Search

Background. In vitro fertilization, sometimes involving the cryopreservation of human embryos, has become a routine procedure for the treatment of infertility. Even though there are embryos available for transfer in about 85 percent of the treatment cycles, the rate of pregnancy rarely exceeds 25 percent per cycle. We designed this study to investigate two questions: Does this high rate of failure result from inadequate technique, or does it simply reflect the maximal potential of a cohort of aspirated eggs to produce a pregnancy? And to what extent does cryopreservation affect the capacity for implantation of embryos? Methods. The study was conducted among patients enrolled in an egg-donation program. Aspirated eggs from a given cohort were distributed to the donor herself and a few recipients. The recipients were prepared by a standard protocol of hormone replacement and were assigned at random to the transfer of either fresh or frozen and thawed embryos. The donors received only fresh embryos....

The death of one fetus in a twin pregnancy can affect both the mother and the cotwin. Thirty women with twin pregnancies in whom the death of one fetus was diagnosed during the second half of pregnancy and a matched group of 30 women with uncomplicated twin pregnancies were investigated. The mean gestational age at delivery for the study and control groups was 32.0 +/- 5.0 (mean +/- SD) weeks and 32.8 +/- 3.9, respectively. Twelve pregnancies (40%) were monochorionic. In 15 (50%) the diagnosis was made during active labor. The cesarean delivery rate was higher in the study group than in the control group (18 vs. 11, chi 2 = 5.43, P.02). The mean neonatal weight was similar in both groups (1,586 +/- 725 g vs. 1,543 +/- 691 g). The subgroup of neonates (n = 15) whose cotwins were diagnosed as dead during labor had higher birth weight as compared to the neonates (n = 15) in whom the diagnosis was made prior to delivery and were managed expectantly (1,829 +/- 859 vs. 1,346 +/- 474 g, P.01). The week of delivery was similar in both subgroups. Neonatal mortality was 30% and 26.6%, while neonatal morbidity was 26.6% and 21.7%, respectively (NS). All the cases of neonatal mortality were in the subgroup of twins in which the diagnosis of in utero death was made before 32 weeks' gestation. The death of one fetus from a twin pregnancy did not significantly jeopardize maternal health, and the neonatal outcome in the remaining twins was primarily a function of gestational age.(ABSTRACT TRUNCATED AT 250 WORDS)

Objective--To study the effect of birth weight and body weight on blood pressure in late adolescence. Design--Analysis of data on weight, height, and blood pressure at age 17 of subjects from the Jerusalem perinatal study, according to their birth weight. Data for men and women were analysed separately. Setting--Jerusalem, Israel. Subjects--32,580 subjects (19,734 men and 12,846 women) born in the three major hospitals in Jerusalem during 1964-71 and subsequently drafted in to the army. MAIN OUTCOME MEASURES--Correlations between birth weight and blood pressure at age 17 and weight and height at age 17 and blood pressure. Results--Diastolic and systolic blood pressures were associated with birth weight in both young men and young women, but the correlation coefficients were low. A high body weight at age 17 (greater than 66 kg for women, greater than 75 kg for men) rather than a low birth weight (less than 2500 g) was linked with higher systolic and diastolic blood pressures in both men and women (p less than 0.01). Conclusions--Intrauterine environment, as reflected by birth weight, has little effect on blood pressure in young men and women. Modification of factors which lead to excess weight during adolescence may have a major role in preventing hypertension in adults.