Personality traits and pre-treatment beliefs and cognitions predicting patient adherence to continuous positive airway pressure: A systematic review.

Adherence to Continuous Positive Airway Pressure (CPAP) for obstructive sleep apnoea (OSA) can be improved by behavioural interventions which modify patients' beliefs and cognitions about OSA, CPAP, and themselves. We have conducted the first systematic review of the literature on beliefs and cognitions held before starting treatment, and personality (which influences the former) that predict the decision to purchase or start CPAP, or CPAP adherence one month or more after CPAP initiation. A systematic search and screen of articles identified 21 eligible publications from an initial 1317. Quality assessment performed using an adapted Newcastle-Ottawa Scale demonstrated that 13 (62%) studies were poor quality and only seven (33%) were high quality. Eighteen factors, such as self-efficacy (confidence) in using CPAP and value placed on health predicted CPAP adherence; however, for only six (33%), utility as an intervention target is known, from calculation of individual predictive power. Studies did not use new behavioural frameworks effective at explaining adherence behaviours, nor did they interview patients to collect in-depth data on barriers and facilitators of CPAP use. Future studies cannot have these limitations if high quality evidence is to be generated for intervention development, which is currently sparse as highlighted by this review.

Electronic Cigarette Advertising Impacts Adversely on Smoking Behaviour Within a London Student Cohort: A Cross-Sectional Structured Survey.

INTRODUCTION: In contrast to tobacco smoking, electronic cigarette ("vaping") advertisement had been approved in the United Kingdom (UK) in January 2013. Currently, there are an estimated 3.2 million UK e-cigarette users. The impact of e-cigarette advertisement on tobacco use has not been studied in detail. We hypothesised that e-cigarette advertisement impacts on conventional smoking behaviour. METHODS: A cross-sectional structured survey assessed the impact of e-cigarette advertising on the perceived social acceptability of cigarette and e-cigarette smoking and on using either cigarettes or e-cigarettes (on a scale of 1 to 5/'not at all' to 'a lot'). The survey was administered between January to March 2015 to London university students, before and after viewing 5 UK adverts including a TV commercial. RESULTS: Data were collected from 106 participants (22 ± 2 years, 66% male), comprising cigarette smokers (32%), non-smokers (54%) and ex-smokers (14%). This included vapers (16%), non-vapers (77%) and ex-vapers (7%). After viewing the adverts, smokers (2.6 ± 1.0 vs. 3.8 ± 1.1, p = 0.001) and non-smokers (3.2 ± 0.7 vs. 3.7 ± 0.8, p = 0.007) felt smoking was more socially acceptable, compared to before viewing them. Participants were more likely to try both e-cigarettes (1.90 ± 1.03 to 3.09 ± 1.11, p < 0.001) and conventional cigarettes (1.73 ± 0.83 to 2.27 ± 1.13, p < 0.001) after viewing the adverts compared to before. Vapers were less likely to smoke both an e-cigarette, and a conventional cigarette after viewing the adverts. CONCLUSION: E-cigarette advertising encourages both e-cigarette and conventional cigarette use in young smokers and non-smokers. The adverts increase the social acceptability of smoking without regarding the importance of public health campaigns that champion smoking cessation.

A cohort study to identify simple clinical tests for chronic respiratory failure in obese patients with sleep-disordered breathing.

BACKGROUND: Chronic respiratory failure complicating sleep-disordered breathing in obese patients has important adverse clinical implications in terms of morbidity, mortality and healthcare utilisation. Screening strategies are essential to identify obese patients with chronic respiratory failure. METHOD: Prospective data were collected from patients with obesity-related sleep-disordered breathing admitted for respiratory assessment at a UK national sleep and ventilation centre. Hypercapnia was defined as an arterial partial pressure of carbon dioxide of >6kPa. RESULTS: 245 obese patients (56±13 years) with a body mass index of 48±12 kg/m(2), forced vital capacity (FVC) of 2.1±1.1 L, daytime oximetry (SpO2) of 91±6% and abnormal overnight oximetry were included in the analysis. Receiver operator curve analysis for the whole group showed that an FVC ≤3 L had a sensitivity of 90% and a specificity of 41% in predicting hypercapnia, and an SpO2 ≤95% had a sensitivity of 83% and a specificity of 63% in predicting hypercapnia. Gender differences were observed and receiver operator curve analysis demonstrated 'cut-offs' for (1) SpO2 of ≤95% for men and ≤93% for women and (2) FVC of ≤3.5 L for men and ≤2.3 L for women, in predicting hypercapnia. CONCLUSIONS: The measurement of FVC and clinic SpO2 in obese patients with abnormal overnight limited respiratory studies predicted hypercapnia. This may have clinical utility in stratifying patients attending sleep clinics.

