Muscular Fitness Improves during the First Year of Academy Studies among Fighter Pilot Cadets

Background: An adequate level of muscular fitness is related to occupational performance in military personnel, including pilots flying high performance aircraft. The aim of this study was to describe the baseline level and the change in muscular fitness between the first and the second years of the Air Force Academy among fighter pilot cadets. Methods: The muscular strength and endurance test results of 182 male fighter pilot cadets were analyzed during their first year in the Air Force Academy and one year after. Maximal isometric strength tests included trunk flexion, trunk extension and bilateral leg extension tests, whereas muscle endurance was measured with modified a sit-up test and seated alternative dumbbell press. Results: The maximal isometric bilateral strength of the leg extensor muscles increased from 220 ± 42 to 232 ± 42 kg. The maximal isometric trunk extension strength increased from 117 ± 21 to 120 ± 19 kg and trunk flexion from 82 ± 16 to 86 ± 17 kg. Muscle endurance increased from 68 ± 13 to 75 ± 15 repetitions/min in seated dumbbell press and from 47 ± 12 to 51 ± 13 repetitions/min in sit-up test. Conclusions: Both maximal strength and muscular endurance improved among fighter pilot cadets, which indicates that occupational performance is well maintained or improved from the perspective of physical fitness during the early phase of academy studies. Education in the Air Force Academy, including physical education, seems beneficial in improving muscular fitness among military pilots.

Microbial characteristics in homes of asthmatic and non-asthmatic adults in the ECRHS cohort

Microbial exposures in homes of asthmatic adults have been rarely investigated; specificities and implications for respiratory health are not well understood. The objectives of this study were to investigate associations of microbial levels with asthma status, asthma symptoms, bronchial hyperresponsiveness (BHR), and atopy. Mattress dust samples of 199 asthmatics and 198 control subjects from 7 European countries participating in the European Community Respiratory Health Survey II study were analyzed for fungal and bacterial cell wall components and individual taxa. We observed trends for protective associations of higher levels of mostly bacterial markers. Increased levels of muramic acid, a cell wall component predominant in Gram-positive bacteria, tended to be inversely associated with asthma (OR's for different quartiles: II 0.71 [0.39-1.30], III 0.44 [0.23-0.82], and IV 0.60 [0.31-1.18] P for trend .07) and with asthma score (P for trend .06) and with atopy (P for trend .02). These associations were more pronounced in northern Europe. This study among adults across Europe supports a potential protective effect of Gram-positive bacteria in mattress dust and points out that this may be more pronounced in areas where microbial exposure levels are generally lower.

MRI findings and physical performance as predictors of flight-induced musculoskeletal pain incidence among fighter pilots

Study aim: The aim of this study was to evaluate the possible association of pre-career magnetic resonance imaging (MRI) find­ings and physical performance level with possible musculoskeletal disorders during jet flight training. Material and methods: The study group consisted of 73 fighter pilots who had undergone pre-career cervical and lumbar spine MRI. Physical performance of a subgroup of the pilots (n = 67) was measured initially at the same time and followed up to the fast jet training phase (ranging from 3.8 to 7.0 years). Musculoskeletal pain history during pilot training was taken from the medical charts. MRI findings and physical performance were associated with perceived clinical complaints during the follow-up. Results: 82% of the cervical and 92% of the lumbar spines showed abnormalities at at least one disk level. MRI did not reveal significant cervical degeneration. Thirteen disk bulges in the lumbar spine were discovered, while 5 pilots had listhesis and/or osteophyte formation on the spine (lumbar vertebra 4/sacroiliac joint level, L4-SI). 41% of the studied pilots suffered spinal symptoms during the follow-up, but only 16% and 17% of the cervical and lumbar MRI findings, respectively, were associated with subsequent symptoms. Endurance and strength levels were not, but lower body motor skills were, strongly (relative risk, RR 0.46) associated with a decreased number of flight-induced medical appointments in the early flight career. Conclusions: Minor MRI findings have no predictable value in the very early flight career. Nevertheless, versatile, skills/power-oriented exercises before the flight career seem to be occupationally beneficial in reducing musculoskeletal disorders.

