Effect on neonatal jaundice of oestrogens and progestogens taken before and after conception

Perinatal events and neonatal morbidity: an analysis of 5380 cases

The associations between perinatal events and neonatal morbidity were examined in a regional population of 5 380 newborns weighing 500 g or more. Perinatal mortality was 6.9%, and neonatal mortality was 3.0%. The low birth weight (less than 2500 g) rate was 3.8%. The incidence of prematurity (gestational age less than 37 weeks) was 6.6%. Respiratory distress syndrome was found in 0.9%, nonhaemolytic hyperbilirubinaemia in 16.5%, hypoglycaemia in 0.5%, septic infection in 0.8%, asphyxia in 4.0%, intracerebral haemorrhage in 0.3%, and cerebral symptoms in 0.7%. Maternal toxaemia, multiple pregnancy and maternal short stature were associated with spontaneous prematurity and a birthweight below the 10th percentile. Prematurity was associated with respiratory distress syndrome, hyperbilirubinaemia, hypoglycaemia, infection, low Apgar scores, asphyxia and intracerebral haemorrhage. Placental complications were associated with spontaneous prematurity, low Apgar scores and asphyxia. Premature rupture of the membranes was associated with spontaneous prematurity, infection, low Apgar scores and asphyxia.

The effect of oxytocin in induced labour on neonatal jaundice

A prospective study in 180 mothers and babies examined the effects of oxytocin in induced labour on plasma bilirubin levels in cord blood, as well as on the incidence of neonatal jaundice. Raised plasma bilirubin levels in cord blood, probably enhanced by breakdown of fetal red cells, appeared to be a dose dependent effect of oxytocin. Commensurate with this was the finding that a larger proportion of babies in the induced group manifested a greater severity of jaundice.

Factors affecting neonatal jaundice

Plasma bilirubin was estimated on 690 term infants on about the 6th day of life. Perinatal factors were recorded and the results analysed. Hyperbilirubinaemia was defined as a level greater than 205 micromol/1 (12 mg/100 ml) and this was present in 20% of cases. Three factors--epidural analgesia, breast feeding, and poor weight recovery--showed highly significant associations with jaundice. The relative importance of these is discussed and compared with recent reports. Induction of labour, for reasons other than postmaturity, and a gestational age less than 39 weeks showed a slightly increased incidence of jaundice. There was no correlation with other factors tested including oxytocic drug administration. Despite the high incidence (20%) of hyperbilirubinaemia, only 2.5% infants needed treatment and none required exchange transfusion. Radical changes in obstetric management or infant feeding are not indicated.

Influence of simultaneous low amniotomy and oxytocin infusion and other maternal factors on neonatal jaundice: a prospective study

In a prospective study of 196 consecutive single births a significant increase in serum bilirubin concentrations was found in infants born after low amniotomy induction and oxytocin infusion compared with those born spontaneously. This relationship was not dose-dependent and may have been associated with artificial interruption of pregnancy rather than the oxytocin itself. Infants delivered after spontaneous labour accelerated by oxytocin showed no such increase. The hormonal surge at the spontaneous onset of labour may affect fetal enzyme induction, but other factors, such as methods of infant feeding and oral contraceptive use, were found not to be significant.

Factors affecting the increasing incidence of severe non-haemolytic neonatal jaundice

Neonatal hyperbilirubinaemia is increasing in frequency. In view of conflicting evidence about the possible causes, retrospective analyses have been carried out among babies born during six months of 1974. Preliminary analysis confirmed the over-riding importance of preterm birth (before 37 weeks), but only one of 17 such cases could be attributed to ill-judged artificial induction of labor. For the main analysis, the incidence of eight possibly relevant antecedent factors was compared in 46 cases of hyperbilirubinaemia (unconjugated bilirubin more than 15 mg per 100 ml in term babies and more than 13 mg per 100 ml in some preterm babies) and in 92 controls matched for sex and gestational age. Induction of labour by "primary" oxytocin infusion and artificial rupture of the membranes was very significantly more common in the index cases (p less than 0-01), but there was no difference in the incidence of "secondary" oxytocin, used to accelerate spontaneous labour. Evidence of uterin unresponsiveness suggests that the natural onset of labour was being anticipated by at least some days in many of the index cases and this could prevent the natural "priming" of the fetal enzyme systems. An excess of epidural analgesia in the mothers of the index cases was probably due to its association with the need for pain relief during "primary" oxytocin infusions. The higher incidence of postnatal weight loss in the index cases presumably contributed to the hyperbilirubinaemia.

Use of oxytocin and incidence of neonatal jaundice

A retrospective controlled study using data from the Cardiff Births Survey examined a possible relation between oxytocin administration to induce or accelerate labour and the subsequent development of neonatal jaundice. Among 10 591 infants born in Cardiff between 1970 and 1972 the incidence of neonatal jaundice was higher in infants born after oxytocin administration than among others. Analysis by gestational age at delivery, birth weight, Apgar score, length of labour, sedative and analgesic therapy during labour, and suppression of lactation showed that this association held within all these categories except among small immature infants, who are at high risk of jaundice in any case.

Neonatal jaundice and glucose-6-phosphate dehydrogenase deficiency in Papua New Guinea

Of 50 jaundiced neonatal patients studied at the Port Moresby General Hospital, 11 (22%) were found to be glucose-6-phosphate dehydrogenase-deficient. No apparent exogenous precipitating causes for the jaundice were noted. Serum bilirubin levels exceeded 20 mg/100 ml in seven of these glucose-6-phosphate dehydrogenase-deficient infants, and exchange transfusions were required for three subjects. Glucose-6-phosphate dehydrogenase deficiency must be considered in the differential diagnosis of neonatal jaundice in Papua New Guinea.