A UK survey of rehabilitation following critical illness: implementation of NICE Clinical Guidance 83 (CG83) following hospital discharge.

OBJECTIVE: To determine the implementation of National Institute for Health and Care Excellence guidance (NICE CG83) for posthospital discharge critical illness follow-up and rehabilitation programmes. DESIGN: Closed-question postal survey. SETTING: Adult intensive care units (ICUs) across the UK, identified from national databases of organisations. Specialist-only and private ICUs were not included. PARTICIPANTS: Senior respiratory critical care physiotherapy clinicians. RESULTS: A representative sample of 182 surveys was returned from the 240 distributed (75.8% (95% CI 70.4 to 81.2)). Only 48 organisations (27.3% (95% CI 20.7 to 33.9)) offered a follow-up service 2-3 months following hospital discharge, the majority (n=39, 84.8%) in clinic format. 12 organisations reported posthospital discharge rehabilitation programmes (6.8% (95% CI 3.1 to 10.5)), albeit only 10 of these operated on a regular basis. Lack of funding was reported as the most frequent (n=149/164, 90%) and main barrier (n=99/156, 63.5%) to providing services. Insufficient resources (n=71/164, 43.3%) and lack of priority by the clinical management team (n=66/164, 40.2%) were also highly cited barriers to service delivery. CONCLUSIONS: NICE CG83 has been successful in profiling the importance of rehabilitation for survivors of critical illness. However, 4 years following publication of CG83 there has been limited development of this clinical service across the UK. Strategies to support delivery of such quality improvement programmes are urgently required to enhance patient care.

Neural respiratory drive in patients with COPD during exercise tests.

BACKGROUND: It is unknown whether neural drive is comparable in constant rate and incremental exercise tests. Few data have previously been available to address this question because of the lack of reliable methods to assess neural respiratory drive in patients with chronic obstructive pulmonary disease (COPD). OBJECTIVES: The aims of this study are to determine whether neural respiratory drive during constant rate exercise differs from that during incremental exercise and to determine whether neural respiratory drive was maximal at the end of exhaustive exercise tests. METHODS: We studied sixteen patients with moderate-severe COPD (mean ± SD FEV(1) 29 ± 10%). Both diaphragmatic electro-myogram (EMG) and transdiaphragmatic pressure were recorded with a combined multipair electrode balloon catheter during incremental and constant (80% of maximal oxygen consumption derived from a prior incremental exercise test) treadmill exercise. Minute ventilation and oxygen uptake were also measured. RESULTS: Root mean square (RMS) of the diaphragmatic EMG increased gradually without a plateau during incremental exercise, whereas the RMS increased initially and reached a plateau during constant work rate exercise. The RMS of the diaphragmatic EMG at the end of exercise was similar for both incremental and constant work rate exercise (176 ± 42 µV vs. 184 ± 39 µV); these values were 70 and 73% of maximal values recorded over the study. CONCLUSIONS: The pattern of increase in neural respiratory drive during incremental exercise is different to that observed during constant work rate exercise, but both exercise protocols are terminated when the patients achieve a similar but submaximal drive.

Screening for sleep-disordered breathing in neuromuscular disease using a questionnaire for symptoms associated with diaphragm paralysis.

