The effect of maternal exercise on umbilical artery blood flow in pregnancy-induced hypertension.

Seventeen in-patients with pregnancy-induced hypertension (PIH) in the last trimester of pregnancy underwent an exercise stress test. The mean exercise intensity achieved was 66% (55-77%) of submaximal exercise. The mean maternal heart rate rose significantly from a mean of 89 beats per minute (64-110 bpm) to a mean of 144 bpm (120-168 bpm) after exercise. The mean systolic blood pressure rose significantly from a mean of 149 mmHg (130-170 mmHg) to a mean of 171 mmHg (150-190 mmHg). The diastolic blood pressure rose from a mean of 102 mmHg (100-110 mmHg) to a mean of 106 mmHg (100-115 mmHg). In patients with systolic blood pressure of 180-190 mmHg, their fetuses had significantly higher systolic/diastolic (S/D) ratios before and after exercise than those with blood pressure of 150-170 mmHg. The PI showed sharp fluctuations but the changes were not significant. The mean S/D and the PI decreased at 2, 4, 6 and 8 minutes of recovery from baseline values at rest. Subsequently it rose significantly to peak at 20 minutes of recovery. No evidence of ill effect from the exercise test was noted on any of the mothers or their fetuses. All pregnancies resulted in a good outcome.

The effect of maternal exercise on umbilical artery blood flow in insulin-dependent diabetics.

Nine insulin-dependent diabetic women underwent a moderate exercise test. The mean exercise intensity achieved was 65% (50-80%) of submaximal exercise. The maternal heart rate rose significantly after exercise from a mean of 85 b.p.m. (60-109 b.p.m.) to a mean of 140 b.p.m. (112-168 b.p.m.). Maternal systolic blood pressure rose significantly from a mean of 115 mmHg (90-130 mmHg) to a mean of 157 mmHg (145-180 mmHg). The diastolic blood pressure also rose, but insignificantly, from a mean of 71 mmHg (65-90) mmHg to a mean of 85 mmHg (80-90) mmHg after exercise. The mean umbilical pulsatility index (PI) showed significant decrease at 2 and 6 minutes of recovery from exercise and subsequently showed a significant rise after 20 minutes. This rise continued even after a full 30 minutes of recovery from exercise.

The effect of maternal exercise on fetal heart rate.

One hundred and ninety-three women with uncomplicated pregnancies and 44 with high-risk pregnancies participated in a 5-minute exercise stress test on a bicycle ergometer. All women were in the third trimester of pregnancy. Measurements of fetal heart rate were made at intervals of 2, 4, 6, 8, 10, 12, 16, 20, 25 and 30 minutes. Fetal heart rate was then compared in terms of maternal age, parity, consumption of cigarettes, exercise intensity, history of activity, cardiotocography score, maternal heart rate at rest, maternal heart rate after exercise, fetal sex and birth weight. In low-risk pregnancies an increase in fetal heart rate from 143 (124-171) beats per minute (bpm) to 148 (116-191) bpm was noted after exercise while, in the high-risk pregnancy group, a transient decrease from 148 (115-170) bpm to 141 (70-180) bpm was observed. There were also 10 cases of significant bradycardia in the high-risk pregnancy group. We conclude that the effect of maternal exercise on fetal heart rate is dependent on many variables. A fetal bradycardia following exercise is more likely to occur in high-risk pregnancies. The use of fetal heart rate variation with exercise could be a useful prognostic factor in pregnancy.

Umbilical artery flow velocity waveforms following maternal exercise.

The effect of acute exercise on pregnant women in the last trimester of pregnancy and the changes in fetal umbilical artery flow velocity waveforms were studied. One hundred and forty-three healthy pregnant women underwent an acute exercise test. The exercise was performed on an upright bicycle ergometer for 5 minutes, followed by 30 minutes of recovery. The baseline control values of umbilical artery velocity waveforms were compared with those after exercise. The mean exercise intensity achieved was 67.4% (55-90%) of submaximal exercise. Maternal heart rate rose significantly from a mean of 89 (68-120) beats per minute at rest to a mean of 144 (116-200) beats per minute after exercise (P<0.001). Maternal blood pressure rose significantly after exercise from a mean systolic of 112 (80-150) mmHg to a mean of 147 (120-200) mmHg (P<0.001), and from a mean diastolic of 67 (40-85) mmHg to a mean of 84 (70-100) mm Hg (P<0.001). The mean fetal umbilical pulsatility index (PI) was shown to decrease significantly following exercise at 2 and 4 minutes of recovery. It is concluded that (1) an acute exercise test of this intensity causes a significant decrease in PI index after 2 and 4 minutes of recovery; (2) an exercise intensity between 55 and 75% causes a decrease in the PI after exercise while exercise of 76-90% of submaximal exercise causes a rebound increase after an initial decrease at 2 minutes; (3) it may be possible to use this pattern of exercise as an exercise test to differentiate between low- and high-risk pregnancies. Studies on high-risk pregnancies are being prepared for publication.

The effect of maternal exercise on umbilical artery velocimetry waveforms in intrauterine growth retardation.

