology Department, King Saud University, Saudi Arabia.
Z
Z
Abotalib
Fetal Programming of Disease Research Chair, Zoology Department, College of Science, King Saud University, Saudi Arabia; Stereology and Electron Microscopy Laboratory Centre for Stochastic Geometry and Advanced Bioimaging, Department of Clinical Medicine, Aarhus University, Denmark.
J R
JR
Nyengaard
MRC Lifecourse Epidemiology Unit, Medical School, University of Southampton, UK.
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C
Osmond
Maternal and Fetal Health Research Centre, Institute of Human Development, University of Manchester, UK; Mary's Hospital, Central Manchester University Hospitals NHS Foundation Trust, Manchester Academic Health Science Centre, Manchester, UK.
M R
MR
Dilworth
Fetal Programming of Disease Research Chair, Zoology Department, College of Science, King Saud University, Saudi Arabia.
S Y
SY
Al Omar
Faculity of Applied Medical Sciences, Jazan University, Saudi Arabia.
A A
AA
Jerah
Fetal Programming of Disease Research Chair, Zoology Department, College of Science, King Saud University, Saudi Arabia; MRC Lifecourse Epidemiology Unit, Medical School, University of Southampton, UK.
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Barker
D000886:Anthropometry; D001724:Birth Weight; D001827:Body Height; D049628:Body Size; D005260:Female; D047109:Fetal Development / Q000502:physiology; D005865:Gestational Age; D006801:Humans; D007231:Infant, Newborn; D008297:Male; D008423:Maternal Age; D009035:Mothers; D010298:Parity; D010920:Placenta / Q000033:anatomy & histology / Q000502:physiology*; D011247:Pregnancy; D012529:Saudi Arabia; D012727:Sex Characteristics
Neonatal size; Placental surface; Regional specialisation; Sex differences