"Macrosomic" twinning: a study of growth-promoted twins

We evaluated 56 twin pregnancies representing the tenth decile of the mean twin birth weight distribution to investigate whether larger twins face the same increased perinatal risk as do macrosomic singletons. Compared with pregnancies in the ninth decile, no significant difference was found between the means of maternal age, parity, and gestational age; between the rates of presentation combinations and cesareans; or between the neonatal sex ratios. However, the incidence of growth-discordant pairs was significantly higher in the heavier group (P = .034). Compared with the general twin population, the tenth-decile group contained significantly fewer primiparas (P = .0023). Maternal obesity and diabetes were infrequent and could not explain the increased birth weight. The neonatal outcome was excellent. Although the comparison revealed insignificant differences, it is possible that the combination of higher parity, malpresentation rate, and male-to-female ratio may be operative in the genesis of large twins.

What it takes to validate behavioral toxicology tests: a belated commentary on the Collaborative Behavioral Teratology Study

"Design Considerations in Screening for Behavioral Teratogens: Results of the Collaborative Behavioral Teratology Study" (CBTS) was an important conference whose proceedings were published in entirety in Neurobehavioral Toxicology and Teratology (7:532-822; 1985). The proceedings advocate that mandatory "behavioral teratology" testing be made part of regulations governing approval of new drugs and chemicals. This conclusion is unjustified either by the CBTS proceedings or by the present status of "behavioral teratology." First, there is little basis for accepting the validity of testing in developmental psychopharmacology, since so few agents acknowledged to lack the presumed toxic effects are explicitly identified and systematically tested. Second, findings from the CBTS itself can be construed as having indicated poor reliability: Amphetamine, the only drug examined in the CBTS, was selected for study expressly because of prior positive data, yet the study found it to be inactive. Third, the presumed "sensitivity" of behavioral measures is shown to be irrelevant. Fourth, and perhaps most important, the CBTS does not consider the public health risks of mandating nonvalid procedures within regulations. Drugs that are crucial both in therapy as scientific tools may not have been developed had regulations now advocated been in place at the time of their development.

The effect of cervical cerclage on the course of labor

Although it is generally believed that patients with previous cervical cerclage have abnormal labor patterns, there is little evidence to support this belief. We analyzed the pattern of cervical dilatation during labor in 114 women with cervical cerclage by the McDonald procedure who delivered vaginally at term and compared them with 150 normal laboring women. Similar patterns of cervical dilatation were found in both groups and there was no case of cervical dystocia, a commonly cited complication of cervical cerclage.

Maternal and fetal digoxin-like immunoreactive factor in elective cesarean sections and spontaneous vaginal delivery

The effect of mode of delivery on maternal and newborn plasma levels of total digoxin-like immunoreactive factor was evaluated. 32 healthy at term parturients with normal fetuses were studied. The cord blood level of digoxin-like immunoreactive factor of the 16 vaginally delivered infants was significantly higher than in the 16 matched controlled newborns delivered by an elective Cesarean section (1381 +/- 334 versus 1104 +/- 338 pg/ml, p less than 0.02). No differences were found between the maternal venous blood levels of digoxin-like immunoreactive factor of both study groups. The cord blood levels of this factor in the vaginal as well as the Cesarean section groups were significantly higher than the concentration in the corresponding maternal blood (p less than 0.001 and p less than 0.01, respectively). It is suggested that the changes in digoxin-like immunoreactive factor in the cord blood may reflect the stress of vaginal delivery on the fetus.

Birth weight discordancy in male-first and female-first pairs of unlike-sexed twins

We studied 153 consecutive twin pairs of unlike sex. Comparison of 71 male-female pairs with 82 female-male pairs showed similar mean twin birth weight and rate of discordance. However, males were significantly heavier (p less than 0.04) compared with females in the male-first but not in the female-first combination. The rate of female discordance was significantly higher compared with male discordance in both fetal sex combinations. It is concluded that females of unlike-sexed pairs are at greater risk to be growth discordant. Fetal sex, therefore, should be included as one of several factors that produce divergent twin growth.

