Modulation by continuous oestrogen treatment and by progesterone of oestrogen receptors in the rabbit uterus.

The effect of continuous oestrogen treatment on uterine weight, and on cytoplasmic and nuclear oestrogen receptors was examined in rabbits. Modulation of the effects of oestrogen by progesterone was also studied. Uterine weight increased successively after exposure to oestrogen from 1 to 6 days. The concentration of both cytosolic and nuclear oestrogen receptors decreased in almost parallel fashion, however, irrespective of whether it was expressed per microgram protein or microgram DNA. Treatment with progesterone 5 days after oestrogenization caused no significant change in uterine weight at first. The oestrogen receptor concentration in both cytosolic and nuclear fractions decreased after 1 day but increased again after 3 days of progesterone treatment. The results indicated that there is a reduction in the actual concentration of oestrogen receptors in both cytosolic and nuclear fractions after continuous oestrogen treatment. The antagonism by progesterone of the effects produced by oestrogen appears to be transitory in nature, at least in the rabbit uterus.

Prevalence of urinary incontinence in middle-aged women.

An anonymous questionnaire was used to interview 946 premenopausal women (age 29-52 years), previously either hysterectomized or laparoscopically sterilized, concerning disorders of the urinary tract. Of the 750 (79.3%) women that responded, 307 (40.9%) admitted to some degree of urinary disorder. The prevalence of urinary disorders was 170/415 (40.9%) for the women with a previous supravaginal or total hysterectomy and 137/335 (40.8%) for the women in the sterilization group. Of the responding women 85 (11.3%) experienced a urinary loss sufficient to necessitate the wearing of a sanitary napkin or change of underclothing several times a day.

Prognosis and long-term follow-up of a twin after antenatal death of the co-twin.

It is generally believed that among twin pregnancies with one fetal loss prior to delivery, the surviving twin has an increased rate of perinatal mortality and childhood morbidity (cerebral palsy and mental retardation). By using data from the National Medical Birth Registry of Sweden between 1973 and 1983, we identified 206 gestations with the death of at least one twin (in 36 pregnancies both twins died) prior to delivery. The original medical records were retrieved for study. The presence of childhood morbidity for 65 of 129 surviving (8 years of age or older) twins born between 1973 and 1980 was evaluated by a questionnaire sent to rehabilitation centers for disabled children, as well as to offices for the Provision of Care for the Mentally Retarded. Perinatal mortality for a twin after the antenatal death of the co-twin was considerable. Fifty percent of survivors died before 34 weeks' gestation, and 18.7% thereafter. At follow-up, 8 years or more after birth, three twins (4.6%) were handicapped. Our results indicate the need for careful monitoring of the surviving twin fetus after one twin has succumbed prenatally.

Myometrial norepinephrine in human pregnancy. Elevated levels in various disorders leading to cesarean section.

Myometrial norepinephrine was measured consecutively with high-performance liquid chromatography in women who delivered by cesarean section. The previously recorded marked reduction in tissue norepinephrine at the end of normal pregnancy was confirmed. When cesarean section was performed because of abruptio placentae/hemorrhage, impending asphyxia, dystocia or preeclampsia, the norepinephrine concentrations were six to ten times higher than in normal pregnancy. When an emergency cesarean section was carried out for premature breech presentation, transverse position of the fetus or prolapse of the umbilical cord (following an otherwise-normal pregnancy), the reduced norepinephrine values were not significantly different from those measured in a control group of women who underwent elective cesarean section. It is possible that the abnormally elevated levels of myometrial norepinephrine are part of the primary pathophysiologic condition associated with sympathetic overactivity, resulting in disturbed myometrial circulation and/or motor activity.

[Patient based care registries as a tool to follow up services]. / Individbaserade vårdregister en hjälp vid verksamhetsuppföljning.

The Federation of Swedish County Councils and six medical specialties are working together in a project aiming to support and stimulate the development of patient based case registers as a tool to follow up, evaluate, develop and manage medical units. The project is based on participation on the part of the medical professions in a process-oriented way. Each case register shall be based on the individual patient, and will integrate inpatient and outpatient care, all medical professions and important procedures. In hematology the project also seeks to merge case costing data with the patient based case registers in order to facilitate more comprehensive cost analysis and comparison. This episodic perspective is useful for providers per se as well as in discussions between purchasers and providers as a method for understanding and analyzing medical services. The six specialties are hematology, obstetrics and gynecology, ophthalmology, otorhinolaryngology, dermatology and sexually transmitted diseases, and lastly psychiatry.

Prognosis for twins with birth weight less than 1500 gm: the impact of cesarean section in relation to fetal presentation.

