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Ralph McGinnis, Valgerdur Steinthorsdottir, Linda Morgan and colleagues perform a genome-wide association study in the offspring of preeclampsia pregnancies and identify variants in the fetal genome near FLT1 that are associated with risk of preeclampsia. FLT1 is known to encode an isoform of placental origin implicated in the pathology of preeclampsia, providing biological support for the association of this locus with preeclampsia risk. Preeclampsia, which affects approximately 5% of pregnancies, is a leading cause of maternal and perinatal death1. The causes of preeclampsia remain unclear, but there is evidence for inherited susceptibility2. Genome-wide association studies (GWAS) have not identified maternal sequence variants of genome-wide significance that replicate in independent data sets3,4. We report the first GWAS of offspring from preeclamptic pregnancies and discovery of the first genome-wide significant susceptibility locus (rs4769613; P = 5.4 × 10−11) in 4,380 cases and 310,238 controls. This locus is near the FLT1 gene encoding Fms-like tyrosine kinase 1, providing biological support, as a placental isoform of this protein (sFlt-1) is implicated in the pathology of preeclampsia5. The association was strongest in offspring from pregnancies in which preeclampsia developed during late gestation and offspring birth weights exceeded the tenth centile. An additional nearby variant, rs12050029, associated with preeclampsia independently of rs4769613. The newly discovered locus may enhance understanding of the pathophysiology of preeclampsia and its subtypes.

A retrospective study was made to determine the incidence of pregnancy-induced hypertension (PIH, pre-eclampsia) in Iceland. One-fourth of all births in Iceland in 1985 were selected from the national birth registry files by random number allocation, a total of 904 women. Maternity records were found in 97.9% of the cases. The criteria used to define PIH were met in 17.4% of the women. There were 146 (16.5%) with mild PIH (blood pressure of greater than or equal to 140/90 mmHg with or without proteinuria after the 20th gestational week). Eight (0.9%) had severe PIH (blood pressure of greater than or equal to 160/110 mmHg with or without proteinuria after the 20th gestational week). Primigravid women formed one-third of the group and of these 20.9% had PIH compared with 15.4% of the parous women. The incidence in parous women was higher than usually reported.

A double-blind controlled trial of intracervical prostaglandin E2 gel was carried out in patients with an unripe cervix. Half of the treated group, compared to 8.6% of the controls became established in labor before planned amniotomy. There was no significant improvement in the state of the cervix in the remaining patients and the outcome of labor was not improved in the treated group in terms of fetal distress or cesarean section.

In a retrospective study of all perinatal and neonatal deaths in Iceland in 1976-85, the circumstances surrounding each death were carefully evaluated to assess the quality of care given and to identify cases of suboptimal care. In 1976-80, 87 or 35% of peri- and neonatal deaths were associated with suboptimal care and 46 or 29% of peri- and neonatal deaths in 1981-85. Most of the infants weighed more than 1500 g. Suboptimal care was most commonly seen in conjunction with antenatal care in both five-year periods, with a 25% (N.S.) reduction of cases in 1981-85. Suboptimal intrapartum care was significantly reduced (p less than 0.05) and there was a substantial reduction (62%), although not significant (0.1 greater than p greater than 0.05), of suboptimal neonatal care between the two periods. A few cases were attributable to maternal decisions taken against medical advice, most of them in the latter period. Perinatal care improved during the study period. The task of further lowering perinatal mortality rates depends on vigilance to abnormal findings in routine antenatal care.

The accuracy of ultrasonic measurements of intra-amniotic volume using a parallel planimetric area method was assessed in 18 women by comparison against different measures of the same volume space. In nine patients undergoing second-trimester termination of pregnancy amniotic fluid volume was measured using a dye dilution method and fetal volume was measured by either water displacement or calculated from fetal weight. The estimated intra-amniotic volume by this method was not significantly different from the ultrasonic measurement. In one patient who had a hysterotomy, fetal and amniotic fluid volumes showed a difference of 1.01% between ultrasonically-measured and actual intra-amniotic volume. In eight patients studied in the third trimester the mean difference between ultrasonic and estimated intra-amniotic volume at delivery was 6.2%.

A comparison of a prolate ellipsoid method and a parallel planimetric area method for measuring volumes with ultrasound was made using phantom models of water-filled balloons scanned under set conditions. Correlation with actual volumes was significantly better with the parallel planimetric area method (p < 0.02) with 93.3% of parallel planimetric area measurements being within 5% of the actual volume compared with only 33.4% of measurements obtained with the prolate ellipsoid method. For uterine volume measurements, a parallel planimetric area method is the more suitable.

Anthropometric standards for weight, length and head circumference of Icelandic infants at birth are presented. The material concerning weight and crown-heel length consisted of 43364 newborns, the total number of infants born in 1972-1981. The standards for head circumference were based on 28978 infants born in 1975-1981. Multiple births and stillbirths were excluded from the material, leaving single livebirths with an estimated length of gestation of 28-44 weeks. No further exclusions were made. The material was compared with previous standards used in Iceland as well as with other studies of all single livebirths in geographically defined populations. Standards for crown-heel length and head circumference were compared with other studies based on more limited and selective materials. The differences between these studies emphasize the need for an international agreement on the methodology for measurement and recording of infant growth during the perinatal period.