Asthma and/or hay fever as predictors of fertility/impaired fecundity in U.S. women: National Survey of Family Growth

Infertility, pregnancy loss and assisted reproduction in women with asthma: a population-based cohort study

STUDY QUESTION

Is the chance of childbirth, and risk of infertility, pregnancy loss and need for assisted reproduction different for women with asthma compared to women without asthma?

SUMMARY ANSWER

Women with asthma had comparable chances of giving birth compared to the reference population, however, their risk of both infertility and pregnancy loss, as well their need for medically assisted reproduction, was higher.

WHAT IS KNOWN ALREADY

Reproductive dysfunction has been reported among women with asthma, including longer time to pregnancy, increased risk of pregnancy loss and a higher need of medically assisted reproduction, but their risk of clinical infertility is unknown.

STUDY DESIGN, SIZE, DURATION

This longitudinal register-based cohort study included all women with a healthcare visit for delivery, infertility, pregnancy loss or induced abortion in the southernmost county in Sweden, over the last 20 years.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Using the Skåne Healthcare Register, we identified all women aged 15-45 between 1998 and 2019, who received a diagnosis of asthma before their first reproductive outcome (n = 6445). Chance of childbirth and risk of infertility, pregnancy loss and assisted reproduction were compared to a healthcare seeking population of women without any asthma (n = 200 248), using modified Poisson regressions.

MAIN RESULTS AND THE ROLE OF CHANCE

The chance of childbirth was not different between women with asthma versus those without, adjusted risk ratio (aRR) = 1.02, 95% CI: 1.01-1.03. The risk of seeking care for infertility was increased, aRR = 1.29, 95% CI: 1.21-1.39, and women with asthma more often needed assisted reproduction aRR = 1.34 95% CI: 1.18-1.52. The risk of suffering a pregnancy loss was higher, aRR = 1.21, 95% CI: 1.15-1.28, and induced abortions were more common, aRR = 1.15, 95% CI: 1.11-1.20, among women with asthma.

LIMITATIONS, REASONS FOR CAUTION

The study was an observational study based on healthcare visits and lacked detailed anthropometric data, thus residual confounding cannot be excluded. Only women with a healthcare visit for a reproductive outcome were included, which cannot be translated into pregnancy intention. A misclassification, presumed to be non-differential, may arise from an incorrect or missing diagnosis of asthma or female infertility, biasing the results towards the null.

WIDER IMPLICATIONS OF THE FINDINGS

This study points towards reproductive dysfunction associated with asthma, specifically in regards to the ability to maintain a pregnancy and the risk of needing medically assisted reproduction following clinical infertility, but reassuringly the chance of subsequently giving birth was not lower for these women.

STUDY FUNDING/COMPETING INTEREST(S)

This article is part of the ReproUnion collaborative study, co-financed by EU Interreg ÖKS, Capital Region of Denmark, Region Skåne and Ferring Pharmaceuticals. The authors have no competing interests to disclose.

TRIAL REGISTRATION NUMBER

N/A.

Association between Low House Cleaning Frequency, Cough and Risk of Miscarriage: A Case Control Study in China

This study investigated the association between house cleaning frequency and the risk of miscarriage in a case control sample of Chinese population. We recruited 59 pregnant women with clinical pregnancy loss as cases and 122 women who chose to conduct induced abortion as controls. All participants were aged 20~40 years and completed a questionnaire of lifestyle exposure with a trained nurse. The effect of frequency of cleaning up on risk of miscarriage was estimated using multivariable logistic regressions, adjusting for potential confounders. In the present study, it was shown that house cleaning of less than twice per week was significantly associated with cough during day or night with odds ratio (OR) of 2.97 (95% CI: 1.36~6.75, p = 0.007), and cough during day or night was significantly associated with risk of miscarriage with OR of 2.69 (95% CI: 1.22~6.02, p = 0.014). Thus, house cleaning of less than twice per week was statistically significantly associated with miscarriage with OR of 3.05 (95% CI: 1.51~6.31, p = 0.002). We found that females who have their house cleaned less than twice per week are at elevated risk for miscarriage. Therefore, the home of pregnant woman should be cleaned at least twice per week in order to avoid miscarriage.

Potential causes of male and female infertility in Qatar

A steady decline in the fertility rate has been observed in Qatar during the past fifty years. Therefore, infertility is considered a national priority in Qatar, a pronatalist society. This review article summarises the potential causes of infertility that are particularly prevalent in the Qatari population. The high rate of consanguinity leading to genetic abnormalities, the high incidence of metabolic disease, environmental contamination due to the rapid urbanization and oil and natural gas extraction procedures are discussed. In addition, the particular lifestyle of the Qatari population and the influence of religion and culture on sexual and reproductive behavior in an Arab/Islamic society are considered. The active response of the state of Qatar in implementing ways to mitigate the effects of these factors to protect fertility are also presented.