Benefits of introducing universal umbilical cord blood gas and lactate analysis into an obstetric unit.

BACKGROUND: Current evidence suggests that umbilical arterial pH analysis provides the most sensitive reflection of birth asphyxia. However, there's debate whether umbilical cord blood gas analysis (UC-BGA) should be conducted on some or all deliveries. AIM: The aim of this study was to evaluate the impact of introducing universal UC-BGA at delivery on perinatal outcome. METHODS: An observational study of all deliveries > or =20 weeks' gestation at a tertiary obstetric unit between January 2003 and December 2006. Paired UC-BGA was performed on 97% of deliveries (n = 19,646). Univariate and adjusted analysis assessed inter-year UC-BGA differences and the likelihood of metabolic acidosis and nursery admission. RESULTS: There was a progressive improvement in umbilical artery pH, pO(2), pCO(2), base excess and lactate values in univariate and adjusted analyses (P < 0.001). There was a significant reduction in the newborns with an arterial pH <7.10 (OR = 0.71; 95%CI 0.53-0.95) and lactate >6.1 mmol/L (OR = 0.37; 95%CI 0.30-0.46). Utilising population specific 5th and 95th percentiles, there was a reduction in newborns with arterial pH less than 5th percentile (pH 7.12; OR = 0.75; 95%CI 0.59-0.96) and lactate levels greater than 95th percentile (6.7 mmol/L; OR = 0.37; 95%CI 0.29-0.49). There was a reduction in term (OR = 0.65; 95%CI 0.54-0.78), and overall (OR = 0.75; 95%CI 0.64-0.87) nursery admissions. These improved perinatal outcomes were independent of intervention rates. CONCLUSIONS: These data suggest that introduction of universal UC-BGA may result in improved perinatal outcomes, which were observed to be independent of obstetric intervention. We suggest that these improvements might be attributed to provision of biochemical data relating to fetal acid-base status at delivery influencing intrapartum care in subsequent cases.

Disrupted secretory activation of the mammary gland after antenatal glucocorticoid treatment in sheep.

Antenatal glucocorticoids are administered to women at risk of preterm delivery to prevent neonatal respiratory morbidity. The effects of exogenous glucocorticoids on the development of lactation are unknown. This study investigated the effects of a single dose of antenatal glucocorticoids on secretory activation in sheep before and after parturition. Pregnant ewes (N=36) were randomised to receive either medroxyprogesterone acetate (MPA) at 118 days of pregnancy and betamethasone at 125 days (BETA group), MPA at 118 days and saline at 125 days (MPA group) or saline at 118 and 125 days (SALINE group). The concentration of lactose, progesterone, cortisol and prolactin in maternal plasma was measured during pregnancy. After term parturition, the concentration of lactose in milk and maternal plasma was measured daily for 5 days. Lambs were weighed at birth and at 5 days of age; milk volume was measured on day 5. The concentration of lactose in maternal plasma increased significantly after betamethasone administration, corresponding to a fall in plasma progesterone. No changes in lactose were observed in MPA or SALINE ewes. Transient decreases in cortisol and increases in prolactin were observed in the BETA group, but not in either the MPA or SALINE group. After parturition, BETA ewes experienced reduced milk yield and lamb weight gain, and delayed increases in milk lactose levels compared with MPA and saline controls. This study demonstrated that, in sheep, antenatal glucocorticoid administration disrupted secretory activation, causing precocious mammary secretion before parturition and compromising postpartum milk production and lamb growth.

Preterm birth aetiology 2004-2008. Maternal factors associated with three phenotypes: spontaneous preterm labour, preterm pre-labour rupture of membranes and medically indicated preterm birth.