Relationships Between Physical Fitness, Demands of Flight Duty, and Musculoskeletal Symptoms Among Military Pilots

Although the mechanisms of G-induced stresses on the spinal structure of military pilots are well understood, less is known about relationships between the intensity of physical activity, fitness, occupational musculoskeletal symptoms, and the degree of resulting disabilities. During an aeromedical examination, Finnish military pilots answered a questionnaire on their flying experience, the occurrence of flight duty-related pain, the degree of resulting disabilities, and the intensity of physical activity they conducted. 195 males were selected for further analysis. They were divided into three groups, designated high G, low G, and HQ, according to their current flight duty profile. 93% of pilots who had passed fighter lead-in training reported flight duty-induced musculoskeletal disorders. The high-G group exhibited the highest aerobic capacity (p < 0.001) and muscular fitness scores (p < 0.001). The fittest individuals suffered markedly fewer disabilities than their less fit counterparts (p = 0.005). Flight hour accumulation among the subjects in the high-G group was associated (p = 0.010) with the occurrence of flight duty-induced disabilities. The fittest pilots flew aircraft that induce the heaviest accelerations. They also reported more musculoskeletal pain than the other pilots. Yet they seemed to experience fewer disabilities, which highlights the importance of physical training in the maintenance of operational readiness.

Quantity and diversity of environmental microbial exposure and development of asthma: a birth cohort study

Background

Early-life exposure to environmental microbial agents may be associated with the development of allergies. The aim of the study was to identify better ways to characterize microbial exposure as a predictor of respiratory symptoms and allergies.

Methods

A birth cohort of 410 children was followed up until 6 years of age. Bacterial endotoxin, 3-hydroxy fatty acids, N-acetyl-muramic acid, fungal extracellular polysaccharides (EPS) from Penicillium and Aspergillus spp., β-D-glucan, ergosterol, and bacterial or fungal quantitative polymerase chain reactions (qPCRs) were analyzed from dust samples collected at 2 months of age. Asthma, wheezing, cough, and atopic dermatitis were assessed using repeated questionnaires. Specific IgEs were determined at the age of 1 and 6 years.

Results

Only few associations were found between single microbial markers and the studied outcomes. In contrast, a score for the total quantity of microbial exposure, that is, sum of indicators for fungi (ergosterol), Gram-positive (muramic acid) bacteria, and Gram-negative (endotoxin) bacteria, was significantly (inverted-U shape) associated with asthma incidence (P < 0.001): the highest risk was found at medium levels (adjusted odds ratio (aOR) 2.24, 95% confidence interval (95% CI) 0.87–5.75 for 3rd quintile) and the lowest risk at the highest level (aOR 0.34, 95% CI 0.09–1.36 for 5th quintile). The microbial diversity score, that is, sum of detected qPCRs, was inversely associated with risk of wheezing and was significantly (inverted-U shape) associated with sensitization to inhalant allergens.

Conclusion

Score for quantity of microbial exposure predicted asthma better than single microbial markers independently of microbial diversity and amount of dust. Better indicators of total quantity and diversity of microbial exposure are needed in studies on the development of asthma.

Effect of moisture-damage intervention on the immunotoxic potential and microbial content of airborne particles and on occupants' upper airway inflammatory responses

This intervention study evaluated the effect of moisture-damage repairs on the exposure and on the upper airway inflammatory responses of the occupants. The airborne microbial exposure was followed by quantitative PCR analyses of 13 microbial species in repeated long-term indoor air samples before (N = 26) and after (N = 28) repairs of the school building. Airborne particulate matter was collected similarly from the same premises (before N = 25, after N = 34) for determination of nitric oxide (NO), tumor necrosis factor α (TNFα), and interleukin-6 (IL-6), measured in the cell culture medium of mouse macrophages. NO, TNFα, IL-6, and IL-4 were also analyzed in the nasal lavage (NAL) samples of the occupants (N = 13) to characterize their upper airway inflammatory responses during the exposure and after its cessation. After the repairs, concentrations of the measured airborne microbes decreased, the difference being significant for six of 13 species. After renovation, airborne particulate matter also caused significantly lower production of IL-6 and TNF-α in mouse macrophages than the material collected before the renovation. The concentration of IL-4 in the NAL samples was significantly lower after the renovation. These results show that the inflammatory potential of the airborne material decreases after intensive repair of the moisture damage.

Evaluation of quantitative PCR and culture methods for detection of house dust fungi and streptomycetes in relation to moisture damage of the house

AIMS

Microbial concentrations in vacuumed house dust samples (n = 71) were analysed by culture and quantitative polymerase chain reaction (qPCR) methods and their association with extent of moisture damage in the house was studied.

