Do pregnant women report use of dispensed medications?

Drug use in pregnant women-a pilot study of the coherence between reported use of drugs and presence of drugs in plasma

Purpose

In Sweden, information on drug use during pregnancy is obtained through an interview and recorded in a standardized medical record at every visit to the antenatal care clinic throughout the pregnancy. Antenatal, delivery, and neonatal records constitute the basis for the Swedish Medical Birth Register (MBR). The purpose of this exploratory study was to investigate the reliability of reported drug use by simultaneous screening for drug substances in the blood stream of the pregnant woman and thereby validate self-reported data in the MBR.

Methods

Plasma samples from 200 women were obtained at gestational weeks 10–12 and 25 and screened for drugs by using ultra-high performance liquid chromatography with time of flight mass spectrometry (UHPLC-TOF-MS). The results from the analysis were then compared to medical records.

Results

At the first sampling occasion, the drugs found by screening had been reported by 86% of the women and on the second sampling, 85.5%. Missed reported information was clearly associated with drugs for occasional use. The most common drugs in plasma taken in early and mid-pregnancy were meclizine and paracetamol. Two types of continuously used drugs, selective serotonin reuptake inhibitors and propranolol, were used. All women using them reported it and the drug screening revealed a 100% coherence.

Conclusions

This study shows good coherence between reported drug intake and the drugs found in plasma samples, which in turn positively validates the MBR.

Prenatal exposure to antipsychotic medication and use of primary health care system in childhood: a population-based cohort study in Denmark

Background

Antipsychotic (AP) medication is increasingly used for many health conditions. Prenatal exposure to AP medication has been associated with several adverse outcomes, but the findings remain inconsistent.

Purpose

We aimed to investigate prenatal exposure to AP medication and the use of primary health care system in childhood.

Subjects and methods

All live-born singletons in Denmark during 1997-2012 were identified in the nationwide Danish National Patient Register and followed until December 31, 2013 (n = 963,010). Information on prenatal exposure to AP medication was obtained from the Danish Register of Medicinal Product Statistics. Contacts to the general practitioner (GP) were used as a proxy for the overall health of the children. Negative binomial regression was used to calculate incidence rate ratios (IRRs) and 95% confidence intervals (CIs) for the association between prenatal exposure to AP medication and number and type of GP contacts, excluding routine well-child visits and vaccinations. The models were adjusted for sex and birth date of the child, maternal age, parity, cohabitation status, income, education, smoking status, diagnosis of substance abuse, severe psychiatric disorder, depression and epilepsy as well as the use of antiepileptic drugs, antidepressants, benzodiazepines and insulin.

Results

The prenatally AP-exposed children had 7% more GP contacts than unexposed children, IRR: 1.07 (95% CI: 1.03, 1.11). The association was slightly stronger among children of mothers with no diagnosis of severe psychiatric disorder (IRR: 1.08, 95% CI: 1.04-1.13) than among children of mothers with severe psychiatric disorder (IRR: 1.03, 95% CI: 0.96-1.11), but the difference was not statistically significant. We found no difference between prenatally AP-exposed children and their unexposed siblings, IRR: 1.00 (95% CI: 0.97-1.04) for total contacts.

Conclusion

Children of women using AP medication in pregnancy had more GP contacts in childhood than children of mothers not using AP medication. However, this might be explained by confounding from maternal behavior and mental illness.

Antidepressant use during pregnancy and childhood cancer in the offspring

PURPOSE

Antidepressant use during pregnancy has been increasing in recent years. We evaluated whether in utero exposure to antidepressants increased the risk of childhood cancer.

METHODS

This population-based cohort study using national registers in Denmark comprised 915 128 liveborn singletons during 1998-2012. We categorised children into three mutually exclusive exposure groups according to maternal redemption of an antidepressant prescription from 2 years before pregnancy until delivery of the index child: Unexposed (N = 863 033), prior user (use before but not during pregnancy) (N = 30 607), and use during pregnancy (N = 21 488). The children were followed from birth until first diagnosis of cancer, death, emigration, or December 31, 2012, whichever came first. The children were followed maximum 14.9 years and contributed to 6.9 × 10⁶ person-years at risk. We estimated hazard ratios (HRs) of cancer using Cox regression with 95% confidence intervals (CIs).

RESULTS

In total, 1298 (0.1%) children were diagnosed with cancer. Antidepressant use during pregnancy was not associated with a significantly increased risk of childhood cancer in general; the HR was 1.03 (95% CI, 0.63-1.68), compared to children born by mothers who discontinued antidepressant use prior to pregnancy. The association between in utero exposure to antidepressants and childhood cancer did not depend on type or duration of antidepressant use. There was no strong evidence indicating a higher risk of leukaemia or nervous system tumours among children exposed to antidepressants in utero.

CONCLUSION

Antidepressant use during pregnancy was not significantly associated with childhood cancer in general nor with leukaemia or nervous system tumours in specific.

Birth defects after use of antithyroid drugs in early pregnancy: a Swedish nationwide study

OBJECTIVE

Antithyroid drugs (ATDs) may have teratogenic effects, but more evidence is needed on the risk and types of birth defects after the use of methimazole (MMI) and propylthiouracil (PTU). This study aimed to evaluate the association between the use of ATDs in early pregnancy and birth defects.

DESIGN

Swedish nationwide register-based cohort study.

METHODS

The study included 684 340 children live-born in Sweden from 2006 to 2012. Exposure groups defined by maternal ATD use in early pregnancy were MMI (n = 162); PTU (n = 218); MMI and PTU (n = 66); ATD before or after, but not in pregnancy (n = 1551) and non-exposed (never ATD (n = 682 343)). Outcome was cumulative incidence of birth defects diagnosed before two years of age.