OBJECTIVES: To (1) investigate the current distribution of PTB phenotypes; (2) identify factors associated with spontaneous preterm labour (SPTL), PPROM, and indicated PTB; (3) investigate the relationship of gestational age (ga) with each PTB phenotype. METHODS: Retrospective review of all live, singleton births 23(+0) to 36(+6) weeks ga at an obstetric referral centre 2004-2008. RESULTS: A total of 4,522 PTBs were included (SPTL 31.7%, PPROM 27.4%, indicated 40.8%). PTB phenotype distribution differed between ga groups (<27 weeks: SPTL 45%, PPROM 32%, indicated 23%; 27-33 weeks: SPTL 30%, PPROM 32%, indicated 39%; 34-36 weeks: SPTL 32%, PPROM 24%, indicated 44%, p < 0.001). Between 34-36 weeks', demographic factors were significantly different between PTB phenotypes (age ≥35: SPTL 13.8%, PPROM 15.4%, indicated 21.6%; Caucasian ethnicity: SPTL 61.6%, PPROM 69.0%, indicated 70.2%; Assisted Reproductive Technology (ART): SPTL 2.8%, PPROM 1.9%, indicated 9.3%; all p < 0.001). Between 27-33 weeks' PTB phenotype was associated with smoking (SPTL 24.9%, PPROM 29.3%, indicated 20.2%; p = 0.002) and ART (SPTL 2.3%, PPROM 1.6%, indicated 5.0%; p = 0.002). Demographic factors were not associated with PTB phenotype at 23-26 weeks. CONCLUSIONS: The increase in PTB rates may be explained by medical indications at late preterm gestations, primarily in older, Caucasian women requiring fertility assistance. Interventions to reduce the rate of PTB need to be targeted to this high-risk population.

Accurate prediction of hypoxic-ischaemic encephalopathy at delivery: a cohort study.

OBJECTIVE: Hypoxic-ischaemic encephalopathy (HIE) is a major acute neurologic manifestation of perinatal asphyxia associated with significant mortality and morbidity. The study aimed to develop a simple, accurate method of predicting HIE at delivery. METHODS: Between January 2003 and December 2009, all HIE cases were identified from the 38,404 deliveries at a single tertiary centre. Receiver operating curve (ROC) analysis and multivariate logistic regression assessed the ability of clinical and biochemical assessments to predict HIE. RESULTS: Sixty neonates met the HIE criteria: 39 were moderate-severe HIE. Univariate analyses identified clinical neonatal markers (Apgar scores and neonatal resuscitation level) to be better HIE predictors than biochemical markers (umbilical artery pH, base excess and lactate values). Multivariable models using two to four predictors had areas under ROC curves up to 0.98, sensitivities up to 93% and specificities up to 99%. For moderate-severe HIE, the most effective predictor was neonatal resuscitation level and arterial lactate (ROC 0.98, sensitivity 85%, specificity 99%). CONCLUSION: The combination of umbilical arterial lactate and neonatal resuscitation level provides a rapid and accurate method of predicting moderate-severe HIE that can identify neonates at birth that may benefit from tertiary care and neuroprotective therapies.

The effect of time, temperature and storage device on umbilical cord blood gas and lactate measurement: a randomized controlled trial.

OBJECTIVE: Umbilical cord blood gas analysis has a significant and growing role in early neonatal assessment. Factors often delay analysis of cord blood allowing values to change. Consequently, this study evaluates the impact of time, temperature and method of storage on umbilical blood gas and lactate analyses. METHODS: Umbilical cord segments from 80 singleton deliveries were randomized to: cords at room temperature (CR), cords stored on ice (CI), syringes at room temperature (SR) or syringes stored on ice (SI). Analysis occurred every 15 minutes for one-hour. Mixed model analysis of variance allowing for repeated measures was utilized. RESULTS: Cord arterial pH deteriorated in CR, CI, and SI within 15 minutes (p ≤ 0.001), with SR stable until 60 minutes (p = 0.002). Arterial pCO(2) remained stable in SR and CI, increased in SI (p = 0.002; 45 minutes) and decreased in CR (p < 0.001; 45 minutes). Arterial base excess deteriorated in CR and SI (p ≤ 0.009; 15 minutes), SR (p < 0.001; 30 minutes), and CI (p < 0.001; 45 minutes). Arterial lactate levels increased within 15 minutes in all groups (p < 0.001). CONCLUSIONS: Cord blood gas values change rapidly after delivery. Smallest changes were seen in SR group. Data suggest that analyses should be conducted as soon as possible after delivery.