METHODS AND RESULTS

Microbial concentrations measured by qPCR correlated with concentrations obtained by culture method, but were orders of magnitude higher. qPCR also had better sensitivity. Concentrations of several microbes in house dust, determined with qPCR, were associated with the extent of moisture damage in the house. This association was strongest for Penicillium brevicompactum, one of the fungi detected in highest concentrations by qPCR. Furthermore, house dust concentrations of Wallemia sebi, Trichoderma viride, Cladosporium sphaerospermum, Eurotium amstelodami and the combined assay group for Penicillium spp., Aspergillus spp. and Paecilomyces variotii were significantly associated with the extent of the moisture damage.

CONCLUSION

These species or assay groups could probably be used as indicators of moisture damage in the house.

SIGNIFICANCE AND IMPACT OF THE STUDY

This finding indicates the benefits of the qPCR method, which is sensitive enough to reveal the differences in microbial concentrations of house dust between moisture-damaged and undamaged houses.

Neck and back muscle loading in pilots flying high G(z) sorties with and without lumbar support

INTRODUCTION

Fighter pilots frequently encounter neck and back pain and injuries due to high G(z) loading. A lumbar support could diminish muscle strain in the lower back under G(z) loading and might also have a positive effect on cervical muscle strain, due to a more ergonomic sitting posture. The aim of this study was to determine the effects of individually adjusted lumbar supports on fighter pilots' neck and back muscle loadings.

METHODS

There were 11 Finnish Air Force pilots who acted as test subjects. They flew two basic air combat maneuvering sorties with and without the LS. The EMG activity of the sternocleidomastoid (SCM), cervical (CES), thoracic (TES), and lumbar erector spinae muscles (LES) were measured during these sorties, and the number and duration of EMG gaps was analyzed. Subjective experiences about the lumbar support were evaluated using a questionnaire.

RESULTS

In all measured muscles, mean percent maximal voluntary contraction (%MVC) was lower when the LS was used, yet these changes were not statistically significant. Individual differences in %MVC between flights diminished in the CES (9%), TES (7%), and LES (8%) with LS in use. There was also a tendency toward increased number of gaps in EMG activity when flying with the LS. According to questionnaire responses, the LS seems to relieve in-flight symptoms and reduce the fatigue in the lower back muscles. Not all subjects benefited from the LS, however.

CONCLUSION

There seems to be a tendency toward a lower muscle strain with the LS, but there are considerable individual differences.

Neck muscle strain when wearing helmet and NVG during acceleration on a trampoline

INTRODUCTION

The helmet-mounted equipment worn by military pilots increases the weight of the helmet system and shifts its center of gravity, increasing the loads on neck structures, especially during acceleration. The aim of this study was to determine neck muscle strain with different head-loads during trampoline-induced G loads (0 to +4 G).

METHODS

Under three conditions [no helmet, helmet, helmet with night vision goggles (NVG)], 14 subjects performed trampoline exercises including basic, hand-and-knee, and back bouncing. EMG activity was measured for the sternocleidomastoid (SCM), cervical erector spinae (CES), trapezoid (TRA), and thoracic erector spinae (TES) muscles. Muscle strain was determined as a percentage of maximal voluntary contraction (%MVC).

RESULTS

For the three exercises combined, the following significant changes were found: compared to control, the helmet increased muscle strain by 18%, 28%, and 18% in the SCM, CES, and TRA, respectively; NVG produced a further increase of 11% in the SCM and 6% in the CES. During back bouncing, the helmet increased muscle strain by 14% in the SCM and 19% in the CES, and NVG further increased this strain by 14% in the SCM. Hand-and-knee bouncing loaded extensors: the helmet caused increases of 46% in the CES and 29% in the TES, while NVG produced a further 13% increase in CES activation.

CONCLUSION

Helmet weight alone had a large effect on muscular workload. The additional frontal weight of the NVG caused a further increase in the activity of cervical muscles that were already subjected to high strain.

Ambient temperature and neck EMG with +Gz loading on a trampoline

INTRODUCTION

Fighter pilots who are frequently exposed to severe cold ambient temperatures experience neck pain disabilities and occupational disorders more often than those who are not so exposed. We hypothesized that a cold-induced increase in muscle strain might lead to in-flight neck injuries. The aims of this study were to measure the level of cooling before takeoff and to determine muscle strain under Gz loading (0 to +4 Gz) at different temperatures.