Sonographic growth measurements in triplet pregnancies

Sonographic growth curves of biparietal diameter (BPD), head circumference, abdominal circumference, head circumference/abdominal circumference ratio, and femur length were generated from 24 uncomplicated, concordant triplet pregnancies. These were compared with the standard curves derived for singletons used in our medical center. Slowing of BPD, head circumference, and abdominal circumference growth was noted in triplets from the 28th week of gestation, whereas the head circumference/abdominal circumference ratio was similar to that of singletons. Femur growth was parallel to that of singletons, although on the low margin of the two standard deviations. We conclude that the growth patterns of triplets are different from those of singletons. We suggest that femur length derived for singletons may be suitable for the follow-up of triplets. However, when growth retardation is suspected, the growth curves presented herein may be used to identify the growth-retarded fetus.

Air embolism following intra-uterine hypertonic saline instillation: treatment in a high-pressure chamber; a case report

Air embolism was encountered in a patient following induced abortion by means of intra-amniotic hypertonic saline instillation. The only symptom present was isolated cortical blindness. The patient was treated in a high-pressure chamber and a nearly complete recovery was achieved.

Survival and long-term outcome of infants delivered at 24 to 28 weeks' gestation, by method of delivery and fetal presentation

Significant advances in perinatal intensive care and the increased chances of neonatal survival that have evolved in the last decade have posed moral and medicolegal questions for obstetricians that are as yet unanswered. Aggressive delivery management and major interventions for infants who were not long ago considered to be nonviable have become increasingly common. On the other hand, reports of high incidence of handicaps in the survivors cause great concern and add to the dilemma facing obstetricians. In this study, survival and long-term morbidity in 169 infants delivered at 24 to 28 weeks' gestation have been analyzed according to method of delivery and fetal presentation. At 24 to 25 weeks, survival was extremely low (10.5%) while major handicap rate was very high (42.9%). Infants born at 26 to 28 weeks' gestation had a considerably higher survival potential (42% to 74%), with an incidence of major handicap of less than 10%. At 26 to 28 weeks, abdominal delivery did not alter survival prospects of vertex-presenting infants; however, it improved survival of breech-presenting infants (70.0% compared with 22.2%) and showed a trend toward a lower handicap rate in the survivors.

Interstitial pregnancy: a diagnostic challenge

A case report which illustrates the clinical problems and sonographic difficulties that accompany the diagnosis of interstitial pregnancy are reported. Non-specific clinical symptoms and normal sonographic findings do not always preclude interstitial pregnancy.

Digoxin-like immunoreactive factor in twin and pregnancy-associated hypertensive pregnancies

The objective of this study was to measure maternal total digoxin-like immunoreactive factor levels in singleton pregnancies with or without hypertension and in twin pregnancies. Plasma digoxin-like immunoreactive factor was measured in 113 third-trimester patients: 51 normotensives, 20 preeclamptics, 19 with latent or chronic hypertension, and 23 with twin pregnancies. The concentration of total digoxin-like immunoreactive factor in the twin gestations (1143 +/- 249 pg/mL) was significantly higher than that in either the normotensive pregnancies (890 +/- 161 pg/mL) (P less than .001) or in the hypertensive pregnancies (903 +/- 256 pg/mL) (P less than .01). However, there were no significant differences in digoxin-like immunoreactive factor levels between the normotensive and hypertensive groups. A trend of higher, although not statistically significant, levels of digoxin-like immunoreactive factor was noted in the chronic hypertensive group as compared with the preeclamptic patients (957 +/- 212 versus 852 +/- 288 pg/mL). We therefore conclude that digoxin-like immunoreactive factor does not contribute significantly to the pathogenesis or prediction of preeclampsia. The increased amount of digoxin-like immunoreactive factor in twin pregnancies may reflect a contribution from multifetal origin, or might be a physiologic adaptive mechanism allowing higher cardiac output by a possible cardiotropic effect.

The influence of increased seismic activity on pregnancy outcome

The influence of increased seismic activity on pregnancy outcome was evaluated. A significant increase in delivery rate was noted during the 48 hours following an earthquake on all instances. In two out of five events, a significant increase in premature delivery rate was noted (p less than 0.05). Possible signs of fetal distress in utero were documented following these events.

A novel class of "GABAergic" agents: 1-aryl-3-(aminoalkylidene)oxindoles

Antagonism of mercaptopropionic acid (MPA) induced convulsions, reflecting a GABAergic mechanism, was observed in a series of 1-aryl-3-(aminoalkylidene)oxindoles. Optimal MPA antagonism was associated with 3-halo, 3-alkyl, and/or 4-alkoxy substituents in the pendant aryl ring and with (dimethylamino)methylene, 1-(dimethylamino)-ethylidene and N-methyl-2-pyrrolidinylidene side chains. The precise mechanism of action of these agents is unclear at this time; however, they are not GABA mimics and they do not affect GABA levels. Like other GABAergic agents, these compounds are potent enhancers of benzodiazepine binding and they antagonize cyclic GMP elevations induced by isoniazid. Compounds from this series may therefore have potential therapeutic utility as anticonvulsants or anxiolytics.

