PROTEIC-CALORIC RESTRICTION DURING PREGNANCY AFFECTS THE ADRENAL-PLACENTAL AXIS AND DECREASES BIRTH-WEIGHT IN A PRIMATE, CEBUS-APELLA, WITHOUT AFFECTING GESTATIONAL LENGTH

Objective To assess the effect of mild maternal undernutrition upon th e maternal adrenal-placental axis, birth weight and length of gestatio n in a primate model. Study design We subjected a group of six female Cebus apella to a restricted diet (12% protein, 730 cal/day) from day 21 of pregnancy (term = 155 days). Twelve females fed standard diet (1 9% protein, 912 cal/day) were used as controls. Between 125 and 145 da ys of gestation, we measured maternal plasma 17 beta-estradiol as an i ndirect indicator of fetal adrenal function and cortisol as an indicat or of maternal adrenal function. Also, we determined newborn weight an d gestational age (CA) at birth. Results Plasma 17 beta-estradiol conc entrations were 27.1 +/- 4.6 ng/ml in the restricted diet group compar ed to 57 +/- 5.3 ng/ml in the standard diet group (p = 0.001), while p lasma cortisol concentrations were 3.4 +/- 0.28 mu g/ml and 2.05 +/- 0 .2 mu g/ml, respectively (p = 0.006). Mean newborn weight was 177.5 +/ - 5.3 g in the restricted diet group versus 194.6 +/- 5.3 g in the con trol group (p > 0.1), while mean length of gestation was 156 +/- 2.1 d ays and 154 +/-1.0days, respectively (p < 0.05). Conclusions Maternal. undernutrition produced a significant decrease in birth weight, matern al 17 beta-estradiol and progesterone, and an increased maternal corti sol. Despite all these changes there was no alteration in gestational length. Whether these changes are mediated by glucose, by other homoeo static mechanisms or whether they are mediated by stress is unclear at the present time.