METHODS

Test subjects' (n = 14) skin temperature (T(skin)) over the trapezoids was measured before the walk to the aircraft and again in the cockpit (air temperature -14 degrees C). The subjects then performed trampoline exercises in two different ambient temperatures (-2 degrees C and +21 degrees C) after a 30-min period at the respective temperatures. EMG activity of the sternocleidomastoid (SCM), cervical erector spinae (CES), trapezoid (TRA), thoracic erector spinae (TES) muscles, and Tskin of the SCM and TRA were measured.

RESULTS

Tskin over the trapezoids decreased from 30.1 +/- 1.7 degrees C to 27.8 +/- 2.6 degrees C (p < 0.001) before takeoff. The change of muscle strain in cold was +11.0% in SCM, +14.9% in CES, +3.7% in TRA, and -1.7% in TES. Change was statistically significant in the cervical, uncovered area (SCM, CES). The linear regression model indicated a 2.6% increase in muscle strain per every decreased degree centigrade in skin temperature over the SCM.

CONCLUSION

Superficial cooling over the neck muscles was significant prior to takeoff. Muscle loading in the cold caused higher EMG activity. A major increase in muscle strain was seen in the cervical muscles. These findings suggest a cold-induced increase in muscle strain during in-flight Gz loading.

Trampoline exercise vs. strength training to reduce neck strain in fighter pilots

INTRODUCTION

Fighter pilots' muscular strength and endurance are subjected to very high demands. Pilots' fatigued muscles are at higher risk for injuries. The purpose of this study was to compare the effects of two different training methods in reducing muscular loading during in-flight and cervical loading testing (CLT).

METHODS

There were 16 volunteer Finnish Air Force cadets who were divided into 2 groups: a strength training group (STG) and a trampoline training group (TTG). During the 6-wk training period, the STG performed dynamic flexion and extension and isometric rotation exercises, and the TTG performed trampoline bouncing exercises. During in-flight and CLT, muscle strain from the sternocleidomastoid, cervical erector spinae, trapezius, and thoracic erector spinae muscles was recorded with EMG.

RESULTS

In-flight muscle strain in the STG after the training period decreased in the sternocleidomastoid 50%, cervical erector spinae 3%, trapezius 4%, and thoracic erector spinae 8%. In the TTG, the decrease was 41%, 30%, 20%, and 6%, respectively. In CLT, the results were similar. After a 3-mo follow-up period with intensive high +Gz flying, EMG during CLT was still lower than in baseline measurements.

CONCLUSION

Both training methods were found to be effective in reducing muscle strain during in-flight and CLT, especially in the cervical muscles. There was no statistically significant difference between the training groups. Introduced exercises expand muscles' capacities in different ways and the authors recommend both strength and trampoline training programs to be included in fighter pilots' physical education programs.

Detection of streptomycetes in house dust--comparison of culture and PCR methods

Streptomycetes are gram-positive, spore producing, filamentous bacteria common in soil, but also present in indoor environments. They are potent producers of secondary metabolites and inducers of inflammatory responses in vitro. Polymerase chain reaction (PCR)- and culture-based detection methods for streptomycetes in house dust samples were compared. A total of 47 dust samples were investigated, and the presence of streptomycetes was determined by cultivation on tryptone-yeast-extract-glucose agar and PCR. The 16S rRNA gene of actinomycete isolates from house dust was partially sequenced to investigate if they belong to the genus Streptomyces. Both PCR and culture showed more frequent occurrence of streptomycetes in moisture-damaged homes, although the results did not correlate well. The occurrence of streptomycetes in house dust was associated with moisture damage of the home. The amount of Streptomyces-specific PCR amplification product was significantly higher in dust from moisture-damaged homes than in homes with no moisture damage (P < 0.05, Mann-Whitney U test). A correlation between streptomycetes and moisture damage, although not statistically significant, was also observed when using binary data, e.g. presence or absence of streptomycetes or moisture damage (P = 0.054 for PCR, and P = 0.127 for culture, Fisher's exact test). Altogether, the presence of streptomycetes in house dust seems to indicate the presence of moisture damage in the building.