Eighteen pregnant women affected with fetal growth retardation in the last trimester were exercised. The mean maternal heart rate increased significantly from 140 beats per minute (bpm) (120-188 bpm) at rest to 172 bpm (163- 178 bpm) after exercise. The mean exercise intensity was 65% (56-85%) of submaximal exercise. Maternal systolic blood pressure rose significantly from a mean of 116 mmHg (100-140 mmHg) to 159 mmHg (120-190 mmHg) and the diastolic blood pressure rose significantly from a mean of 72 mmHg (55-110 mmHg) to 90 mmHg (80-110 mmHg). The umbilical artery pulsatility index (PI), after an initial decrease, showed a 12% rise at 8, 16 and 30 minutes of recovery. Patients who smoked had a significantly higher umbilical artery PI before and after exercise. Less active Patients had a higher PI before and after exercise than active ones. Infants weighing 1.9-2.5 kg at birth had a higher PI than those weighing 2.6-3.3 kg. Male fetuses had a significantly higher PI than female fetuses.

The effect of maternal exercise on uterine artery velocimetry waveforms.

One hundred and two subjects in the second half of pregnancy were subject to an acute exercise test lasting 5 minutes on an upright bicycle ergometer. The pulsatility index (using Doppler ultrasound) of the right uterine artery was analysed before exercise and at 2, 4, 6, 8, 10, 12, 16, 20, 24 and 30 minutes after exercise. The mean exercise intensity achieved was 67.2% of sub-maximal exercise (range 51-90%). At 2 minutes post-exercise, the mean uterine artery pulsatility index was increased from the baseline value, reaching a maximum of 0.64 at 8 minutes (baseline 0.583). After 8 minutes there was a gradual decrease in the pulsatility index, and at 24 and 30 minutes the values were significantly lower (P < 0.001 and P < 0.001 respectively). Smokers had significantly higher pulsatility index values than non-smokers (P < 0.004). Primigravidae also had lower resistance indices compared with multigravidae (P < 0.001). We conclude that exercise in the second half of pregnancy appears to cause a transient increase in the maternal uterine artery pulsatility index. We also believe that at this level of exercise intensity there was no evidence of harmful effects on maternal uterine blood flow.

Classical caesarean section through the posterior uterine wall.

We report a case of myomectomy and classical caesarean section through the posterior uterine wall necessitated by 180 degrees dextro-rotation of a gravid uterus with large fibroids. The non-specific clinical course and rarity of pathological torsion of the gravid uterus makes the preoperative diagnosis difficult. Ultrasound recognition antenatally of a fibroid changing its position should help with the prediction preoperatively of uterine rotation.

The effect of maternal exercise on fetal umbilical artery waveforms.

Twenty-one nulliparous women in the last trimester of pregnancy gave their informed verbal consent to undergo an acute exercise test. Fetal umbilical artery velocimetry waveforms were measured to monitor the effect of exercise on fetal umbilical artery blood flow. The mean gestational age was 32 weeks (range 28-37 weeks). The mean exercise intensity was 71% of submaximal exercise (range 67-74%). Maternal heart rate rose significantly (P less than 0.001) from a mean of 83 to 138 beats per min. Following moderate exercise, the systolic over the diastolic ratio (S/D) decreased significantly (P less than 0.001) after 2 and 20 min. This indicates a decrease in umbilical blood flow resistance and an improved placental circulation following exercise in healthy women. We conclude that maternal exercise does not appear to be harmful to the mother or her fetus at this level of exercise intensity in healthy individuals.

Thanatophoric dwarfism; drugs and antenatal diagnosis; a case report.

Thanatophoric dwarfism is not as rare as once thought. We present this case because of the possible association with drug administration and the probability of diagnosing this condition antenatally.

The use of Doppler umbilical artery waveforms in placental abruption; a report of two cases.

In a prospective study, the predictive value of Doppler umbilical arterial velocimetry waveforms in detecting the fetus at risk was examined in ten patients with abruptio placenta. One patient suffered intra-uterine fetal death within 8 h of obtaining a normal reactive cardiotocograph and normal umibilical artery waveforms. In another patient with severe placental abruption, following 2500 ml of blood loss, the umbilical artery waveforms were normal. In this study, umbilical artery waveforms failed to predict fetal outcome in cases of placental abruption.

Stillbirths: a clinicopathological survey (1972-1982).

A survey of 325 stillbirths from 27,072 babies delivered at University College Hospital Galway from April 1, 1972 to March 31, 1982, gave a stillbirth rate of 12 per thousand, which, when corrected for 66 lethal congenital abnormalities, became 9.6 per thousand. The cause of death in each stillbirth was determined clinically and pathologically where possible and was classified according to a modified Aberdeen classification of perinatal death. Consideration of the birth weights of the babies who died showed that 223 (68.6%) weighed over 1,500 g, and excluding those with abnormalities, they must be considered salvageable with the application of intensive neonatal care. There were 54 (16.6%) intrapartum deaths, which must also be considered preventable. The application of ultrasonic surveillance should complement clinical acumen, by allowing easier detection of the fetus at risk, thereby facilitating earlier intervention which in turn should reduce antenatal stillbirths.

Surveillance of triplets with umbilical artery velocimetry waveforms.

Doppler arterial velocimetry waveforms was used as a method of antenatal surveillance for triplets. Six sets of triplet pregnancies were studied. Each fetus was identified by real-time-ultrasound scanning and the peak systolic/end diastolic (S/D) ratio was calculated. In one set of triplets two fetuses showed absent end diastolic flow. Both subsequently suffered from necrotising enterocolitis and had major bowel resection. The five other sets of triplets maintained a normal S/D ratio. Three had a normal outcome and two delivered prematurely.