Patients with neuromuscular disease (NMD) are at risk of developing sleep-disordered breathing (SDB) following respiratory muscle involvement. We hypothesised that a questionnaire based on clinical symptoms and signs of diaphragm weakness can be used to screen for SDB in such patients. We developed a self-administered multiple choice questionnaire containing five questions (Sleep-Disordered Breathing in Neuromuscular Disease Questionnaire (SiNQ)-5), scoring 0-10 points. 125 patients were enrolled: 32 with respiratory muscle weakness, 35 subjects with normal respiratory muscle strength and 58 patients with obstructive sleep apnoea (OSA). All subjects underwent full polysomnography. NMD patients with involvement of the respiratory muscles scored mean ± sd 6.8 ± 2.3 out of 10 points, significantly higher than both OSA patients 2.5 ± 2.3 and normal subjects 1.0 ± 2.0 (p < 0.001). A score of five or more points in the SiNQ-5 had a sensitivity of 86.2%, specificity of 88.5%, positive predictive value of 69.4% and a negative predictive value of 95.5% to identify NMD with combined SDB. A short self-administered questionnaire, the SiNQ-5, based on clinical symptoms can reliably screen for SDB in patients with diaphragm weakness. However, comorbidities, such as heart failure, that have symptoms influenced by posture could alter diagnostic accuracy.

Acute ischaemic hemispheric stroke is associated with impairment of reflex in addition to voluntary cough.

Cough function is impaired after stroke; this may be important for protection against chest infection. Reflex cough (RC) intensity indices have not been described after stroke. RC, voluntary cough (VC) and respiratory muscle strength were studied in patients within 2 weeks of hemispheric infarct. The null hypotheses were that patients with cortical hemisphere stroke would show the same results as healthy controls on: 1) objective indices of RC and VC intensity; and 2) respiratory muscle strength tests. Peak cough flow rate (PCFR) and gastric pressure (P(ga)) were measured during maximum VC and RC. Participants also underwent volitional and nonvolitional respiratory muscle testing. Nonvolitional expiratory muscle strength was assessed by measuring P(ga) increase after magnetic stimulation over the T10 nerve roots (twitch T10 P(ga)). Stroke severity was scored using the National Institutes of Health Stroke Scale (NIHSS; maximum = 31). 18 patients (mean ± sd age 62 ± 15 yrs and NIHSS score 14 ± 8) and 20 controls (56 ± 16 yrs) participated. VC intensity was impaired in patients (PCFR 287 ± 171 versus 497 ± 122 L·min⁻¹) as was VC P(ga) (98.5 ± 61.6 versus 208.5 ± 61.3 cmH2O; p < 0.001 for both). RC PCFR was reduced in patients (204 ± 111 versus 379 ± 110 L·min⁻¹; p < 0.001), but RC P(ga) was not significantly different from that of controls (179.0 ± 78.0 versus 208.0 ± 77.4 cmH2O; p = 0.266). Patients exhibited impaired volitional respiratory muscle tests, but twitch T10 P(ga) was normal. VC and RC are both impaired in hemispheric stroke patients, despite preserved expiratory muscle strength. Cough coordination is probably cortically modulated and affected by hemispheric stroke.

Neural respiratory drive in obesity.

BACKGROUND: The load imposed on ventilation by increased body mass contributes to the respiratory symptoms caused by obesity. A study was conducted to quantify ventilatory load and respiratory drive in obesity in both the upright and supine postures. METHODS: Resting breathing when seated and supine was studied in 30 obese subjects (mean (SD) body mass index (BMI) 42.8 (8.6) kg/m(2)) and 30 normal subjects (mean (SD) BMI 23.6 (3.7) kg/m(2)), recording the electromyogram of the diaphragm (EMGdi, transoesophageal multipair electrode), gastric and oesophageal pressures. RESULTS: Ventilatory load and neural drive were higher in the obese group as judged by the EMGdi (21.9 (9.0) vs 8.4 (4.0)%max, p<0.001) and oesophageal pressure swings (9.6 (2.9) vs 5.3 (2.2) cm H(2)O, p<0.001). The supine posture caused an increase in oesophageal pressure swings to 16.0 (5.0) cm H(2)O in obese subjects (p<0.001) and to 6.9 (2.0) cm H(2)O in non-obese subjects (p<0.001). The EMGdi increased in the obese group to 24.7 (8.2)%max (p<0.001) but remained the same in non-obese subjects (7.0 (3.4)%max, p = NS). Obese subjects developed intrinsic positive end-expiratory pressure (PEEPi) of 5.3 (3.6) cm H(2)O when supine. Applying continuous positive airway pressure (CPAP) in a subgroup of obese subjects when supine reduced the EMGdi by 40%, inspiratory pressure swings by 25% and largely abolished PEEPi (4.1 (2.7) vs 0.8 (0.4) cm H(2)O, p = 0.009). CONCLUSION: Obese patients have substantially increased neural drive related to BMI and develop PEEPi when supine. CPAP abolishes PEEPi and reduces neural respiratory drive in these patients. These findings highlight the adverse respiratory consequences of obesity and have implications for the clinical management of patients, particularly where the supine posture is required.

