Maternal age at delivery, lung function and asthma in offspring: a population-based survey

There is limited information about potential impact of maternal age on the respiratory health of offspring. We investigated the association of maternal age at delivery with adult offspring's lung function, respiratory symptoms and asthma, and potential differences according to offspring sex. 10 692 adults from 13 countries participating in the European Community Respiratory Health Survey (ECRHS) II responded to standardised interviews and provided lung function measurements and serum for IgE measurements at age 25–55 years. In logistic and linear multilevel mixed models we adjusted for participants’ characteristics (age, education, centre, number of older siblings) and maternal characteristics (smoking in pregnancy, education) while investigating for differential effects by sex. Maternal age was validated in a subsample using data from the Norwegian birth registry. Increasing maternal age was associated with increasing forced expiratory volume in 1 s (2.33 mL per year, 95% CI 0.34–4.32 mL per year), more consistent in females (ptrend 0.025) than in males (ptrend 0.14). Asthma (OR 0.85, 95% CI 0.79–0.92) and respiratory symptoms (OR 0.87, 95% CI 0.82–0.92) decreased with increasing maternal age (per 5 years) in females, but not in males (pinteraction 0.05 and 0.001, respectively). The results were consistent across centres and not explained by confounding factors. Maternal ageing was related to higher adult lung function and less asthma/symptoms in females. Biological characteristics in offspring related to maternal ageing are plausible and need further investigation

How Do Cord Compressions Affect the Umbilical Venous Flow Resistance? An In Vitro Investigation of the Biomechanical Mechanisms

Umbilical vessels, that provide blood oxygenation and fetal nourishment in utero, are encased and protected against external forces by the umbilical cord. The biomechanics of this peculiar structure has not been deeply investigated so far. The purpose of this study is to investigate the hydraulic behaviour of human umbilical veins (UV) and its changes in presence of an external cord compression. Five umbilical cords were subjected to in vitro tests. UV was accurately cannulated and connected to a perfusion circuit, while the cord was subjected to an external compression. Pressure drops across UV were measured for various venous flow rates and various degrees of cord constriction. Compressive forces were measured, too. The UV hydraulic resistances measured in unloaded cords (0.029 ± 0.016 mmHg min cm-1 L-1) correspond to placenta-abdomen pressure drops well consistent with in utero measurements. As expected, at fixed flow rate, flow resistance augments when cord is compressed. Interestingly, resistance does not substantially change until a 30-50% cord thickness reduction, whereas slightly larger constriction cause a steep increase. Compressive forces becomes critical for values above 0.5-2 N, depending on the length of cord compression and on considered specimen. Moreover, at high cord constriction, hydraulic behaviour of UV is very peculiar. Namely, the slope of the pressure-flow relationship decreases at increasing flow rates and, in few cases, a surprising reduction of pressure drop was even observed. The biomechanical behaviour of the umbilical cord during compression is very complex, with high non-linearity of venous hydraulic behaviour

Father’s environment before conception and asthma risk in his children: a multi-generation analysis of the Respiratory Health in Northern Europe study

BACKGROUND: Whereas it is generally accepted that maternal environment plays a key role in child health, emerging evidence suggests that paternal environment before conception also impacts child health. We aimed to investigate the association between children's asthma risk and parental smoking and welding exposures prior to conception. METHODS: In a longitudinal, multi-country study, parents of 24 168 offspring aged 2-51 years provided information on their life-course smoking habits, occupational exposure to welding and metal fumes, and offspring's asthma before/after age 10 years and hay fever. Logistic regressions investigated the relevant associations controlled for age, study centre, parental characteristics (age, asthma, education) and clustering by family. RESULTS: Non-allergic early-onset asthma (asthma without hay fever, present in 5.8%) was more common in the offspring with fathers who smoked before conception {odds ratio [OR] = 1.68 [95% confidence interval (CI) = 1.18-2.41]}, whereas mothers' smoking before conception did not predict offspring asthma. The risk was highest if father started smoking before age 15 years [3.24 (1.67-6.27)], even if he stopped more than 5 years before conception [2.68 (1.17-6.13)]. Fathers' pre-conception welding was independently associated with non-allergic asthma in his offspring [1.80 (1.29-2.50)]. There was no effect if the father started welding or smoking after birth. The associations were consistent across countries. CONCLUSIONS: Environmental exposures in young men appear to influence the respiratory health of their offspring born many years later. Influences during susceptible stages of spermatocyte development might be important and needs further investigation in humans. We hypothesize that protecting young men from harmful exposures may lead to improved respiratory health in future generations