The effect of lumbar support on the effectiveness of anti-G straining manuevers

INTRODUCTION

The ability of fighter pilots to perform efficient anti-G straining maneuvers (AGSM) is vital for their G-tolerance. The aim of this study was to evaluate if the use of a lumbar support that optimizes the posture of the spine enhances the effectiveness of AGSM.

METHODS

Eleven fighter pilots performed four AGSM training sessions with 4-5 repetitions in each session, each lasting approximately 10 s. The sessions were done without lumbar support or using supports that were 7, 14, or 26 mm thick. During the sessions, the electromyogram (EMG) data were recorded from eight muscles (rectus and biceps femoris, gluteus maximus, erector spinae, rectus abdominis, obliquus externus, latissimus dorsi, and pectoralis major).

RESULTS

In a single best AGSM, average EMG (aEMG) increased 12%, 10%, and 14% and power spectrum area (PSA) increased 20%, 26%, and 44% while using 7-, 14-, and 26-mm supports, respectively, in relation to the condition without support. According to aEMG and PSA, effectiveness increased in 11 and 10 subjects, respectively, with the average increase being 12% (aEMG) and 25% (PSA). During the whole session (repeated AGSM), effectiveness was best with support in 7 subjects and without support in 4 subjects. In the total population, the average increase in the effectiveness during repeated AGSM was 6% and 11% with aEMG and PSA, respectively.

DISCUSSION

The use of lumbar support tended to increase the effectiveness of muscular work, especially during single AGSM, but also during repeated AGSM.

Diversity of streptomycetes in water-damaged building materials based on 16S rDNA sequences

AIMS

The diversity of streptomycetes in two different types of water-damaged building materials was investigated.

METHODS AND RESULTS

Direct PCR amplification of 16S rDNA from DNA isolated from building materials, cloning of the fragments and sequence analysis were used. In the phylogenetic analysis of the variable gamma region of the PCR amplification products, the sequences affiliated with five groups.

CONCLUSIONS

Several different sequences were found in both materials, suggesting the presence of several species. Also, previously unknown sequences were detected, although all the sequences clustered together with sequences of known species.

SIGNIFICANCE AND IMPACT OF THE STUDY

Streptomycetes are known as indicators for moisture and mould damage in buildings and potential health risk, but their diversity in indoor environments is still unknown.

PCR primers targeting the 16S rRNA gene for the specific detection of streptomycetes

Streptomycetes are filamentous actinobacteria commonly found in soil and biotechnically important, but they also have adverse effects on human health. In this work, two primer pairs, StrepB/StrepE and StrepB/StrepF combined with Bst YI restriction endonuclease digestion, targeting the 16S rRNA gene of streptomycetes were designed. The specificity of the primers was determined by polymerase chain reaction (PCR) amplification from Streptomyces strains and near relatives. All streptomycetes tested positive and non-streptomycetes were not amplified except three strains that, however, gave Bst YI restriction endonuclease digestion results distinct from streptomycetes. Moreover, both primer pairs gave an amplification product of the expected size only when Streptomyces VTT E-99-1334 DNA was present in the template DNA mixture isolated from six bacterial and three fungal strains. The primers were further successfully used to amplify from DNA isolated from two soil and two building material samples. The 40 sequenced amplification products obtained with the primer pair StrepB/StrepE showed greater than 96.1% similarity to streptomycete 16S rRNA sequences. Seventy PCR amplification products obtained with the primers StrepB/StrepF were analysed by sequencing and restriction analysis. All 54 PCR products having >95.7% similarity to streptomycete sequences were cleaved with Bst YI. No false-positive results were achieved. Both primer sets proved to be specific for streptomycetes, and applicable for the detection of streptomycetes in environmental samples.