RESULTS

The cumulative incidence of birth defects was not significantly different in children exposed to MMI (6.8%, P = 0.6) or PTU (6.4%, P = 0.4) vs non-exposed (8.0%). For subtypes of birth defects, MMI was associated with an increased incidence of septal heart defects (P = 0.02). PTU was associated with ear (P = 0.005) and obstructive urinary system malformations (P = 0.006). A case of choanal atresia was observed after exposure to both MMI and PTU. The incidence of birth defects in children born to mothers who received ATD before or after, but not in pregnancy, was 8.8% and not significantly different from non-exposed (P = 0.3), MMI exposed (P = 0.4) or PTU exposed (P = 0.2).

CONCLUSIONS

MMI and PTU were associated with subtypes of birth defects previously reported, but the frequency of ATD exposure in early pregnancy was low and severe malformations described in the MMI embryopathy were rarely observed.

Antidepressant use during pregnancy and psychiatric disorders in offspring: Danish nationwide register based cohort study

Objective To investigate the association between in utero exposure to antidepressants and risk of psychiatric disorders.Design Population based cohort study.Setting Danish national registers.Participants 905 383 liveborn singletons born during 1998-2012 in Denmark and followed from birth until July 2014, death, emigration, or date of first psychiatric diagnosis, whichever came first. The children were followed for a maximum of 16.5 years and contributed 8.1×10⁶ person years at risk.Exposures for observational studies Children were categorised into four groups according to maternal antidepressant use within two years before and during pregnancy: unexposed, antidepressant discontinuation (use before but not during pregnancy), antidepressant continuation (use both before and during pregnancy), and new user (use only during pregnancy).Main outcome measure First psychiatric diagnosis in children, defined as first day of inpatient or outpatient treatment for psychiatric disorders. Hazard ratios of psychiatric disorders were estimated using Cox regression models.Results Overall, psychiatric disorders were diagnosed in 32 400 children. The adjusted 15 year cumulative incidence of psychiatric disorders was 8.0% (95% confidence interval 7.9% to 8.2%) in the unexposed group, 11.5% (10.3% to 12.9%) in the antidepressant discontinuation group, 13.6% (11.3% to 16.3%) in the continuation group, and 14.5% (10.5% to 19.8%) in the new user group. The antidepressant continuation group had an increased risk of psychiatric disorders (hazard ratio 1.27, 1.17 to 1.38), compared with the discontinuation group.Conclusions In utero exposure to antidepressants was associated with increased risk of psychiatric disorders. The association may be attributable to the severity of underlying maternal disorders in combination with antidepressant exposure in utero. The findings suggest that focusing solely on a single psychiatric disorder among offspring in studies of in utero antidepressant exposure may be too restrictive.

Association Between Pregnancy and Perinatal Outcomes Among Women With Epilepsy

Importance

To date, few attempts have been made to examine associations between exposure to maternal epilepsy with or without antiepileptic drug (AED) therapy and pregnancy and perinatal outcomes.

Objectives

To investigate associations between epilepsy in pregnancy and risks of pregnancy and perinatal outcomes as well as whether use of AEDs influenced risks.

Design, Setting, and Participants

A population-based cohort study was conducted on all singleton births at 22 or more completed gestational weeks in Sweden from 1997 through 2011; of these, 1 424 279 were included in the sample. Information on AED exposure was available in the subset of offspring from July 1, 2005, to December 31, 2011. Data analysis was performed from October 1, 2016, to February 15, 2017.

Main Outcomes and Measures

Pregnancy, delivery, and perinatal outcomes. Multivariable Poisson log-linear regression was used to estimate adjusted risk ratios (aRRs) and 95% CIs, after adjusting for maternal age, country of origin, educational level, cohabitation with a partner, height, early pregnancy body mass index, smoking, year of delivery, maternal pregestational diabetes, hypertension, and psychiatric disorders.

Results

Of the 1 429 652 births included in the sample, 5373 births were in 3586 women with epilepsy; mean (SD) age at first delivery of the epilepsy cohort was 30.54 (5.18) years. Compared with pregnancies of women without epilepsy, women with epilepsy were at increased risks of adverse pregnancy and delivery outcomes, including preeclampsia (aRR 1.24; 95% CI, 1.07-1.43), infection (aRR, 1.85; 95% CI, 1.43-2.29), placental abruption (aRR, 1.68; 95% CI, 1.18-2.38), induction (aRR, 1.31; 95% CI, 1.21-1.40), elective cesarean section (aRR, 1.58; 95% CI, 1.45-1.71), and emergency cesarean section (aRR, 1.09; 95% CI, 1.00-1.20). Infants of mothers with epilepsy were at increased risks of stillbirth (aRR, 1.55; 95% CI, 1.05-2.30), having both medically indicated (aRR, 1.24; 95% CI, 1.08-1.43) and spontaneous (aRR, 1.34; 95% CI, 1.20-1.53) preterm birth, being small for gestational age at birth (aRR, 1.25; 95% CI, 1.13-1.30), and having neonatal infections (aRR, 1.42; 95% CI, 1.17-1.73), any congenital malformation (aRR, 1.48; 95% CI, 1.35-1.62), major malformations (aRR, 1.61; 95% CI, 1.43-1.81), asphyxia-related complications (aRR, 1.75; 95% CI, 1.26-2.42), Apgar score of 4 to 6 at 5 minutes (aRR, 1.34; 95% CI, 1.03-1.76), Apgar score of 0 to 3 at 5 minutes (aRR, 2.42; 95% CI, 1.62-3.61), neonatal hypoglycemia (aRR, 1.53; 95% CI, 1.34-1.75), and respiratory distress syndrome (aRR, 1.48; 95% CI, 1.30-1.68) compared with infants of unaffected women. In women with epilepsy, using AEDs during pregnancy did not increase the risks of pregnancy and perinatal complications, except for a higher rate of induction of labor (aRR, 1.30; 95% CI, 1.10-1.55).