Fetal resuscitation with ritodrine during maternal seizures in labor. A case report

Uterine hypertonia with severe fetal distress occurred during maternal seizures in labor. The administration of ritodrine resulted in quick relaxation of the uterus and recovery of the compromised fetus.

Low birthweight breech infant: short-term and long-term outcome by method of delivery

The effect of the delivery method on the short-term and long-term morbidity and mortality of the very low birthweight breech-presenting infants was evaluated. Although some previous studies question the benefit of cesarean section for the premature breech infants, the mortality rate and the incidence of birth injuries were significantly lower in the abdominally delivered group than in those delivered vaginally. The long-term follow-up clearly demonstrates that the vaginally delivered infants had a substantially higher incidence of cerebral palsy, visual damage, deafness, and severe developmental delay. It is concluded that cesarean section may be the preferred delivery method for the breech-presenting infants weighing 1000 to 1999 gm, offering a better quality of life.

Single-dose cefazolin prophylaxis for cesarean section

In a prospective, randomized trial, the efficacy of a single-dose, first-generation, long-acting cephalosporin was compared with a three-dose regimen in a group of 100 women undergoing cesarean section who were at high risk for postoperative febrile morbidity. Fifty women received a single 1 gm intravenous dose of cefazolin and 50 received 1 gm of the drug followed by two additional doses, 8 hours apart, to complete a three-dose regimen. Another 50 women, considered to be at low risk for postoperative febrile morbidity, were not given antibiotic prophylaxis. Outcomes of febrile morbidity (18% vs 12%) and particularly morbidity caused by endometritis (6% vs 8%, respectively) were similar for single-dose and three-dose groups. In the untreated low-risk group there were no cases of endometritis and the febrile morbidity was comparable to that of the prophylactically treated groups (14% vs 15%). Single-dose cefazolin prophylaxis appears to be comparable to multidose prophylaxis in reducing febrile morbidity after cesarean section.

Antimuscarinic effects of (R)- and (S)- oxyphencyclimine hydrochloride

The (R)-(+)- and (S)-(-)-enantiomers of the anticholinergic compound, oxyphencyclimine, were synthesized from (R)-(-)- and (S)-(+)-2-cyclohexyl-2-hydroxy-2-phenylethanoic acid, respectively. The potencies of the enantiomers were compared using a cholinergic receptor binding assay. The (R)-(+)-enantiomer inhibited binding 29 times more potently than the (S)-(-)-enantiomer.

Uniform presentation of data concerning cesarean sections

Many studies concerning the various aspects of cesarean section have recently appeared in the literature. The important issues are the changing indications for the operation and the different management protocols in trial of labor following a previous cesarean section. As the different authors use different ways of presenting their results, comparison of these studies is a complex matter and the conclusions are sometimes misleading. It is proposed that the data presented should be more uniformly used, according to the principles presented in this study.

Acute polyhydramnios recurrent in four pregnancies. A case report

Acute idiopathic polyhydramnios recurred in four pregnancies. Laboratory and ultrasonographic examinations did not reveal the underlying pathology, and no anomalies were found in the infants.

Neuroleptics from the 4a,9b-cis- and 4a,9b-trans-2,3,4,4a,5,9b-hexahydro-1H-pyrido[4,3-b]indole series. 2

Compounds derived from 4a,9b-trans-2,3,4,4a,5,9b-hexahydro-1H-pyrido[4, 3-b]indole are consistently efficacious in displacing [3H]spiroperidol from striatal dopamine receptors in vitro. Derivatives bearing substituents at position 2, particularly those derived from butyrophenone moieties, are exceptionally potent in vivo. Compounds from the corresponding 4a,9b-cis series are substantially less potent in both in vivo and in vitro assays of neuroleptic activity. Although the cis and trans derivatives have, in some conformations, similar basic nitrogen atom to aromatic ring separations of about 5.1 A, the distance at which the basic nitrogen atom lies above or below the plane of the aromatic ring differs substantially between the two series. Consideration of these results in terms of this and earlier work indicates that the out-of-plane distance for the basic nitrogen in neuroleptic molecules may range from about 0 to about 0.90 A but may be optimized at about 0.55 A.