Androgen receptor function during undernutrition

Hypothalamo-pituitary inhibition of reproductive function during undernutrition is well known, however, the physiological mechanisms leading to suppression of gonadotrophin secretion are not clear. A variety of studies have indicated that testicular negative feedback on LH secretion is enhanced during food restriction. To evaluate directly the suppression by endogenous androgens on hypothalamic GnRH pulse generator activity during food restriction and examine the mechanism underlying the increased testicular steroidal feedback, we examined (1) circulating bioactive LH (bLH) levels in response to selective cerebral androgen blockade by intraventricular administration of an androgen receptor antagonist (hydroxyflutamide, SCH 16423) and (2) the binding capacity and affinity of androgen receptors in medio-basal hypothalamus, pituitary and prostate during undernutrition of intact mature male rats. Hydroxyflutamide (20 micrograms in 10 microliters vehicle), but not vehicle alone, markedly increased bLH levels in both food restricted and ad-lib fed rats. However, the faster (geometric mean 11.4 vs 27.7 min) and greater (47.2 vs 21.9 ng/ml) increase in bLH level in food restricted compared with ad-lib fed controls demonstrates an enhanced sensitivity to blockade of androgenic negative feedback during undernutrition. Food restriction increased androgen receptor binding capacity in pituitary (3.36 vs 0.77 fmol/mg protein) but not in medio-basal hypothalamus or prostate while binding affinity was unchanged by undernutrition in all 3 tissues. These studies reveal that undernutrition both enhances tonic, androgen receptor-mediated feedback suppression of GnRH secretion and increases in pituitary (but not hypothalamic) androgen receptor numbers to cause inhibition of LH secretion.

LH pulsatility, biopotency, and clearance during undernutrition in orchidectomized mature rats

The effect of food restriction on circulating luteinizing hormone (LH) levels in orchidectomized rats is controversial. The present study demonstrates that decreasing food intake by 50% for 3-10 days in orchidectomized rats increases LH pulse amplitude, length, area under pulse curve, and mean levels but decreases LH pulse frequency compared with ad-lib fed, orchidectomized controls. The effects on pulsatile LH secretion of food reduction by 50% with or without dilution by cellulose to maintain food volume in orchidectomized rats were also examined. Food volume influences pulsatile LH secretion independent of macronutrient effect after 3 days of food restriction, but subsequently macronutrient deprivation predominates. The exaggerated increase in LH levels in orchidectomized rats subject to food restriction for 7 days was not due to immunochemical or chromatographic heterogeneity or alteration in biopotency of circulating LH molecules. Intravenously injected 125I-labeled rat LH analyzed by noncompartmental modeling revealed that neither LH clearance nor mean residence time was reduced by food restriction. We conclude that during food restriction in orchidectomized rats, increases in LH pulse amplitude exceed and precede the decreases in LH pulse frequency, although the early changes in pulse amplitude are predominantly due to reduced food volume rather than macronutrient deprivation.

Bilateral tubal pregnancy: a case report and review of the literature

We describe a patient whose secondary infertility was treated with clomifen. She developed a bilateral tubal pregnancy which was confirmed histologically. A short review of the pertinent literature is also presented.

Heterologous gene expression of the glyphosate resistance marker and its application in yeast transformation

The E. coli aroA gene was inserted between yeast promoter and terminator sequences in different shuttle expression plasmids and found to confer enhanced EPSP synthase activity as well as resistance to glyphosate toxicity. Subsequently, a transformation system using these newly constructed vectors in yeast was characterized. The efficiency of the glyphosate resistance marker for transformation and selection with plasmid pHR6/20-1 in S. cerevisiae laboratory strain SHY2 was found to be relatively high when compared with selection for LEU2 prototrophy. The fate of the recombinant plasmid pHR6/20-1 in the transformants, the preservation of the aroA E. coli DNA fragment in yeast, mitotic stability, EPSP synthase activity, and growth on glyphosate-containing medium have been investigated. As this plasmid also allows direct selection for glyphosate resistant transformants on rich media, the glyphosate resistance marker was used for transforming both S. cerevisiae laboratory strain SHY2 and brewer's yeast strains S. cerevisiae var. "uvarum" BHS5 and BHS2. In all cases, the vector pHR6/20-1 was maintained as an autonomously replicating plasmid. The resistance marker is, therefore, suitable for transforming genetically unlabelled S. cerevisiae laboratory, wild, and industrial yeast strains.

Breast stimulation test in fetal surveillance

The usefulness of breast stimulation to elicit uterine contractions as a contraction stress test in fetal surveillance in high-risk pregnancies was investigated. The test was successful in fulfilling the criteria of contraction stress testing in 48 out of 76 mothers (62%). Success rates were not affected by the duration of pregnancy after 36 weeks. Nor did parity have any significant effect. The results of the breast stimulation test (BST) correlated well with the preceding non-stress test. Only one positive BST was detected in this population. In this case the late decelerations were present even during labor the next day. BST seems to be a practicable tool, in preference to the oxytocin challenge test, for fetal surveillance.