Conclusions and Relevance

Epilepsy during pregnancy is associated with increased risks of adverse pregnancy and perinatal outcomes. However, AED use during pregnancy is generally not associated with adverse outcomes.

Risk of impaired cognition after prenatal exposure to psychotropic drugs

OBJECTIVE

Prenatal exposure to psychotropic drugs may affect the trajectories of brain development. In a register study, we investigated whether such exposure is associated with long-term impaired cognitive abilities.

METHOD

Individuals born in Denmark in 1995-2008 were included. As proxies for cognitive impairment, requiring special needs education, attending special needs school, diagnoses of neurological/mental disorder, missed final examinations, and low school grade average were used. We accounted for maternal confounders.

RESULTS

We identified 868 159 individuals of whom 13 983 (1.6%) were prenatally exposed. The adjusted odds ratio (OR) was 0.97[0.92-1.02] for requiring special needs education, 1.28[1.14-1.43] for attending special needs school, 1.32[1.20-1.46] for a neurological/mental disorder diagnosis, 1.37[1.22-1.54] for missing the final examinations, and 1.13[0.82-1.55] for obtaining a low school grade average. Exposure to psycholeptics (primarily antipsychotics and sedatives) was correlated with significantly increased risk for four outcomes. The highest was the risk of missing the primary school examinations (OR: 1.51[1.29-1.76]). The overall highest risk concerned the presence of a neurological/mental disorder after prenatal exposure to psychoanaleptics (primarily antidepressants) (OR: 1.86[1.24-2.78).

CONCLUSION

Prenatal exposure to psychotropic drugs affects proxy outcomes of cognitive disabilities at school age. Exposure to psycholeptics carries the largest risk. The role of psychoanaleptics is currently unclear.

The concordance between self-reported medication use and pharmacy records in pregnant women

PURPOSE

Several studies have been conducted to assess determinants affecting the performance or accuracy of self-reports. These studies are often not focused on pregnant women, or medical records were used as a data source where it is unclear if medications have been dispensed. Therefore, our objective was to evaluate the concordance between self-reported medication data and pharmacy records among pregnant women and its determinants.

METHODS

We conducted a population-based cohort study within the Generation R study, in 2637 pregnant women. The concordance between self-reported medication data and pharmacy records was calculated for different therapeutic classes using Yule's Y. We evaluated a number of variables as determinant of discordance between both sources through univariate and multivariate logistic regression analysis.

RESULTS

The concordance between self-reports and pharmacy records was moderate to good for medications used for chronic conditions, such as selective serotonin reuptake inhibitors or anti-asthmatic medications (0.88 and 0.68, respectively). Medications that are used occasionally, such as antibiotics, had a lower concordance (0.51). Women with a Turkish or other non-Western background were more likely to demonstrate discordance between pharmacy records and self-reported data compared with women with a Dutch background (Turkish: odds ratio, 1.63; 95% confidence interval, 1.16-2.29; other non-Western: odds ratio, 1.33; 95% confidence interval, 1.03-1.71).

CONCLUSIONS

Further research is needed to assess how the cultural or ethnic differences may affect the concordance or discordance between both medication sources. The results of this study showed that the use of multiple sources is needed to have a good estimation of the medication use during pregnancy.

Maternal asthma severity and control during pregnancy and risk of offspring asthma

BACKGROUND

Severe and uncontrolled asthma during pregnancy has been linked to several unfavorable perinatal outcomes. However, current knowledge on the association between the severity and control of maternal asthma and offspring asthma is sparse.

OBJECTIVE

We sought to investigate the extent to which offspring asthma is influenced by maternal asthma severity and control during pregnancy.

METHODS

We performed a prospective population-based cohort study. Using linkage of Danish national registers, we constructed a cohort of 675,379 singletons, of which 15,014 children were born to asthmatic mothers. Among them, 7,188 children were born to mothers with active asthma during pregnancy. We categorized mothers with active asthma into 4 groups based on dispensed antiasthma prescriptions and on use of medical services: mild controlled, mild uncontrolled, moderate-to-severe controlled, and moderate-to-severe uncontrolled asthma. The outcomes were offspring early-onset transient, early-onset persistent, and late-onset asthma. We estimated prevalence ratios (PRs) of each phenotype of asthma using a log-binomial model with 95% CIs.

RESULTS

Higher prevalence of early-onset persistent asthma was observed among children of asthmatic mothers with mild uncontrolled (PR, 1.19; 95% CI, 1.05-1.35), moderate-to-severe controlled (PR, 1.33; 95% CI, 1.09-1.63), and moderate-to-severe uncontrolled asthma (PR, 1.37; 95% CI, 1.17-1.61) compared with those of mothers with mild controlled asthma. A borderline increased prevalence of early-onset transient asthma was observed among children of mothers with uncontrolled asthma.

CONCLUSION

Maternal uncontrolled asthma increases the risk of early-onset persistent and transient asthma. If replicated, this could suggest that maintaining asthma control in pregnancy is an area for possible prevention of specific phenotypes of offspring asthma.

Maternal use of selective serotonin reuptake inhibitors during pregnancy is associated with Hirschsprung's disease in newborns - a nationwide cohort study

BACKGROUND

Hirschsprung's disease is a rare condition caused by congenital malformation of the gastrointestinal tract affecting 1:5000 children. Not much is known about risk factors for development of Hirschsprung's disease. Two clinical cases of hirschsprung's disease led to an investigation of the association between maternal use of selective serotonin reuptake inhibitors (SSRIs) during pregnancy and development of Hirschsprung's Disease in the newborn child. The study examined a nationwide, unselected cohort of children born in Denmark from 1 January 1996 until 12 March 2016 (n = 1,256,317). We applied multivariate models to register-based data to estimate the odds ratio of Hirschsprung's disease, adjusting for possible confounders. The studied exposure period for SSRIs were 30 days prior to conception to the end of the first trimester.

