Dornan J C, Ritchie J W
Br J Obstet Gynaecol. 1983 Mar;90(3):210-3. doi: 10.1111/j.1471-0528.1983.tb08610.x.
The effect of fetal breathing movements (FBM) of maternal breathing of 50% oxygen was examined. The procedure caused a two-fold rise in maternal arterial Po2 and did not alter FBM in normal pregnancy. In pregnancy complicated by intrauterine growth retardation (IUGR) a substantial increase in the incidence of FBM was recorded during hyperoxia (control 29.8 +/- 3.9%, hyperoxia 68.2 +/- 3.6). No such change was observed in pregnancies where IUGR was suspected but not proven at delivery.