[Within the limits of viability: the dilemma of the obstetrician. A 5-year experience at a perinatal care center]. / En los límites de la viabilidad: el dilema del obstetra. Experiencia de cinco años en un Centro de Atención Perinatal.

The study was performed in order to establish the obstetric factors that influence survival of newborns whose birth weight is under 1000 g. All medical records of babies with such birth weight, born alive at the Instituto Nacional de Perinatología in Mexico City during the period from 1991 to 1996 were revised. Babies with congenital malformations, cromomosomopathies or those who after birth were referred to another medical center were excluded. Survival status was used to form two study groups: those who were discharged alive and those who died during their hospital stay. Different obstetric conditions on management were compared between these two groups. Statistical Analysis was performed through t-test, chi square or exact Fisher's test. Two hundred and ninety two cases were included out of 294. Sixty nine (25.4%) survived while 203 (74.6%) died during their hospitalization. Several obstetric conditions were found to have statistical differences between survivors (S) and non survivors (NS): cervical dilatation on admittance to hospital (1.6 cm among S and 2.7 among NS), cervical dilatation prior to resolution (3.3 cm S vs 4.9 cm NS), gestational age (28.3 vs 27 weeks). Newborn conditions also showed significant statistical differences as in birth weight (867.1 vs 795.5 g), 1 minute Apgar (4.1 vs 2.5), and 5 min Apgar (6.9 vs 5). Use of antepartum steroids showed a striking difference between groups while duration of labor, usage of oxitocin and way of delivery showed no statistical differences. Gestational age (over 28 weeks), birth weight (above 867 g) and the use of antepartum steroids are of extreme importance in the survival status of babies born weighting less than 1000 g.

[Abdominal pregnancy, institutional experience]. / Embarazo abdominal experiencia institucional.

Abdominal pregnancy is a rare entity, which has been classified as primary or secondary by Studiford criteria. A retrospective study, between January 1989 and December 1994, realized at Instituto Nacional de Perinatología, found 35,080 pregnancies, from which 149 happened to be ectopic, and 6 of them were abdominal. All patients belonged to a low income society class, age between 24 and 35 years, and average of gestations in 2.6. Gestational age varied from 15 weeks to 32.2 weeks having only one delivery at term with satisfactory postnatal evolution. One patient had a recurrent abdominal pregnancy, with genital Tb as a conditional factor. Time of hospitalization varied from 4 to 5 days, and no further patient complications were reported. Fetal loss was estimated in 83.4%. Abdominal pregnancy is often the sequence of a tubarian ectopic pregnancy an when present, it has a very high maternal mortality reported in world literature, not found in this study. The stated frequency of abdominal pregnancy is from 1 of each 3372, up to 1 in every 10,200 deliveries, reporting in the study 1 abdominal pregnancy in 5846 deliveries. The study had two characteristic entities one, the recurrence and two, the delivery at term of one newborn. Abdominal pregnancy accounts for 4% of all ectopic pregnancies. Clinical findings in abdominal pregnancies are pain, transvaginal bleeding and amenorrea, being the cardinal signs of ectopic pregnancy.