RESULTS

In the main exposed cohort the prevalence of Hirschsprung's disease was 16/19.807 (0.08%) compared to 584/1.236.510 (0.05%) in the unexposed cohort. In women who redeemed a minimum of one prescription of selective serotonin reuptake inhibitors, the adjusted odds ratio for development of Hirschsprung's disease was 1.76 (95%CI: 1.07-2.92). In women who redeemed a minimum of two prescriptions, the adjusted odds ratio for Hirschsprung's disease was 2.34 (95% CI: 1.21-4.55).

CONCLUSIONS

Our data suggest that early maternal use of selective serotonin reuptake inhibitors is significantly associated with the development of Hirschsprung's disease in the newborn child. Treatment of depression during pregnancy always has to be weighed against the risks posed by untreated maternal depression. Our results have to be confirmed in other studies.

Selective serotonin reuptake inhibitors and risk of major congenital anomalies for pregnancies in Japan: A nationwide birth cohort study of the Japan Environment and Children's Study

We analyzed data from the Japan Environment and Children's Study (JECS), on the association between selective serotonin reuptake inhibitors (SSRI) use during pregnancy and the risk of developing of major congenital anomalies in Japan. JECS is an ongoing nationwide birth cohort study. The study includes 95 994 single pregnant women and their offspring. Among them, 172 used any SSRI up to the 12^th gestational week. Crude analyses show a significantly increased incidence of upper limb, abdominal, and urogenital abnormalities. In particular, the incidence of microcephaly, hydrencephalus, esophageal atresia, small intestinal atresia, and achondroplasia was significantly higher with than without exposure to these substances. On multivariate analyses, urogenital abnormality was significant (odds ratio 3.227; 95% confidence interval: 1.460-7.134). This Japanese nationwide birth cohort survey clarified that the use of any SSRI until the 12^th gestational week was associated with urogenital abnormality in children. The survey for association with minor classification abnormality needs further examination in Japan.

Administrative Claims Data Versus Augmented Pregnancy Data for the Study of Pharmaceutical Treatments in Pregnancy

Purpose of Review

Administrative claims databases, which collect reimbursement-related information generated from healthcare encounters, are increasingly used to evaluate medication safety in pregnancy. We reviewed the strengths and limitations of claims-only databases and how other data sources may be used to improve the accuracy and completeness of information critical for studying medication safety in pregnancy.

Recent Findings

Research on medication safety in pregnancy requires information on pregnancy episodes, mother-infant linkage, medication exposure, gestational age, maternal and birth outcomes, confounding factors, and (in some studies) long-term follow-up data. Claims data reliably identifies live births and possibly other pregnancies. It allows mother-infant linkage and has prospectively collected prescription medication information. Its diagnosis and procedure information allows estimation of gestational age. It captures maternal medical conditions but generally has incomplete data on reproductive and lifestyle factors. It has information on certain, typically short-term maternal and infant outcomes that may require chart review confirmation. Other data sources including electronic health records and birth registries can augment claims data or be analyzed alone. Interviews, surveys, or biological samples provide additional information. Nationwide and regional birth and pregnancy registries, such as those in several European and North American countries, generally contain more complete information essential for pregnancy research compared to claims-only databases.

Summary

Claims data offers several advantages in medication safety in pregnancy research. Its limitations can be partially addressed by linking it with other data sources or supplementing with primary data collection. Rigorous assessment of data quality and completeness is recommended regardless of data sources.

Can We Rely on Pharmacy Claims Databases to Ascertain Maternal Use of Medications during Pregnancy?

BACKGROUND

Administrative databases are increasingly used to measure drug exposure in perinatal pharmacoepidemiology. We aimed to estimate the concordance between records of prescriptions filled in pharmacies and self-reported drug use during pregnancy.

METHODS

Data on self-reported medication use were collected at each trimester of pregnancy among a sub-sample from the Organization of Teratology Information Specialists Antidepressants in Pregnancy Cohort. Women were eligible if they were Quebec resident and provided their pharmacist's contact information. Maternal self-reports were compared with prescriptions filled in pharmacies, which are transferred to pharmaceutical services files of Quebec provincial health plan database (Régie de l'asssurance maladie du Québec). Positive and negative predictive values (PPV and NPV) for medications taken chronically (antidepressants, thyroid hormones), acutely (antibiotics), and as needed (antiemetics, asthma medications) were calculated.

RESULTS

Among the 93 participants (mean age = 30.2 ± 3.8 years), 41.9% (n = 39) took at least one antidepressant during pregnancy according to self-reports, and 39.8% (n = 37) according to pharmacy records. Other commonly used drugs were antiemetics (self-reported 22.6%, pharmacy record 24.7%), antibiotics (20.4%, 16.1%), asthma medications (15.1%, 15.1%), and thyroid hormones (10.8%, 8.6%). PPVs and NPVs were: (1) chronic medication: antidepressants PPV = 100% (95% confidence interval [CI], 100-100%), NPV = 96% (95% CI, 92-100%); thyroid hormones PPV = 100% (95% CI, 100-100%), NPV = 98% (95% CI, 95-100%); (2) Acute medication: antibiotics PPV = 87% (95% CI, 70-100%), NPV = 92% (95% CI, 86-98%); (3) as needed medications: antiemetics: PPV = 78% (95% CI, 62-95%), NPV = 96% (95% CI, 91-100%); asthma: PPV = 33% (95% CI, 3-64%), NPV = 99% (95% CI, 97-100%).

CONCLUSION

The high PPV and NPV validate the use of filled prescription data in large databases as a measure of medication exposure. Birth Defects Research 109:423-431, 2017. © 2017 Wiley Periodicals, Inc.

