Wallace Jacqueline M, Milne John S, Adam Clare L, Aitken Raymond P
The Rowett InstituteUniversity of Aberdeen, Aberdeen, UK
The Rowett InstituteUniversity of Aberdeen, Aberdeen, UK.
Reproduction. 2017 Apr;153(4):381-394. doi: 10.1530/REP-16-0590. Epub 2017 Jan 9.
The influence of maternal obesity during oocyte development and its putative interaction with nutrient reserves at conception on pregnancy outcome were examined in an adolescent sheep model. Donor ewes were nutritionally managed to achieve contrasting adiposity (control (CD)/obese (ObD)) for 6 weeks prior to superovulation and inseminated by a non-obese sire. Morulae from 6 CD and 7 ObD were transferred in singleton into adolescent recipients of identical age but differing adiposity, classified as relatively fat or thin respectively. Thereafter, all were overnourished to promote rapid growth/adiposity (2 × 2 design, 13/14 pregnancies/group). A fifth recipient group of intermediate adiposity received embryos from another 5 CD, was offered a moderate intake to maintain adiposity throughout gestation and acted as controls for normal pregnancy outcome (optimally treated control (OTC), 19 pregnancies). Donor obesity did not influence ovulation, fertilisation or recovery rates or impact embryo morphology. Gestation length and colostrum yield were unaffected by donor or recipient adiposity and were reduced relative to OTC. Total fetal cotyledon and lamb birth weights were independent of initial donor adiposity but reduced in relatively thin vs relatively fat recipients and lower than those in the OTC group. In spite of high placental efficiency, the incidence of fetal growth restriction was greatest in the thin recipients. Thus, maternal adiposity at conception, but not pre-conception maternal obesity, modestly influences the feto-placental growth trajectory, whereas comparison with the OTC indicates that high gestational intakes to promote rapid maternal growth remain the dominant negative influence on pregnancy outcome in young adolescents. These findings inform dietary advice for pregnant adolescent girls.
在一个青春期绵羊模型中，研究了卵母细胞发育期间母体肥胖的影响及其与受孕时营养储备的假定相互作用对妊娠结局的影响。在超数排卵前6周，对供体母羊进行营养管理，以实现不同的肥胖程度（对照（CD）/肥胖（ObD）），并由一只非肥胖的公羊进行授精。将来自6只CD和7只ObD的桑葚胚单胎移植到年龄相同但肥胖程度不同的青春期受体中，分别归类为相对肥胖或消瘦。此后，所有受体均过度营养以促进快速生长/肥胖（2×2设计，每组13/14次妊娠）。第五组中等肥胖程度的受体接受来自另外5只CD的胚胎，在整个妊娠期给予适度摄入量以维持肥胖程度，并作为正常妊娠结局的对照（最佳治疗对照（OTC），19次妊娠）。供体肥胖不影响排卵、受精或回收率，也不影响胚胎形态。妊娠期长度和初乳产量不受供体或受体肥胖程度的影响，相对于OTC有所降低。胎儿总子叶和羔羊出生体重与初始供体肥胖程度无关，但在相对消瘦的受体中低于相对肥胖的受体，且低于OTC组。尽管胎盘效率很高，但胎儿生长受限的发生率在消瘦受体中最高。因此，受孕时的母体肥胖而非受孕前的母体肥胖适度影响胎儿-胎盘生长轨迹，而与OTC组的比较表明，促进母体快速生长的高妊娠期摄入量仍然是对年轻青少年妊娠结局的主要负面影响。这些发现为怀孕少女的饮食建议提供了依据。