The purpose of this study of twins weighing less than 1500 gm was to evaluate the impact of cesarean section on intrapartum and neonatal mortality, as well as on cerebral palsy and mental retardation. National data held at the Medical Birth Registry was used for identification of cases. The original medical records were retrieved for 862 such twins born between 1973 and 1983. Twins with cerebral palsy and/or mental retardation born between 1973 and 1980 were identified by questionnaires to all rehabilitation centers for disabled children, offices for the Provision of Care for the Mentally Retarded, and to all local Boards of Education throughout Sweden. The analyses, including calculation of relative risk and 95% confidence interval, were performed after stratification for birth weight (250 gm classes) and period of delivery (1973 to 1976, 1977 to 1980, 1981 to 1983). The cesarean section rate increased from 7.7% (1973 to 1976), and 40.5% (1977 to 1980) to 68.9% (1981 to 1983). Concomitantly, intrapartum and neonatal mortality decreased markedly (51.7% to 29.1%) particularly for twin II but to a much lesser extent for twin I. The relative risk for intrapartum and neonatal mortality (vaginal/abdominal birth) did not increase significantly for twin I in vertex presentation (relative risk 2.0, 95% confidence limits 0.9 to 4.3), for twin I in breech presentation (relative risk 1.8, 95% confidence limits 0.7 to 4.3), for twin II in vertex presentation (relative risk 0.6, 95% confidence limits 0.2 to 1.6), or for twin II in breech presentation (relative risk 1.5, 95% confidence limits 0.7 to 3.0). The rate of cerebral palsy and/or mental retardation was 8.8% during 1973 to 1976 and 8.0 during 1977 to 1980 (chi 2 = 0.1, p greater than 0.05). For twins born in breech presentation the handicap rate in the first period (cesarean section rate 6.0%) was the same as in the second period (cesarean section rate 59.6%). The analysis failed to reveal any significant impact of abdominal birth on the fetal outcome for low-birth-weight twins, even when fetal presentation was taken into consideration.

Twin pregnancy and the effects of prophylactic leave of absence on pregnancy duration and birth weight.

The purpose of the study was to evaluate the effects of taking prophylactic leave of absence from work during a twin pregnancy. Pregnancy outcome for 78 women who were prescribed prophylactic leave of absence from work to prevent preterm delivery was compared with a group of 78 twin-pregnant controls who did not take prophylactic leave. Gestational duration and birth weight did not differ between the two groups. The results indicate that prophylactic leave of absence from work did not improve the outcome of a twin pregnancy.

Prognosis for twins discordant in birth weight of 1.0 kg or more: the impact of cesarean section.

The purpose of this population-based study on twins whose birth weight was discordant by 1.0 kg or more, was to evaluate the impact of abdominal delivery on the "corrected perinatal mortality" (fetal death prior to delivery being excluded), and also on childhood morbidity. Between 1973 and 1983, 277 such discordant twin pairs were identified in Sweden, using the Medical Birth Registry, Stockholm. The original medical records were retrieved for 267 pairs. The presence of childhood morbidity of 437 twins born between 1973 and 1980 was determined by means of questionnaires sent to rehabilitation centers for handicapped children, offices for the Provision of Care to the Mentally Retarded throughout Sweden, as well as to local Boards of Education. No association was found between corrected perinatal mortality figures and a more than 4-fold increase in cesarean section rate, from 11.4% during 1973-75 to 45.9% during 1980-83. The 10 perinatal deaths (1.9%) could be correlated with birth weight (9 small and 1 large twin; p = 0.01), but not to the mode of delivery of the smaller twins (6 born vaginally and 3 abdominally; p greater than 0.05). At follow-up, at the age of 8 years or more, 5 smaller and 4 larger twins had cerebral palsy and/or mental retardation; no correlation was found with mode of delivery. The results of this study show that perinatal death (twins with lethal malformation included) or residual major handicap occurred in one of ten pregnancies of twins with discordant birth weights. Abdominal delivery seemed to have little impact on either short or long-term outcome.

Discordant birthweight and late fetal death in like-sexed and unlike-sexed twin pairs: a population-based study.

