Parental Infertility, Fertility Treatment, and Childhood Epilepsy: A Population-Based Cohort Study

Long-term health risk of offspring born from assisted reproductive technologies

Since the world's first in vitro fertilization baby was born in 1978, there have been more than 8 million children conceived through assisted reproductive technologies (ART) worldwide, and a significant proportion of them have reached puberty or young adulthood. Many studies have found that ART increases the risk of adverse perinatal outcomes, including preterm birth, low birth weight, small size for gestational age, perinatal mortality, and congenital anomalies. However, data regarding the long-term outcomes of ART offspring are limited. According to the developmental origins of health and disease theory, adverse environments during early life stages may induce adaptive changes and subsequently result in an increased risk of diseases in later life. Increasing evidence also suggests that ART offspring are predisposed to an increased risk of non-communicable diseases, such as malignancies, asthma, obesity, metabolic syndrome, diabetes, cardiovascular diseases, and neurodevelopmental and psychiatric disorders. In this review, we summarize the risks for long-term health in ART offspring, discuss the underlying mechanisms, including underlying parental infertility, epigenetic alterations, non-physiological hormone levels, and placental dysfunction, and propose potential strategies to optimize the management of ART and health care of parents and children to eliminate the associated risks. Further ongoing follow-up and research are warranted to determine the effects of ART on the long-term health of ART offspring in later life.

Risk of febrile seizures among children conceived following fertility treatment: A cohort study

BACKGROUND

Studies have shown that fertility treatment in mothers is associated with neurological problems in children. However, knowledge about any association between maternal use of fertility treatment and febrile seizures in children is lacking.

OBJECTIVE

To determine whether maternal use of fertility treatment is associated with febrile seizures in children.

METHODS

All liveborn children in Denmark during 1996-2012 (n = 1 065 901) were linked with the Danish Infertility Cohort and the Danish national registers and were followed from one year of age until the first episode of a febrile seizure, death, emigration, loss to follow-up, or end of follow-up (December 2015). Cox proportional hazard regression was used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) with adjustment for potential confounders.

RESULTS

Approximately 16% children (n = 172 140) were conceived by infertile women, and approximately 3% (n = 34 082) were diagnosed with febrile seizures during follow-up. Compared with children conceived by fertile women, children conceived following any fertility treatment (HR 1.11, 95% CI 1.06, 1.16), following specific fertility treatment, for example IVF (HR 1.15, 95% CI 1.05, 1.25), ICSI (HR 1.20, 95% CI 1.10, 1.32), and following fertility drugs (HR 1.06, 95% CI 1.00, 1.11) had slight increase in risk of febrile seizures, after adjusting for calendar year of birth, parental age, education, parity status, and maternal smoking during pregnancy. The associations were unchanged when children conceived naturally by infertile women were used as the reference group.

CONCLUSIONS

Children conceived following fertility treatment had slightly increased relative risk for febrile seizures.

Lifestyle in pregnancy and cryptorchidism in sons: a study within two large Danish birth cohorts

Purpose

Cryptorchidism is the most frequent congenital malformation in boys and is associated with low sperm count, infertility and testicular cancer. Unhealthy maternal lifestyle during pregnancy such as smoking, high prepregnancy body mass index (BMI) as well as alcohol and caffeine intake may constitute possible risk factors for cryptorchidism, but results from the few previous studies are conflicting. We aimed to explore the association between maternal lifestyle factors and occurrence of cryptorchidism in sons.

Patients and methods

The Danish National Birth Cohort and the Aarhus Birth Cohort provided information on maternal lifestyle from early pregnancy. Data were linked to several Danish health registers, multiple imputation was used to handle missing data and Cox proportional hazards models were used to adjust for potential confounders.

Results

In total, 85,923 boys were included, and of them, 2.2% were diagnosed with cryptorchidism. We observed the strongest associations between maternal tobacco smoking and prepregnancy BMI and cryptorchidism. Sons of women who smoked 10–14 cigarettes/day had the highest hazard ratio (HR) for cryptorchidism (1.37; 95% CI: 1.06–1.76), and for maternal BMI ≥30 kg/m², the HR was 1.32 (95% CI: 1.06–1.65). Binge drinking was associated with an HR <1, if the women had one or two episodes in pregnancy (HR: 0.81; 95% CI: 0.67–0.98). Average maternal alcohol intake and caffeine intake during pregnancy were not significantly associated with a higher occurrence of cryptorchidism detected at birth or later in life.

Conclusion

Maternal tobacco smoking, overweight and obesity in pregnancy were associated with higher occurrence of cryptorchidism in boys in this study.