Prenatal exposure to antiepileptic drugs and use of primary healthcare during childhood: a population-based cohort study in Denmark

OBJECTIVE

Prenatal exposure to antiepileptic drugs (AEDs) has been associated with adverse outcomes in the offspring such as congenital malformations and neuropsychiatric disorders. The objective of this study was to investigate whether prenatal exposure to AEDs is also associated with more frequent use of primary healthcare during childhood.

DESIGN

Population-based cohort study.

SETTING

Nationwide national registers in Denmark.

PARTICIPANTS

All live-born singletons in Denmark during 1997-2012 identified in the Danish National Patient Register and followed until 31 December 2013 (n=963 010). Information on prenatal exposure to AEDs for maternal indication of epilepsy and other neurological conditions was obtained from the Danish Register of Medicinal Product Statistics.

MAIN OUTCOME MEASURES

The primary outcome measure was the number and type of contacts with the general practitioner (GP), excluding routine well-child visits and vaccinations. The secondary outcome measure was specific services provided at the GP contact. The association between prenatal exposure to AEDs and contacts with the GP was estimated by using negative binomial regression adjusting for sex and date of birth of the child, maternal age, cohabitation status, income, education, substance abuse, depression, severe psychiatric disorders and use of antipsychotics, antidepressants and insulin.

RESULTS

Children exposed prenatally to AEDs (n=4478) had 3% (95% CI 0 to 5%) more GP contacts during the study period than unexposed children. This was primarily accounted for by the number of phone contacts. Within each year of follow-up, exposed children tended to have more contacts than unexposed children, but the differences were small. We found no difference between exposed and unexposed children with regard to specific services provided at the GP contact. For the individual AEDs, we found that exposure to valproate or oxcarbazepine was associated with more GP contacts.

CONCLUSIONS

We found only minor differences between prenatally AED-exposed and unexposed children in the number of GP contacts.

Validation of maternal recall of early pregnancy medication exposure using prospective diary data

PURPOSE

Data about maternal recall accuracy for classifying early pregnancy medication exposure are meager. Nonetheless, studies often rely on recall to evaluate potential impact of pharmaceuticals on the developing fetus.

METHODS

Right from the Start is a community-based pregnancy cohort that enrolled women from North Carolina, Tennessee, and Texas. A subset of 318 women participated in daily medication diaries initiated before conception (2006-2012). We examined nonsteroidal anti-inflammatory drugs (NSAIDs) as an example of a drug type that is difficult to study due to its intermittent and primarily over-the-counter use as well as its incomplete documentation in medical and pharmaceutical records. Selective serotonin reuptake inhibitors (SSRI) were assessed as a prescription medication comparator. Maternal recall of NSAID and SSRI use in early pregnancy was examined by comparing diary data (gold standard) to first-trimester interview.

RESULTS

Sensitivity and specificity for recall of NSAID exposure were 78.6% and 62.3%, respectively (kappa statistic: 0.41), with 72.3% agreement for exposure classification. Sensitivity and specificity for recall of SSRI exposure were 77.8% and 99.0%, respectively (kappa statistic: 0.79), with 97.8% agreement.

CONCLUSIONS

Our findings suggest the validity of maternal recall varies with medication type and prospective data collection should be prioritized when studying early pregnancy drug exposures.

Risk Factors of Early Otitis Media in the Danish National Birth Cohort

OBJECTIVE

To assess risk factors of otitis media (OM) in six-months-old children.

METHOD

The sample consisted of 69,105 mothers and their children from the Danish National Birth Cohort. The women were interviewed twice during pregnancy and again 6 months after birth. The outcome "one or more" maternal reported episodes of OM at age six months. In total 37 factors were assessed, covering prenatal, maternal, perinatal and postnatal factors.

RESULTS

At age six months 5.3% (95% CI 5.1-5.5) of the children had experienced one or more episodes of OM. From the regression analysis, 11 variables were associated with a risk of OM. When a Bonferroni correction was introduced, gender, prematurity, parity, maternal age, maternal self-estimated health, taking penicillin during pregnancy, and terminating breastfeeding before age six months, was associated with a risk of early OM. The adjusted ORs of OM for boys versus girls was 1.30 (95% CI 1.18-1.44). The OR having one sibling versus no siblings was 3.0 (95% CI 2.64-3.41). If the woman had been taking penicillin during pregnancy, the OR was 1.35 (95% CI 1.15-1.58). Children born before 38th gestational week had an increased OR for early OM of 1.49 (95% CI 1.21-1.82). Children of young women had an increased OR of early OM compared to children of older women. Additionally, children of women who rated their own health low compared to those rating their health as high, had an increased OR of 1.38 (95% CI 1.10-1.74). Finally, children being breastfeed less than 6 months, had an increased OR of 1.42 (95% CI 1.28-1.58) compared to children being breastfeed beyond 6 months.

CONCLUSION

These findings indicate that prenatal factors are of less importance regarding early OM before the age of six months. Postnatal risk factors seem to pose the main risk of early OM.

Medication adherence in women with epilepsy who are planning pregnancy

OBJECTIVE

This study examines medication adherence among women with epilepsy via use of an electronic diary, as part of a prospective multicenter observational study designed to evaluate fertility in women with epilepsy (WWE) versus age-matched controls.

METHODS

WWE and healthy age-matched controls, seeking pregnancy, were given an iPod Touch using a customized mobile application (the WEPOD App) for daily data tracking. Eighty-six WWE tracked seizures and antiepileptic drugs (AEDs). Tracking of nonepilepsy medications was optional. Diary data were counted from enrollment date until date of delivery, or up to 12 months if pregnancy was not achieved. Each day that subjects reported missing one or more AED was counted as nonadherence. Because adherence can only be determined in women who track consistently, we elected to include adherence data only for women who tracked >80% of days in the study.

RESULTS

Approximately 75% of WWE tracked >80% of days and were included in medication adherence data analysis. In this group, medication adherence rate was 97.71%; 44% of women admitted to missing an AED on at least 1 day. Among the subgroup of WWE who recorded nonepilepsy medications, AED adherence rate was 98.56%, versus 93.91% for non-AEDs.