OBJECTIVE: To study the relation between pregnancy loss (one or two fetal deaths in a pair) in twin pregnancy and gender (like-sexed and unlike-sexed pairs), discordant birthweight, and placentation. DESIGN: The type of placentation for gestations with pregnancy loss was studied, based on material retrieved from the original medical records, for a defined region comprising 20.0% of the total twin population. SUBJECTS AND SETTING: Four thousand one hundred and ninety-one unlike-sexed and 10,875 like-sexed twin pairs born in Sweden between 1973 and 1989, in most cases with a gestational duration 28 or more completed weeks. RESULTS: The relative risk (RR) for pregnancy loss in like-sexed pairs, compared with unlike-sexed ones, was 2.3 and the 95% confidence limits (CL) 1.7-3.1. Not until discordance exceeded 999 g did the pregnancy loss rate for unlike-sexed pairs increase significantly, compared with the (first) stratum with discordance less than 250 g (RR = 6.3; CL 3.5-11.3). For like-sexed twin pairs a higher pregnancy loss rate, compared with the first stratum, was seen already in the stratum with discordance 250-499 g (RR = 1.3; CL 1.0-1.8); a significant increase in pregnancy loss rate was found in all the three strata 500-749 g (RR = 2.1; CL 1.5-3.0), 750-999 g (RR = 3.5; CL 2.3-3.0), and 1000 g or more (RR = 10.9; CL 8.4-14.2), respectively. When calculating the discordance as a percentage of the weight of the larger twin, unlike-sexed pairs experienced a significant increase in pregnancy loss when discordance exceeded 40 to 50%. For like-sexed ones, the corresponding figures were 20 to 30%. In the 47 unlike-sexed pregnancies complicated by pregnancy loss, both twins died in two pregnancies (4.3%), whereas for like-sexed pairs the corresponding figures were 65/279 (23.3%). Of 47 gestations with pregnancy loss in a defined region, 32 were monochorionic (monozygous), nine were like-sexed dichorionic (monozygous or dizygous), and six were unlike-sexed (dizygous). CONCLUSIONS: Pregnancy loss was twice as high in like-sexed compared with unlike-sexed pairs, and only in like-sexed pairs was pregnancy loss strongly correlated to birthweight discordance. In twin pregnancies with one fetal death the risk for the surviving twin to succumb is five to six times higher in like-sexed compared with unlike-sexed pairs and is most probably related to monochorionicity.

Gestational duration and birth weight for twins related to fetal sex.

It has been postulated that male twin pregnancies, in contrast to male singleton pregnancies, differ in some distinctive biologic sense, leading to a shorter gestational duration and a lower individual birth weight than is the case in female twin pregnancies. To test this hypothesis in a relatively large dataset, information on gestational duration and birth weight for nearly all twins born in Sweden during a 4-year period (n = 3,472 twin pairs) was collected from the Medical Birth Registry, National Board of Health and Welfare. Included in the Medical Birth Registry are all pregnancies with a duration of at least 28 completed gestational weeks, or less if the newborns are alive at birth. Male-male pregnancies had a gestational duration similar to female-female pregnancies (median difference less than 2 days). The proportions of twins with a gestational age less than 36 weeks did not differ between male-male and female-female twin pregnancies (27.3 vs. 25.3%; chi 2 = 2.2, p greater than 0.05). Male-male pairs were heavier than female-female pairs (median difference 0.1 kg), and a significantly higher proportion of female-female twin pairs weighted less than 2,500 g (45.0 vs. 39.2%; chi 2 = 17.7, p less than 0.001). The results of this study in an unselected relatively large twin population seem to indicate that fetal sex does not influence gestational duration to any significant extent. Males are heavier than females indicating that the sex has a similar effect on birth weight in twin and in singleton pregnancy.

A birthweight-for-gestation standard based on 4737 twins born in Sweden between 1983 and 1985.

OBJECTIVE: To construct a birthweight-for-gestation chart based on a population-based material of twins born during a restricted period of time. MATERIAL AND METHODS: Nearly all live-born twins born in Sweden between 1983 and 1985, 4737 all told, were included. Excluded from the analysis were 4.7% of the twins that were not on record at the Medical Birth Registry, 1.8% that died before or during birth, and 8.8% that were without a recorded date of birth or only had information on gestational duration estimated from the first day of the last menstrual period. RESULTS: The standard deviation in birthweight was considerable in most gestational weeks; the range (+/- 2 SD) was 1000-3400 g even if exclusively twins (pregnancies) with estimated date of birth from ultrasound examination early in the second trimester were included. Intra-pair discordance increased with gestational duration, especially for unlike-sexed twins, to reach over 400 g at term. On average, boys weighed 92 g more than girls and twins to multiparae weighed 250 g more than twins to primiparae. Maternal age affected birthweight for twins to primiparae, but not to multiparae. CONCLUSION: Although the problems with secular trends in birthweight were avoided by using a population-based material during a restricted time period, and only twin pregnancies dated with ultrasound were included, the standard deviation in most gestational weeks was still considerable, reflecting the multiplicity of factors involved in determining the birthweight of twins.

The effects of maternal age, parity, and sex of the twins on twin perinatal mortality. A population based study.