Neural drive during continuous positive airway pressure (CPAP) and pressure relief CPAP.

BACKGROUND: Pressure release continuous positive airway pressure (CPAP) is an evolution of CPAP that has been reported to improve patient comfort. We hypothesised the pressure release would lead to unloading of the inspiratory muscles and therefore conducted a prospective double-blind cross-over physiological study of autotitrating CPAP (APAP) against autotitrating pressure relief CPAP (PR-APAP). METHODS: Eleven patients with severe obstructive sleep apnoea (OSA; mean AHI 74.5+/-14.4/h) were studied. We assessed neural drive by recording the oesophageal pressure, gastric pressure, transdiaphragmatic pressure and the diaphragm EMG during overnight polysomnography. RESULTS: Both APAP and PR-APAP significantly reduced neural respiratory drive. Transdiaphragmatic pressure swings during apnoea (30.2+/-11.5 cm H2O) before treatment decreased to 9.1+/-5.3 cm H2O for PR-APAP and 8.5+/-3.7 cm H2O for APAP. The transdiaphragmatic pressure and the diaphragm EMG did not differ significantly between APAP and PR-APAP. The gastric pressure swing at expiration phase disappeared during both APAP and PR-APAP when sleep respiratory events were eliminated. CONCLUSIONS: PR-APAP is not superior to APAP in terms of reducing neural respiratory drive. It is unnecessary to replace conventional APAP with PR-APAP for patients who have been successfully treated with traditional APAP.

Ultrasound measurement of rectus femoris cross-sectional area and the relationship with quadriceps strength in COPD.

BACKGROUND: Quadriceps weakness and loss of muscle mass predict mortality in chronic obstructive pulmonary disease (COPD). It was hypothesised that a reduced quadriceps cross-sectional area could be detected by ultrasound in patients with COPD compared with healthy subjects, and that measurements relate to strength and fat-free mass (FFM). METHODS: Rectus femoris muscle cross-sectional area (RF(CSA)) was measured by ultrasound and whole-body FFM estimated using electrical bioimpedance. Quadriceps strength was measured by maximum voluntary contraction and twitch tension (TwQ) following magnetic femoral nerve stimulation. RESULTS: 26 healthy volunteers of mean (SD) age 63 (9) years and 30 patients with COPD of mean (SD) age 67 (9) years and percentage predicted forced expiratory volume in 1 s (FEV(1)) 48.0 (20.8)% with a similar FFM (46.9 (9.3) kg vs 46.1 (7.3) kg, p = 0.193) participated in the study. Mean RF(CSA) was reduced in patients with COPD by 25% of the mean value in healthy subjects(-115 mm(2); 95% CI -177 to -54, p = 0.001) and was related to MRC dyspnoea scale score, independent of FFM or sex. Maximum voluntary contraction strength was linearly related to RF(CSA) in patients with COPD (r = 0.78, p<0.001). TwQ force per unit of RF(CSA) was similar in both healthy individuals and those with COPD (mean (SD) 17 (4) g/mm(2) vs 18 (3) g/mm(2), p = 0.657). Voluntary contraction strength per unit of RF(CSA) was dependent on central quadriceps activation and peripheral oxygen saturation in COPD. CONCLUSION: Ultrasound measurement of RF(CSA) is an effort-independent and radiation-free method of measuring quadriceps muscle cross-sectional area in patients with COPD that relates to strength.