SIGNIFICANCE

The 75% compliance rate with an electronic diary suggests that it may be useful to track medication adherence in future studies and in the clinical setting. In those who tracked, the observed medication adherence rate was considerably higher than the 75% adherence rate seen in previous epilepsy studies. This might be explained in part by selection bias, but may also result from properties of the diary itself (daily reminders, real time feedback given to the provider). Women reported a higher rate of adherence to AEDs than to other prescribed medications and supplements, suggesting that perceived importance of medications likely influences medication adherence, and warrants future study.

Prenatal exposure to antidepressants and risk of epilepsy in childhood

PURPOSE

This study aimed to estimate the association between prenatal exposure to antidepressants and risk of epilepsy in childhood, taking maternal depression into account.

METHODS

We conducted a population-based cohort study including all Danish singletons born alive between 1997 and 2008 (n = 734 237). Information on antidepressant medication and diagnosis of depression and epilepsy was obtained from Danish National Registers. The exposed group comprised children of mothers who used antidepressants from 30 days before pregnancy until the date of birth. The reference group comprised children of mothers who used no antidepressants from 6 months before pregnancy to birth. We estimated the hazard ratios (HR) of epilepsy and 95% confidence intervals (CI) using Cox proportional hazard models.

RESULTS

We identified 12 438 (1.7%) children exposed to antidepressants during pregnancy (including 30 days before pregnancy) and 5829 (0.8%) children diagnosed with epilepsy in the follow-up time (mean: 6.7 years). Children exposed to antidepressants during pregnancy had a 27% higher risk of epilepsy (aHR: 1.27; 95%CI: 1.05-1.54) than children in the reference group. The estimate of this association was 1.71 (95%CI: 1.10-2.66) if their mothers also had a registry-based hospital diagnosis of depression in the 6 months before pregnancy or during pregnancy and 1.14 (95%CI: 0.91-1.43) if their mothers had no registry-based hospital diagnosis of depression. Children of mothers who used antidepressants from 2 to 6 months before pregnancy (but not during pregnancy) had an increased risk of epilepsy (aHR: 1.36; 95%CI: 1.07-1.73).

CONCLUSIONS

Antidepressant use during pregnancy was associated with a higher risk of epilepsy among children whose mothers had also a registry-based hospital diagnosis of depression during pregnancy. Copyright © 2016 John Wiley & Sons, Ltd.

Actual Use of Medications Prescribed During Pregnancy: A Cross-Sectional Study Using Data from a Population-Based Congenital Anomaly Registry

Introduction and Aim

Data from prescription databases are increasingly being used to study associations between maternal medications used in pregnancy and congenital anomalies. We therefore investigated the extent to which prescriptions reflect the actual use of medication during pregnancy, and whether medicines used during pregnancy are taken according to the prescribed dosage and duration.

Methods

We performed a cross-sectional study in a population-based congenital anomaly register (EUROCAT Northern Netherlands). We included 202 women who had at least one prescription during their pregnancy and who gave birth between 2009 and 2011. Compliance with the prescribed medication was verified by telephone interview. We calculated the compliance rates for several medication groups by dividing the number of mothers who confirmed they had taken the medication by the total number to whom it had been prescribed. Compliance was positive if the mother confirmed she took the medication, even if she only took one of several prescriptions from the same medication group. For each prescription taken, we also determined whether her use conformed to the prescribed dosage and duration.

Results

During the first trimester, the compliance rates ranged from 0.84 (for chronic diseases) to 0.92 (for pregnancy-related symptoms). Most of the medications actually taken were used at the prescribed dosage or lower. More than half of the medications actually taken were used for the duration prescribed or shorter.

Conclusion

Prescription records are generally a relatively reliable source of data for research into associations between medication use in pregnancy and congenital anomalies compared with other data sources. Pharmacy records of medication use in pregnancy might represent an overestimation, which should be taken into account. However, our results show that, except for ‘corticosteroids, dermatological preparations’; ‘ear, eye, nose and throat preparations’; and ‘anxiolytics, hypnotics and sedatives’, this overestimation generally seems minimal.

Electronic supplementary material

The online version of this article (doi:10.1007/s40264-015-0302-z) contains supplementary material, which is available to authorized users.

Prevalence of prescription medication use among non-pregnant women of childbearing age and pregnant women in the United States: NHANES, 1999-2006

Many prescription medications have limited information regarding safety for use during pregnancy. In order to inform research on safer medication use during pregnancy, we examined prescription medication use among women in the United States. We analyzed data from the 1999-2006 National Health and Nutrition Examination Survey (NHANES) to estimate the prevalence of prescription medication use in the past 30 days among pregnant women and non-pregnant women of childbearing age (15-44 years) and to ascertain the most commonly reported prescription medications by women in these groups. We assessed how the most commonly reported medications differed among groups defined by selected demographic characteristics, including age, race/ethnicity, and markers of socioeconomic status. Prescription medication use in the past 30 days was reported by 22 % of pregnant women and 47 % of non-pregnant women of childbearing age. The most commonly reported prescription medications by NHANES participants differed somewhat by pregnancy status; allergy and anti-infective medications were more common among pregnant women, while oral contraceptives were more common among non-pregnant women. Use of prescription medication for asthma and thyroid disorders was reported by both groups. Although prescription medication use in the previous 30 days was less common among pregnant women than non-pregnant women, its use was reported among almost 1 in 4 pregnant women. Many of the most common medications reported were for the treatment of chronic medical conditions. Given the potential impact of medications on the developing fetus, our data underscore the importance of understanding the safety of these medications during pregnancy.