The aim of this study on all twin births in Sweden between 1973 and 1985 was to evaluate the effect of maternal age, parity, and sex on twin perinatal mortality (PNM), by using national data held at the Medical Birth Registry, National Board of Health and Welfare, Stockholm. Zygosity in this study was estimated by the Hardy-Weinberg formula. In all, 22,374 twins were born; 972 (4.3%) of these died perinatally. The relative risk for perinatal death (after standardization for maternal age, parity, and like sex) decreased significantly during the study period, and reached its lowest value (0.3) in 1983. Maternal age was not associated with PNM, while women having their first delivery had a significantly higher PNM than the rest of the parturients. The MZ twinning rate increased from 0.36% during 1973-76, to 0.40% during 1977-81 and 0.44% during 1982-85 (trend analysis: chi 2 = 40.1, p less than 0.001). After stratification for year of delivery and birthweight, like-sexed twins had a significantly higher PNM than unlike-sexed twins (odds ratio, OR = 1.25, 95% confidence interval, CI = 1.02-1.54). Males had a significantly higher PNM than females in like-sexed pairs (OR = 1.39, 95% CI = 1.16-1.66), and in unlike-sexed pairs (OR = 1.46, 95% CI = 1.01-2.10). MZ twins had a significantly higher estimated PNM than DZ ones (OR = 1.31, 95% CI = 1.02-1.67).

No benefit from conservative management in nulliparous women with premature rupture of the membranes (PROM) at term. A randomized study.

OBJECTIVE: To compare maternal and fetal outcome in pregnancies with premature rupture of the membranes (PROM) at term with either early induction of labor or conservative management awaiting spontaneous labor. DESIGN: A prospective randomized trial. SETTING: The University Hospital of Lund, Sweden. SUBJECTS: Altogether 369 women with singleton pregnancy, cephalic presentation, gestational duration 36-41 weeks, were randomized either to induction of labor (n = 139) or conservative management up to 3 days (n = 138). Those eligible but not participating in the study totalled 92. MAIN OBSTETRIC MEASURES: Obstetric intervention rate (cesarean section or instrumental delivery) and short-term neonatal morbidity. RESULTS: No difference was found in the rate of obstetric intervention between the induction of labor group and the group with conservative management (12.2 vs. 18.8%; chi 2 = 2.3, p greater than 0.05). A slightly increased rate of neonatal infections was seen in the latter group (0.7 vs. 4.3%; chi 2 = 3.2, p less than 0.05). CONCLUSIONS: We found no benefit from conservative management for up to 3 days in women with PROM at term, compared with immediate induction of labor. There was no difference in the number of obstetric interventions during labor. The neonatal infectious morbidity was slightly higher in conservatively managed cases.

Twin delivery: how should the second twin be delivered?

In a series of 803 pairs of twins born between 1973 and 1982, 0.33% of second twins were delivered by cesarean section after vaginal delivery of the first twin. During the last year the frequency has increased to 7%, calling attention to the problem of declining obstetric skills and experience. This has caused us to update the routines of intrapartum management of twin gestations. In the present program only commonly available obstetric techniques are used. The potentially hazardous twin delivery is excluded from a trial of vaginal delivery. Hopefully, the program will help other obstetricians to decide in favor of vaginal delivery in selected twin gestations.

Management in second stage of labour in term twin delivery.

A simple program for management of term twin delivery in the second stage of labor is presented. Provided that given selection criteria are met, twins at term are delivered by the vaginal route.

Pregnancies with growth-retarded twins in breech-vertex presentation at increased risk for entanglement during delivery.

The purpose of this population based study on twins born in Sweden between 1961 and 1987 was to estimate the risk to the fetuses of becoming entangled during birth, and to identify those pregnancies with an increased risk for this rare complication. By using 3 separate questionnaires, 41 of 26,428 twin pregnancies with entanglement were identified. Twins in breech-vertex presentation (group A; 29 cases) were at significantly greater risk of entanglement (chi 2 = 168.3, p less than 0.001) than twins not in breech-vertex presentation (group B; 8 in vertex-vertex, 3 in breech-breech, and 1 in vertex-breech presentation). Known risk factors for entanglement in group A were intra-uterine growth retardation, a birth weight less than 2000 g, and antenatal fetal death. Intrapartum-neonatal mortality reached 38.9% in group A (median gestational week 36); and for group B, 8.3% (median gestational week 38). Entanglement during the study period occurred in 1 of 645 twin deliveries, on average. A vaginal delivery is proposed for women with twins in breech-vertex presentation, unless other risk factors leading to an increased risk for entanglement warrant abdominal delivery.