Neural respiratory drive in healthy subjects and in COPD.

The aim of the present study was to use the diaphragm electromyogram (EMG(di)) to compare levels of neural respiratory drive (NRD) in a cohort of healthy subjects and chronic obstructive pulmonary disease (COPD) patients, and to investigate the relationship between NRD and pulmonary function in COPD. EMG(di) was recorded at rest and normalised to peak EMG(di) recorded during maximum inspiratory manoeuvres (EMG(di) % max) in 100 healthy subjects and 30 patients with COPD, using a multipair oesophageal electrode. EMG(di) was normalised to the amplitude of the diaphragm compound muscle action potential (CMAP(di,MS)) in 64 healthy subjects. The mean+/-sd EMG(di) % max was 9.0+/-3.4% in healthy subjects and 27.9+/-9.9% in COPD patients, and correlated with percentage predicted forced expiratory volume in one second, vital capacity and inspiratory capacity in patients. EMG(di) % max was higher in healthy subjects aged 51-80 yrs than in those aged 18-50 yrs (11.4+/-3.4 versus 8.2+/-2.9%, respectively). Observations in the healthy group were similar when peak EMG(di) or CMAP(di,MS) were used to normalise EMG(di). Levels of neural respiratory drive were higher in chronic obstructive pulmonary disease patients than healthy subjects, and related to disease severity. Diaphragm compound muscle action potential could be used to normalise diaphragm electromyogram if volitional inspiratory manoeuvres could not be performed, allowing translation of the technique to critically ill and ventilated patients.

Sleep-disordered breathing in unilateral diaphragm paralysis or severe weakness.

Few data exist concerning sleep in patients with hemidiaphragm paralysis or weakness. Traditionally, such patients are considered to sustain normal ventilation in sleep. In the present study, diaphragm strength was measured in order to identify patients with unilateral paralysis or severe weakness. Patients underwent polysomnography with additional recordings of the transoesophageal electromyogram (EMG) of the diaphragm and surface EMG of extra-diaphragmatic respiratory muscles. These data were compared with 11 normal, healthy subjects matched for sex, age and body mass index (BMI). In total, 11 patients (six males, mean+/-sd age 56.5+/-10.0 yrs, BMI 28.7+/-2.8 kg x m(-2)) with hemidiaphragm paralysis or severe weakness (unilateral twitch transdiaphragmatic pressure 3.3+/-1.7 cmH(2)O (0.33+/-0.17 kPa) were studied. They had a mean+/-sd respiratory disturbance index of 8.1+/-10.1 events x h(-1) during non-rapid eye movement (NREM) sleep and 26.0+/-17.8 events x h(-1) during rapid eye movement (REM) sleep (control groups 0.4+/-0.4 and 0.7+/-0.9 events x h(-1), respectively). The diaphragm EMG, as a percentage of maximum, was double that of the control group in NREM sleep (15.3+/-5.3 versus 8.9+/-4.9% max, respectively) and increased in REM sleep (20.0+/-6.9% max), while normal subjects sustained the same level of activation (6.2+/-3.1% max). Patients with unilateral diaphragm dysfunction are at risk of developing sleep-disordered breathing during rapid eye movement sleep. The diaphragm electromyogram, reflecting neural respiratory drive, is doubled in patients compared with normal subjects, and increases further in rapid eye movement sleep.

Neural respiratory drive during apnoeic events in obstructive sleep apnoea.

