Effect of sex of fetus on asthma during pregnancy: blind prospective study

Abstract

(Accepted 11 June 1998)Effect of sex of fetus on asthma during pregnancy: blind prospective studyThe course of asthma during pregnancy is variable and may remain unchanged, worsen, or improve, returning to the pre-pregnancy state within three months after parturition.1 Some patients experience the same changes in each pregnancy, but nearly half do not, suggesting some intrinsic or extrinsic factor unique to each pregnancy such as the sex of the fetus. 1 We observed that the condition of patients with moderate to severe asthma generally deteriorated when they were pregnant with girls but not boys, raising the intriguing possibility that the sex of the fetus might influence the course of asthma during pregnancy. We investigated this possibility in a blind prospective study. Subjects, methods, and resultsAll women aged 25-34 who were receiving regular drug treatment for asthma and were in the second trimester of pregnancy (12-21 weeks' gestation) were approached directly to participate in the study. Twenty eight women were recruited from three hospital and four general practice antenatal clinics and six from an asthma clinic. Twelve had not taken inhaled steroids (beclomethasone or budesonide) regularly before pregnancy, 16 took 200-500 g daily, and six more than 500 g daily. None was taking oral steroids. None knew the sex of their baby before delivery. The study took the form of a questionnaire on symptoms of asthma, cough, shortness of breath, nocturnal waking due to asthma, drug treatment (frequency and amount), and visits to a doctor for asthma before and since the beginning of pregnancy, a minimum period of 12 weeks. Subjects were also asked to keep daily diary cards and peak expiratory flow readings throughout pregnancy. All 34 subjects completed the questionnaire; only 15 agreed to keep daily records and only 6 successfully completed these. We have therefore based our analysis on the questionnaire alone. Subjects were contacted again after parturition to ascertain the sex of the baby.Eighteen women had boys and 16 girls. There was no difference in age range of mothers, gestation at time Papers

Perinatal outcomes following maternal asthma and cigarette smoking during pregnancy

“…Together, these data indicate that the adverse perinatal outcomes observed in the current cohort are not specific to the most severe cases (including asthma exacerbations) of asthma. Despite evidence indicating that females carrying a female fetus experience a deterioration of asthma symptoms, as well as an increased requirement for medication and increased circulating monocytes in pregnancy [28,[46][47][48][49], most previous studies failed to consider the sex of the infant in their analyses. In the current study, a sex-specific association was demonstrated, with the risk of SGA increased in male but not female neonates in pregnancies of females with asthma.…”

Sexually dimorphic effects of maternal asthma during pregnancy on placental glucocorticoid metabolism and fetal growth

“…The sex of the fetus may be one factor contributing to worsening asthma during pregnancy. A number of recent studies have reported that the presence of a female fetus is associated with worsening maternal asthma and increased requirement for inhaled steroid treatment (Dodds et al 1999;Beecroft et al 1998;Murphy et al 2003). Murphy et al (2003) have reported that circulating monocyte concentrations increase in asthmatic women who avoid the use of inhaled glucocorticoids during pregnancy and are pregnant with a female fetus.…”

Asthma during pregnancy: mechanisms and treatment implications

“…In a blind prospective study, BEECROFT et al [99] studied 34 pregnant mothers with moderate or severe asthma who were using regular treatments. Significantly more mothers pregnant with a female foetus reported shortness of breath, nocturnal waking and a worsening of cough and asthma in general, while mothers pregnant with a male foetus were more likely to report an improvement in asthma [99].…”

“…In a blind prospective study, BEECROFT et al [99] studied 34 pregnant mothers with moderate or severe asthma who were using regular treatments. Significantly more mothers pregnant with a female foetus reported shortness of breath, nocturnal waking and a worsening of cough and asthma in general, while mothers pregnant with a male foetus were more likely to report an improvement in asthma [99]. DODDS et al [103] reported that re-analysis of their Canadian population-based study indicated that fewer asthmatic subjects pregnant with a male foetus required steroids for treatment (14%), compared with asthmatic subjects pregnant with a female foetus (20%) [1].…”