Association of prenatal exposure to acetaminophen and coffee with childhood asthma

PURPOSE

Some studies have suggested that maternal acetaminophen use during pregnancy is associated with asthma in the offspring, and coffee consumption may modify the toxicity of acetaminophen. We aim to examine whether pregnancy maternal acetaminophen use increases the risk for offspring asthma, and whether such a potential association could be modified by maternal coffee consumption.

METHODS

We included 63,652 live-born singletons enrolled in the Danish National Birth Cohort. Maternal acetaminophen use and coffee consumption during pregnancy were assessed prospectively via the enrolment questionnaire and three computer-assisted telephone interviews. Asthma cases were identified by using the Danish National Patient Register and the Danish National Prescription Registry. We estimated the hazard ratios (HRs) for asthma according to prenatal acetaminophen and coffee exposure using Cox proportional hazards regression model.

RESULTS

After adjusting for potential confounders, acetaminophen use during pregnancy was associated with an increased risk of offspring asthma (HR = 1.16, 95% confidence interval (CI): 1.11-1.22). Coffee drinking during pregnancy was associated with a slightly decreased risk (HR = 0.94, 95%CI: 0.90-0.99). But there was no strong evidence of effect measure modification of acetaminophen use on offspring asthma by coffee consumption.

CONCLUSIONS

Acetaminophen use during pregnancy was associated with a modest increased risk for offspring asthma, which was not modified by coffee consumption.

Medication use during pregnancy, gestational age and date of delivery: agreement between maternal self-reports and health database information in a cohort

Background

Health databases are a promising resource for epidemiological studies on medications safety during pregnancy. The reliability of information on medications exposure and pregnancy timing is a key methodological issue. This study (a) compared maternal self-reports and database information on medication use, gestational age, date of delivery; (b) quantified the degree of agreement between sources; (c) assessed predictors of agreement.

Methods

Pregnant women recruited in a prenatal clinic in Friuli Venezia Giulia (FVG) region, Italy, from 2007 to 2009, completed a questionnaire inquiring on medication use during pregnancy, gestational age and date of delivery. Redeemed prescriptions and birth certificate records were extracted from regional databases through record linkage. Percent agreement, Kappa coefficient, prevalence and bias-adjusted Kappa (PABAK) were calculated. Odds Ratio (OR), with 95 % confidence interval (95 % CI), of ≥1 agreement was calculated through unconditional logistic regression.

Results

The cohort included 767 women, 39.8 % reported medication use, and 70.5 % were dispensed at least one medication. Kappa and PABAK indicated almost perfect to substantial agreement for antihypertensive medications (Kappa 0.86, PABAK 0.99), thyroid hormones (0.88, 0.98), antiepileptic medications (1.00, 1.00), antithrombotic agents (0.70, 0.96). PABAK value was greater than Kappa for medications such as insulin (Kappa 0.50, PABAK 0.99), antihistamines for systemic use (0.50, 0.99), progestogens (0.28, 0.79), and antibiotics (0.12, 0.63). Adjusted OR was 0.48 (95 % CI 0.26; 0.90) in ex- vs. never smokers, 0.64 (0.38; 1.08) in < high school vs. university, 1.55 (1.01; 2.37) in women with comorbidities, 2.25 (1.19; 4.26) in those aged 40+ vs. 30–34 years.

Gestational age matched exactly in 85.2 % and date of delivery in 99.5 %.

Conclusions

For selected medications used for chronic conditions, the agreement between self-reports and dispensing data was high. For medications with low to very low prevalence of use, PABAK provides a more reliable measure of agreement. Maternal reports and dispensing data are complementary to each other to increase the reliability of information on the use of medications during pregnancy. Birth certificates provide reliable data on the timing of pregnancy. FVG health databases are a valuable source of data for pregnancy research.

Electronic supplementary material

The online version of this article (doi:10.1186/s12884-015-0745-3) contains supplementary material, which is available to authorized users.

Healthcare utilisation by pregnant patients with asthma in South Korea: a cohort study using nationwide claims data

OBJECTIVES

Few nationwide population-based studies have examined the burden of asthma during pregnancy. Here, we investigated the burden and medical treatment of asthma during pregnancy requiring healthcare utilisation in South Korea.

DESIGN

Cohort study.

SETTING

Nationwide insurance claims database.

PARTICIPANTS

A total of 1,306,281 pregnant women who delivered in South Korea in 2009-2011.

OUTCOMES

The prevalence and exacerbation rates of asthma requiring healthcare utilisation, and the prescription of antiasthmatic drugs during pregnancy.

RESULTS

The prevalence of asthma requiring healthcare utilisation was 0.43% among pregnant women. Among those with asthma requiring healthcare utilisation, 6.9% were hospitalised and treated with systemic steroids and short-acting β2-agonists during pregnancy. Oral drugs were prescribed less during the third trimester than during the first trimester (all p values for trends were <0.001). A significant number of patients with asthma were likely to stop taking antiasthmatic drugs after becoming pregnant.

CONCLUSIONS

The prevalence of asthma requiring healthcare utilisation during pregnancy was not very high. However, a significant number of women were likely to stop taking antiasthmatic drugs, and those who did tended to experience exacerbations.

Apgar-score in children prenatally exposed to antiepileptic drugs: a population-based cohort study

OBJECTIVES

It is unknown if prenatal exposure to antiepileptic drugs (AEDs) increases the risk of low Apgar score in offspring.

SETTING

Population-based study using health registers in Denmark.

PARTICIPANTS

We identified all 677 021 singletons born in Denmark from 1997 to 2008 and linked the Apgar score from the Medical Birth Register with information on the women's prescriptions for AEDs during pregnancy from the Danish Register of Medicinal Product Statistics. We used the Danish National Hospital Registry to identify mothers diagnosed with epilepsy before birth of the child. Results were adjusted for smoking and maternal age.