For a given neural drive, oesophageal pressure during apnoeic episodes may differ from that during airflow, since inspiratory airflow and increased lung volume both reduce pressure generation. It was, therefore, hypothesised that diaphragm electromyography (EMG) may provide additional data to oesophageal pressure when used for the assessment of neural drive in patients with obstructive sleep apnoea, whose breathing is associated with variable airflow and changes in lung volume. Neural respiratory drive was assessed using diaphragm EMG recorded from multipair oesophageal electrodes in 12 patients with obstructive sleep apnoea. Oesophageal pressure was also recorded. The mean+/-sd inspiratory oesophageal pressure swing was 11.0+/-3.7 cmH(2)O during wakefulness, 38.2+/-15.7 cmH(2)O at the end of the apnoea and reduced to 28.5+/-10.4 cmH(2)O at the beginning of arousal. The mean peak inspiratory diaphragm EMG signal was 21.8+/-6.5 muV during wakefulness, 38.6+/-14.0 muV at the end of the apnoea and further increased to 59.6+/-32.0 muV at the beginning of arousal. It was concluded that the pattern of neural drive assessed by oesophageal pressure differs from that measured by diaphragm electromyography during apnoeic events and, therefore, that diaphragm electromyography may be a useful adjunct to measurement of oesophageal pressure for the assessment of neural drive in patients with obstructive sleep apnoea.

Optical feedback training of inhalation with Autohaler and Turbuhaler in COPD patients.

The success of inhalation therapy depends on patients inhalation technique and correct handling of the inhalation device. In this study the effort to train correct handling and optimal inhalation technique of patients using Autohaler and Turbuhaler was assessed. The Bad-Reichenhall-Aerosol-Therapy-Trial (BREATH) was a prospective, randomized, cross-over trial in 200 patients who were not familiar with either of the test systems. The correct handling of Autohaler and Turbuhaler was assessed by means of a checklist (observation score). An optimal inhalation maneuver was used evaluated with the computer-based Inhalation Manager (optical feedback, computer score). The Autohaler reached 6.58 +/- 3.64 (mean +/- SD) out of nine points in the observation score and 66.85 +/- 29.84% in the computer score before training. After training the scores increased significantly to 8.33 +/- 2.08 points and 86 +/- 23.40% respectively. The use of the Turbuhaler also significantly improved from 4.28 +/- 4.24 points and 56.67 +/- 42.97% to 7.78 +/- 2.74 points and 85.80 +/- 27.63%, respectively. The significant improvement of patients inhalation technique after training emphasizes the importance of training in inhalation therapy. In addition, it could be demonstrated that the optical feedback given by the Inhalation Manager was a useful tool for improving the inhalation technique of patients using Autohaler and Turbuhaler.

[Physical therapy in COPD--Evidence based medicine?]. / Physikalische Therapie bei COPD - Evidence Based Medicine?

Several therapeutical options of physical therapy in COPD show significant effects on the organism. Some of those effects are verified, but there is still an uncertainty about the exact influences on the disease and the beneficial outcome, especially because different trials describe contradictory results. Existing studies observed an improved respiratory mechanism with a more economical ventilatory work and a better gas exchange by use of physical therapy. Therefore the right indication for certain options of physical therapy should be defined, so that the outcome can be controlled and a benefit can be drawn from the effects. Sufficient data of existing trials for the whole physical therapy in COPD is still deficient. Due to an inappropriate study design and/or the number of observed patients a lot of clinical studies are not qualified to lead to significant results and recommendations. For the future it is necessary to investigate the exact effects of physical therapy with controlled, randomised, clinical trials further on. Hereby an improvement of the care of patients with COPD can be achieved and the beneficial effects and the outcome with physical therapy can better be estimated.

Correlation between fetal sex and human chorionic gonadotropin in peripheral maternal blood and amniotic fluid in second and third trimester normal pregnancies.

BACKGROUND: To study the correlation between fetal sex and human chorionic gonadotropin (hCG) in maternal blood and amniotic fluid. METHOD AND MATERIAL: One hundred and thirty uncomplicated pregnancies, 82 of whom were at sixteen and 48 at thirty-five weeks of gestation. RESULTS: The hCG levels were significantly higher in maternal serum than in amniotic fluid. At 16 weeks there were no sex-related differences in the hCG levels, either in maternal blood or in amniotic fluid. At 35 weeks the hCG levels in maternal blood were significantly higher in pregnancies with female fetuses than in those carrying male fetuses (p<0.004), while in amniotic fluid the hCG levels tended to be slightly higher in the female group than in the male. In pregnancies with female fetuses the hCG levels in maternal blood were significantly higher at 35 than at 16 weeks (p<0.02), while in pregnancies with male fetuses the levels were highest at 16 weeks. For both sexes the hCG levels in amniotic fluid were significantly higher at 16 than at 35 weeks of pregnancy (p<0.001). Whereas a significant correlation between hCG levels in maternal blood and amniotic fluid was seen at 16 weeks of gestation for both sexes (p<0.01 and R value 0.45 for males and 0.41 for females), no correlation was observed at 35 weeks. CONCLUSION: This study shows a significant correlation between hCG and fetal sex at third trimester of gestation only, possibly caused by a gender factor and a shift in synthesis and/or in metabolism of hCG from the second to the third trimester.

