Effects of maternity on auditory event-related potentials to human sound.

Auditory event-related brain potentials (ERPs) were recorded in response to an emotional (a baby's cry) and a neutral (a word) stimulus in a group of mothers 2-5 days after childbirth (n = 20) and in control women (n = 18) who were not in the state of early motherhood. For each mother, her own infant's cry was recorded and used as the cry stimulus, whereas a strange baby's cry was used for control women. The word stimulus was identical for both groups. Stimuli were presented in intermittent trains in order to study the arousal responses to the first stimuli of the trains, and refractoriness of ERPs during stimulus repetition. The N100 responses were significantly larger in amplitude in mothers than in control women, not only to the emotional cry stimuli but also to the neutral word stimuli. The finding suggests a general increase in alertness and arousal in mothers, which may be necessary in enabling the mother to be continuously alert to her infant's needs. This allows good care of the infant and may be essential in building an emotional tie between the mother and her child.

Dynamic behavior of the auditory N100 elicited by a baby's cry.

We compared auditory N100 responses in female adults to two non-attended human sound stimuli. An infant's cry represented an unfamiliar, emotionally colored sound and the Finnish word "hei" (meaning "hi") a familiar and emotionally neutral sound. Both sounds elicited clear N100 responses over auditory areas in both hemispheres. However, the dynamic behavior of the N100 response following the first few repetitions of the sounds was significantly different. We observed faster habituation and longer response latencies, particularly over the ipsilateral hemisphere, during the first and second repetitions of the cry stimulus. This pattern may reflect an altered arousal level and slower, bilateral processing during the unfamiliar emotionally loaded cry as compared to the emotionally neutral word "hei" .

The effect of nursing on the brain activity of the newborn.

OBJECTIVE: To determine whether nursing influences brain activity in the newborn and whether there are differences in this respect between breast- or bottle-feeding and pacifier sucking. STUDY DESIGN: Fifty unselected volunteer mothers and their healthy full-term infants, under care in the maternity ward after delivery, served as subjects. Thirty mother-infant pairs were studied in relation to breast-feeding and 20 to bottle-feeding and pacifier sucking. Breast-fed infants were studied between the 1st and 7th day after delivery (mean +/- 2.7 days) and the infants in the bottle-fed group between the 1st and 8th day after delivery (mean +/- 3.3 days). METHODS: Qualitative and quantitative electroencephalogram (EEG), electrooculogram, submental electromyogram, and electrocardiogram were recorded before, during and after breast- and bottle-feeding and pacifier sucking. RESULTS: The amplitude of the EEG increased significantly during breast-feeding in the posterior cortical areas in both hemispheres with a slight predominance on the right. Bottle-feeding caused a similar, but somewhat less marked change. When the breast- and bottle-fed infants were compared, a significant difference was found in only one parameter of the 84 studied. Pacifier sucking had no significant effects on EEG activity. CONCLUSION: Nursing effects a change in the brain activity of the newborn. The cortical response to nursing is most probably a result of activation of the neurohumoral mechanisms related to hunger and satisfaction, including the hypothalamic, limbic, and other brain stem structures, which also regulate the sleep-wake cycle and modulate the level of cortical activity with respect to attention and vigilance.

The use of hCG and other pregnancy proteins in the diagnosis of ectopic pregnancy.

Early diagnosis of ectopic pregnancy has been greatly improved by three diagnostic advances: the development of rapid and highly sensitive pregnancy tests, advances in ultrasound examination, and laparoscopy. The estimation of hCG is clinically superior to the measurement of any other pregnancy protein or biochemical parameter. If an hCG test has a sensitivity of 25 IU/1, then 90-100% of ectopic pregnancies will give a positive result. But, the hCG test cannot distinguish between intrauterine and ectopic pregnancy, and here ultrasonic examination and laparoscopy are routine diagnostic measures to identify the site of trophoblastic activity. If highly sensitive hCG tests are used routinely, they may detect small amounts of hCG so early in ectopic pregnancy that the tubal swelling is missed, or hCG may be reminiscent from trophoblastic activity of a previous regressing intrauterine or ectopic pregnancy. The lesson we learn from such cases is that a patient with an elevated hCG level in whom an intrauterine pregnancy has been excluded should be carefully followed-up as long as hCG remains elevated because of the possibility of an early ectopic pregnancy.

The monitoring of labor by telemetry.

Telemetry and conventional cardiotocography were compared by monitoring the labor of 60 patients with an uneventful pregnancy and delivery in the 38th-42nd week of pregnancy. 31 patients were monitored by telemetry and 29 by cardiotocography. The patients were matched for age (+/- 5 years), duration of pregnancy (+/- 7 days) and parity (I or II). The husband attended labor and delivery in 42% of the cases in the telemetry group and in 59% of the cases in the control group. Induction of labor by amniotomy was performed in 32% of the cases in the telemetry group and in 24% of the cases in the cardiotocography group. The patients monitored subjective pain every half hour during the opening phase. The telemetric patients were encouraged to sit or walk during the first stage. No maternal or fetal complications occurred. All infants were born in good condition with APGAR scores greater than or equal to 7 recorded at one and five minutes. There were 4 operative deliveries in the telemetry group and 5 in the control group. Indications for these were maternal or uterine exhaustion with the exception of two control patients where fetal asphyxia was suspected. The duration of the first stage of labor did not differ significantly between the telemetry and the cardiotocography groups. The telemetric patients received less analgesics than the controls but this difference was not significant. In spite of less analgesia in the telemetry group, the secondparas of the telemetry group experienced significantly less (p less than 0.01) labor pain than the controls. In addition, the secondparas of the telemetry group considered the present labor less painful than the previous one significantly more often than the controls. Among the primiparous patients there was no difference in the amount of pain experienced by the patients.

Maternal and foetal drug levels after epicutaneous application of a local anaesthetic formulation containing ketocaine for possible use as pain relief in labour.

A local anaesthetic formulation (A 2358) containing ketocaine, a local anaesthetic drug, was applied epicutaneously to the low back. Two compresses soaked with A 2358 were applied for 1 hour in 26 normal labours for relieving referred pain from the low back. The maternal blood ketocaine levels remained low, compared to higher systemic levels reported in other studies. Maternal heart rate and blood pressure were stable during the application time. The mean umbilical vein/maternal vein and umbilical artery/maternal vein concentration ratios were 0.20 +/- 0.10 and 0.21 +/- 0.09. In addition, the foetal heart rate findings and the conditions of the neonates were satisfactory, thus suggesting the foetal safety of this analgesic method.