Marŝál K, Gennser G, Kullander S
Obstet Gynecol. 1978 Feb;51(2):163-5.
Fetal breathing movements in 14 twin pregnancies were examined with ultrasonic technique. The twin fetuses I in cephalic presentation showed a significantly higher percentage of apnea and periodic breathing compared with twin fetuses II. No such difference was found in twin pairs with Twin ti in breech presentation. Also in the control group of 27 singleton pregnancies, the fetuses in cephalic presentation had a higher incidence of apnea and periodic breathing than those in breech presentation. The position of the fetus seems to be decisive for the character of the breathing movements before birth.
采用超声技术对14例双胎妊娠的胎儿呼吸运动进行了检查。头先露的双胎胎儿I与双胎胎儿II相比，呼吸暂停和周期性呼吸的发生率显著更高。臀先露的双胎对中未发现此类差异。同样，在27例单胎妊娠的对照组中，头先露胎儿的呼吸暂停和周期性呼吸发生率高于臀先露胎儿。胎儿的体位似乎对出生前呼吸运动的特征起决定性作用。