Effect of an extended midwifery postnatal support programme on the duration of breast feeding: a randomised controlled trial.

OBJECTIVE: to evaluate the effects of an extended midwifery support (EMS) programme on the proportion of women who breast feed fully to six months. DESIGN: randomised controlled trial. SETTING: large public teaching hospital in Australia. PARTICIPANTS: 849 women who had given birth to a healthy, term, singleton baby and who wished to breast feed. INTERVENTION: participants were allocated at random to EMS, in which they were offered a one-to-one postnatal educational session and weekly home visits with additional telephone contact by a midwife until their baby was six weeks old; or standard postnatal midwifery support (SMS). Participants were stratified for parity and tertiary education. MEASUREMENTS: the main outcome measures were prevalence of full and any breast feeding at six months postpartum. FINDINGS: there was no difference between the groups at six months postpartum for either full breast feeding [EMS 43.3% versus SMS 42.5%, relative risk (RR) 1.02, 95% confidence interval (CI) 0.87-1.19] or any breast feeding (EMS 63.9% versus SMS 67.9%, RR 0.94, 95%CI 0.85-1.04). CONCLUSIONS: the EMS programme did not succeed in improving breast-feeding rates in a setting where there was high initiation of breast feeding. Breast-feeding rates were high but still fell short of national goals. IMPLICATIONS FOR PRACTICE: continuing research of programmes designed to promote breast feeding is required in view of the advantages of breast feeding for all mothers and babies.

Effects of antenatal corticosteroids on urinary markers of the initiation of lactation in pregnant women.

BACKGROUND: Antenatal corticosteroids are given to most women at risk of preterm delivery, although many do not eventually deliver preterm. Profound disruptions of lactation have been shown in ewes after antenatal corticosteroid treatment, but little is known of the effect on lactation in women. This study aimed to investigate the effects of antenatal corticosteroid treatment on mammary secretion during pregnancy in women. METHODS: We conducted a prospective cohort study of women receiving betamethasone for anticipated preterm delivery (n = 87). Women collected 24-hour urine samples on days 1, 2, 3, 5, 7, and 14 after treatment if they remained pregnant. We measured urinary excretion of pregnanediol glucuronide (PdG), a major metabolite of progesterone and lactose, which indicates mammary secretion during pregnancy. Withdrawal of progesterone triggers the onset of mammary secretion. RESULTS: Median (range) gestational age at treatment was 28.8 (23.6-33.6) weeks. A total of 330 24-hour urine samples were collected. Median (range) excretion of PdG was 1.355 (0.139-5.069) mmol/24 hours, and lactose excretion was 0.823 (0.035-6.676) mmol/24 hours. Both PdG and lactose excretion increased with increasing gestational age (P < 0.001). After adjustment for gestational age, there were significant transient increases in lactose excretion (P < 0.001) after betamethasone treatment but no changes in PdG excretion (P = 0.435). CONCLUSIONS: Antenatal betamethasone treatment was associated with a transient premature secretory activation while women were still pregnant.

Effect of preterm birth and antenatal corticosteroid treatment on lactogenesis II in women.

