P.R. Hein
Radboud University Nijmegen
Network
Latest external collaboration on country level. Dive into details by clicking on the dots.
Publication
Featured researches published by P.R. Hein.
European Journal of Obstetrics & Gynecology and Reproductive Biology | 1991
E.A.P. Steegers; T.K.A.B. Eskes; H.W. Jongsma; P.R. Hein
This article reviews the major milestones in obstetric research in the past 90 years, which have lead to the wide-spread use of salt restriction during pregnancy. Possibly the most ardent advocate of the view that salt plays a crucial role in eclampsia was De Snoo (1877-1949), a Dutch obstetrician. However, despite many enthusiastic clinical reports, no convincing evidence has ever been produced that salt restriction helps in the prevention of hypertension during pregnancy.
European Journal of Obstetrics & Gynecology and Reproductive Biology | 1988
E.A.P. Steegers; G. Buunk; R.A. Binkhorst; H.W. Jongsma; P.F.F. Wijn; P.R. Hein
The effects of maternal exercise were studied in 20 healthy women with uncomplicated pregnancies. A continuous-wave Doppler ultrasound system was used to record arterial flow velocity waveforms from the ascending vasculature downstream from the uterine artery. The fetal heart rate was monitored with a Doppler ultrasound cardiotocograph. No significant change was found in the uterine blood flow velocity waveform post-exercise, as expressed by the pulsatility index, suggesting absence of change in the uterine vascular bed resistance. The fetal heart rate significantly increased after exercise.
Gynecologic and Obstetric Investigation | 1990
E.A.P. Steegers; J.M.G. Hollanders; H.W. Jongsma; P.R. Hein
Synthesis and secretion of atrial natriuretic peptide (ANP) is not confined to the heart, but also present in other tissues. ANP is known to affect steroidogenesis in the ovary. To assess the possibilities that (a) the human ovary is a source of ANP secretion as well, and (b) ovarian ANP stimulates progesterone secretion, we investigated ANP as well as progesterone concentrations in preovulatory ovarian follicular fluid form women in an in vitro fertilization program. In all women detectable ANP immunoreactivity was found in ovarian follicular fluid (range 3.3-60.1 pg/ml). Follicular fluid concentrations were low in all but 1 women who demonstrated a higher ANP level in follicular fluid than in plasma. Follicular ANP and progesterone concentrations were not significantly correlated. These preliminary results suggest that the ovary could well be a site of ANP secretion. If and how ovarian ANP activity affects progesterone secretion remains as yet unknown.
European Journal of Obstetrics & Gynecology and Reproductive Biology | 1987
E.A.P. Steegers; P.R. Hein; A.C.I.T.L. Tan; E.A.M. Groeneveld; H.W. Jongsma; Th. J. Benraad
Plasma concentrations of atrial natriuretic peptide (ANP) were determined ante- and post-partum in 7 healthy primiparous women. ANP was measured at weekly intervals from the 35th week of pregnancy onwards and throughout the puerperium up to the sixth week post-partum. In all seven patients the mean of the ANP values during the first four days post-partum was higher than in late pregnancy. The mean ANP level from the 6th day up to the 42nd day showed a marked decrease compared with the first four days after birth, which, however, did not differ significantly from the mean plasma concentration in late pregnancy. In conclusion, ANP is markedly elevated during the first few days post-partum compared with plasma levels in the normal late pregnancy and the subsequent puerperium.
European Journal of Obstetrics & Gynecology and Reproductive Biology | 1983
H.W.H. Feijen; P.R. Hein; E.L. van Lakwijk-Vondrovicova; G.M.M. Nijhuis
To the best of our knowledge no recent literature on pregnancy in patients with primary pulmonary hypertension is available. In this case report a patient is presented who possibly suffered from primary pulmonary hypertension. The clinical course is described and some data from the literature are presented. The patient died post partum probably due to this disease; however, the postmortem examination, which undoubtedly could have proven this, was refused.
European Journal of Obstetrics & Gynecology and Reproductive Biology | 1988
P.R. Hein; J.S.J.O. Schatorjé; H.J.A.A.M. Frencken
A generally accepted management of heroin addiction during pregnancy is treatment with methadone, which reduces the complications of heroin addiction considerably. Reports in the literature are still contradictory, however, about the influence of methadone upon birthweight. In pregnant Cynomolgus monkeys (Macaca fascicularis) the effect of chronic treatment with rather high dosages of methadone upon birthweight was studied under standardized conditions. Birthweights were significantly lower in the methadone-treated animals.
European Journal of Obstetrics & Gynecology and Reproductive Biology | 1978
P.R. Hein; J.L.J. Jansen; F.M.J. Debruyne
A successful pregnancy is reported in a patient following renal transplantation and urinary diversion. The second half of pregnancy was complicated by hypertension, impaired renal function and obstruction of the ureter in the 35th wk. The latter complication required early termination of pregnancy by cesarean section. A healthy infant was delivered who survived without complications. Maternal renal function returned to pre-pregnancy levels following delivery.
European Journal of Obstetrics & Gynecology and Reproductive Biology | 1991
P.R. Hein; J.S.J.O. Schatorjé; H.J.A.A.M. Frencken; M.F.G. Segers; C.M.G. Thomas
The effect of chronic methadone treatment upon the serum levels of Estradiol (E2), Progesterone (P), Prolactin (Prl), monkey chorionic gonadotropin (mCG), dehydroepiandrosterone sulfate (DHEAS) and Cortisol (C) in pregnant Cynomolgus monkeys (Macaca fascicularis) is described in comparison with the hormone levels in a control group. Only DHEAS was significantly decreased in late pregnancy in the methadone group. From these data it can not be concluded that methadone treatment compromises (feto)placental function. The observed intra-uterine growth retardation in the methadone treated group might be a result of a direct influence of methadone upon growth.
European Journal of Obstetrics & Gynecology and Reproductive Biology | 1985
P.R. Hein; J.M. Boon
Morbidity in the first year of life of 120 infants, born before the 34th wk of pregnancy, was studied in relationship to both duration of pregnancy and birthweight. Moreover, the interrelationships of morbidity in three time-periods (first-hour, first 28 days and first year after delivery) were studied. The major handicap rate at one year was 5%, without major handicaps in infants born before 29 wk or weighing less than 1250 g. This finding seems to justify intensive treatment of even the youngest and smallest infants. Significantly more morbidity in the first 28 days of life was found when intervention within the first hour after delivery was necessary, indicating that morbidity in the first hour after delivery may be a prognostic bad sign for morbidity in the first 28 days of life. However, no significant differences in handicap rates at one year of age were found in infants with and without morbidity in the first hour or in the first 28 days. This indicates that early morbidity will not necessarily be followed by morbidity in later life, but, on the other hand, absence of early morbidity does not preclude handicaps later on.
European Journal of Obstetrics & Gynecology and Reproductive Biology | 1985
T. de Boo; J.M. Boon; P.R. Hein
Survival of 188 infants born alive before the 34th wk of pregnancy is assessed in relation both to birthweight and duration of pregnancy. A logistic model is used which describes, based on these parameters, probabilities of 1-yr survival of relatively small populations in a continuous way. Although there may be differences between measured and estimated birthweight, this method might enable the perinatologist to estimate before birth the survival probabilities if he knows the duration of pregnancy and estimated birthweight.