[To conceive a child is not a human right]. / A få barn er ingen menneskerett.

PIP: In recent decades, with the help of in vitro fertilization and freezing of pre-embryos, the reproductive limits have been extended for infertile couples. Such techniques also confirm severe genetic diseases in advance and help decide on abortion. In Norway it is still a paradox that, even though so much knowledge has been acquired about reproduction and the means of regulating it, annually about 15,000 healthy fetuses are aborted when there are couples who would do anything to have children. Women have different reasons why they never became pregnant, and when they come to the end of their reproductive age they find it important to have a child. The reproduction of women differs from that of men because the latter still can produce sperm in old age, while the optimal age for women to become pregnant is in the mid-20s. 80% of them become pregnant within 1 year at this age, but starting at age 30 there is a gradual reduction in the ability to conceive. At age 40 only 30-40% of women become pregnant within 1 year. The risk of having a genetic defect also increases with age. At an older age the risks of infections, hormonal disorders, and the development of malignancies also increase. Other factors that influence reproduction include stress, physical exertion over time producing amenorrhea, carrier goals with physical and psychological demands, and sexually active life leading to infections. Women should realize that their biological age for conception is preordained and should use the best time to have a child. In this area of problem resolution, doctors can be instrumental by providing advice and counseling, especially when the couple has a functional defect which hinders spontaneous pregnancy.^ieng

Human chorionic gonadotropin in cord blood and peripheral maternal blood in singleton and twin pregnancies at delivery.

The influence of fetal sex on human chorionic gonadotropin (hCG) in cord and peripheral maternal blood was studied at delivery in 57 twin and 66 singleton uncomplicated pregnancies. In twin pregnancies the hCG levels were about twice as high in female-female and in female-male vis-à-vis male-male combinations in both maternal and cord blood. In singleton pregnancies the hCG levels were significantly higher in maternal and in cord blood in cases of female vis-à-vis male infants. The ratio of maternal hCG/placental weight was also highest in the twin pregnancies when one or both infants were female. This suggests a "female effect", possibly genetically based.

Ovarian pregnancy associated with the intra-uterine contraceptive device. A survey of two decades.

Records of 25 cases of ovarian pregnancy in the period 1965 to 1984 were reviewed. Seventeen cases (68%), had an IUCD in situ, and 15 of these had occurred during the last decade. The ratio of ovarian pregnancy to all ectopic pregnancies was 1:13 in the IUCD group versus 1:78 in the non-IUCD group (p less than 0.025). In contrast to patients with tubal pregnancies, those with ovarian pregnancy very seldom have a history of pelvic inflammatory disease (PID), infertility, or earlier pelvic operations. Subsequent fertility is good compared with patients with tubal pregnancies, for patients both with and without IUCD.

Repeat ectopic pregnancy. A twenty-year hospital survey.

Seventy-two patients with repeat ectopic pregnancy including 3 women with three ectopic pregnancies each during the period 1965 to 1984 were studied. In the same period there was a total of 842 ectopic pregnancies, giving a repeat ectopic pregnancy incidence of 9.4%. In the last decade the incidence of repeat ectopic pregnancy was 10.4%, and in the first decade it was 7.0% (p less than 0.025). None of the women used an intra-uterine contraceptive device, among those with repeat ectopic pregnancy in the first decade, vis-à-vis 17 (30.4%) in the last decade. A history of infertility was common among the patients with repeat ectopic pregnancy. Between the two events there was a total of 17 deliveries in 13 patients. Four out of 24 potentially fertile women completed full-term pregnancies following their second ectopic pregnancy.