OBJECTIVE: The onset of copious milk secretion after birth is known as lactogenesis II. The objective of this study was to investigate the effect of preterm birth and antenatal corticosteroids on the timing of lactogenesis II after birth. METHODS: Women who had received antenatal betamethasone treatment and were expressing for a preterm infant whose gestational age was <34 weeks (N = 50) were included. On days 1 to 10 postpartum, participants measured the volume of milk expressed in 24-hour periods and collected milk samples. Lactose and citrate levels were analyzed in the milk. RESULTS: The gestational age at delivery was 31 weeks (range: 24.2-33.7). Milk volume was recorded by 46 women on 320 expression days and was positively associated with gestational age. Gestational age modified the effect of interval between betamethasone administration and delivery on milk volume. At gestational age 28 to 34 weeks, women who delivered 0 to 2 days after betamethasone treatment obtained significantly greater volumes than women who delivered 3 to 9 days after treatment. Milk samples (N = 324) were collected by 42 mothers. Mean +/- SD lactose and citrate levels were 156.800 +/- 36.217 and 3.458 +/- 1.442 mM, respectively. There was a significant positive effect of gestational age on milk lactose levels but not citrate levels. Betamethasone treatment did not alter lactose or citrate levels in milk. CONCLUSIONS: Delivery at extremely preterm gestational ages caused a significant delay in the onset of lactogenesis II. The volume of milk was reduced further when antenatal corticosteroids were administered between 28 and 34 weeks' gestation and delivery occurred 3 to 9 days later. In view of the advantages of mothers' own milk, additional support with lactation is recommended for mothers of preterm infants, particularly those who have been treated with corticosteroids before the delivery.

Impact of intrapartum epidural analgesia on breast-feeding duration.

BACKGROUND: Although the labour and delivery outcomes of epidural analgesia have been investigated extensively, the effects on breast-feeding success are not clearly identified. AIM: To investigate the effects of intrapartum epidural analgesia on breast-feeding duration. METHODS: Nulliparous women enrolled in a randomised trial investigating labour and delivery outcomes of intrapartum epidural analgesia were asked about breast-feeding outcomes. Breast-feeding duration was ascertained by a self-report at 2 and 6 months post-partum. Breast-feeding outcomes were analysed as a prospective observational study because of high cross-over rates (43.4%) in the original randomised controlled trial. RESULTS: A total of 992 women were recruited to the trial with 690 (69.6%) receiving epidural analgesia in labour. Breast-feeding was initiated by 95% (n = 946). At 2 and 6 months, 625 (63.5%) and 401 (40.7%), respectively, were still breast-feeding. Intrapartum analgesia (trend P-value = 0.036), mode of delivery (P < 0.001), age (P < 0.001), education (P < 0.001), and smoking in pregnancy (P < 0.001) showed univariate associations with breast-feeding duration. In the subgroup of women with spontaneous onset of labour and vaginal deliveries, after controlling for other obstetric and demographic factors, epidural analgesia but not narcotic analgesia was significantly associated with reduced breast-feeding duration (adjusted hazard ratio 1.44, 95% confidence interval 1.04-1.99). CONCLUSIONS: Nulliparous women have a high use of epidural analgesia in labour. Nulliparous women who choose epidural analgesia are more likely to breast-feed for shorter durations. Further exploration of the factors underlying this association should be undertaken.

Impact of postnatal depression on breastfeeding duration.

BACKGROUND: Postnatal depression can cause adverse effects on both mother and infant, but its impact on breastfeeding duration is poorly understood. The aim of this study was to investigate the relationship between maternal postnatal depression and breastfeeding duration. METHODS: A cohort of 1745 women was recruited on the postnatal wards of two large Australian obstetric hospitals. Self-report questionnaires were completed at recruitment, and at 2, 6, and 12 months postpartum. Breastfeeding status was determined at each follow-up, and the Edinburgh Postnatal Depression Scale was used to screen for symptoms of depression. Diagnostic psychological interviews were conducted on a subsample of women at each interval. RESULTS: Breastfeeding was initiated by 96 percent of the participants; at 2 months 79 percent were still breastfeeding, 57 percent at 6 months, and 22 percent at 12 months. Of the 18 percent of participants diagnosed with postnatal depression, the onset occurred before 2 months in 63 percent of cases. Median duration of breastfeeding was 26 weeks for women with early-onset depression, 28 weeks for women with late-onset depression, and 39 weeks for women without depression. After adjustment for confounding factors, early cessation of breastfeeding was found to be significantly associated with postnatal depression (adjusted hazard ratio 1.25, 95% CI 1.03-1.52). Onset of postnatal depression occurred before cessation of breastfeeding in most cases. CONCLUSIONS: Postnatal depression has a significant negative impact on breastfeeding duration. Assistance with breastfeeding issues should be included in the management of postnatal depression.