RESULTS

Among 2906 children exposed to AEDs, 55 (1.9%) were born with an Apgar score ≤7 as compared with 8797 (1.3%) children among 674 115 pregnancies unexposed to AEDs (adjusted relative risk (aRR)=1.41 (95% CI 1.07 to 1.85). When analyses were restricted to the 2215 children born of mothers with epilepsy, the aRR of having a low Apgar score associated with AED exposure was 1.34 (95% CI 0.90 to 2.01) When assessing individual AEDs, we found increased, unadjusted RR for exposure to carbamazepine (RR=1.86 (95% CI 1.01 to 3.42)), valproic acid (RR=1.85 (95% CI 1.04 to 3.30)) and topiramate (RR=2.97 (95% CI 1.26 to 7.01)) when compared to unexposed children.

CONCLUSIONS

Prenatal exposure to AEDs was associated with increased risk of being born with a low Apgar score, but the absolute risk of a low Apgar score was <2%. Risk associated with individual AEDs indicate that the increased risk is not a class effect, but that there may be particularly high risks of a low Apgar score associated with certain AEDs.

Risk of Fetal Death after Treatment with Antipsychotic Medications during Pregnancy

Background

Antipsychotic medications are increasingly used during pregnancy. Nevertheless, fetal risks are still not fully studied. It is currently unclear whether the antipsychotic treatment might induce a higher risk of fetal death. We aimed to determine if use of antipsychotic medication during pregnancy is associated with an increased risk of spontaneous abortion or stillbirth.

Methods

In a historical cohort study, we identified all clinically recognized pregnancies registered in the nationwide Danish registries from 1997 to 2008 (N = 1,005,319). Exposure was defined as any prescription of antipsychotic medications redeemed by the pregnant women during the exposure window, and recorded in the Danish National Prescription Register. Outcome was defined as any spontaneous abortion or stillbirth recorded in the Danish National Hospital Register and the Danish Medical Birth Register respectively.

Results

Women exposed to antipsychotic medications during pregnancy had a 34% higher risk of spontaneous abortion (adjusted relative risk = 1.34; 95% confidence interval = 1.22; 1.46) compared to unexposed women, but a similar risk compared to women exposed prior to (but not during) pregnancy (adjusted relative risk = 1.04; 95% confidence interval = 0.93; 1.17). The risk of spontaneous abortion was not increased in exposed pregnancies when compared to unexposed pregnancies in the same women (adjusted hazard ratio = 1.11; 95% CI = 0.94; 1.31). A twofold higher risk of stillbirth was found in women exposed to antipsychotic medications compared with unexposed women (relative risk = 2.27; 95% confidence interval = 1.45; 3.55) and compared with women exposed only prior to pregnancy (relative risk = 2.06; 95% confidence interval = 1.01; 4.19).

Conclusions

The increased risk of spontaneous abortion found in women treated with antipsychotic medications during pregnancy is most likely due to confounding factors. The risk of stillbirth was twofold higher in pregnancies exposed to antipsychotic medication during pregnancy. Treatment with antipsychotic medications during pregnancy requires careful consideration.

Depression, Anxiety, and Pharmacotherapy Around the Time of Pregnancy in Hawaii

BACKGROUND

Depression and anxiety are common conditions among pregnant and postpartum women, but population-based information is lacking on treatments and help-seeking behaviors.

PURPOSE

This study described the prevalence of depression, anxiety, pharmaceutical treatment, and help-seeking behaviors among a multiethnic population of women with recent live births in Hawaii.

METHOD

Hawaii Pregnancy Risk Assessment Monitoring System data from 4735 respondents were weighted to be representative of all pregnancies resulting in live births in Hawaii in 2009-2011 and were used to estimate the prevalence of several indicators related to anxiety and depression before, during, and after pregnancy among women with recent live births.

RESULTS

Of Hawaii women with live births in 2009-2011, 7.3 % reported visiting a healthcare worker to be checked or treated for depression or anxiety in the year before their most recent pregnancy, 4.9 % reported having depression in the 3 months before pregnancy, 5.9 % reported having anxiety in the same period, 9.1 % screened positive for postpartum depression, and 6.9 % reported asking a doctor, nurse, or other healthcare worker for help for anxiety postpartum. The prevalence of antianxiety and antidepressant prescription drug use was 2.3 % in the month before pregnancy and 1.4 % during pregnancy. Hawaii had lower prevalence of pre-pregnancy depression, anxiety, and depression/anxiety health visits than other US states. Pre-pregnancy depression and anxiety and postpartum anxiety help-seeking behaviors differed significantly by race/ethnicity.

CONCLUSION

Depression and anxiety are common among pregnant and postpartum women in Hawaii. More research could better inform heath care professionals and patients of the treatment options available and their potential risks and benefits.

Selective serotonin reuptake inhibitors and venlafaxine in early pregnancy and risk of birth defects: population based cohort study and sibling design

OBJECTIVE

To assess whether use of specific selective serotonin reuptake inhibitors (SSRIs) or venlafaxine in early pregnancy is associated with an increased risk of birth defects, with emphasis on cardiovascular birth defects even when accounting for lifestyle or other familial confounding.

DESIGN

Multicountry population based cohort study, including sibling controlled design.

SETTING

Nordic population (Denmark, Finland, Iceland, Norway, and Sweden) identified from nationwide health registers at different periods in 1996-2010.

POPULATION

The full study cohort included women giving birth to 2.3 million live singletons. The sibling cohort included 2288 singleton live births. The sibling controlled analyses included sibling pairs who were discordant for exposure to SSRIs or venlafaxine and birth defects.

MAIN OUTCOME MEASURE

Prevalence of birth defects, including subtypes of cardiac defects. Odds ratio of birth defects from logistic and conditional logistic regression.

RESULTS

Among 36,772 infants exposed to any SSRI in early pregnancy, 3.7% (n=1357) had a birth defect compared with 3.1% of 2,266,875 unexposed infants, yielding a covariate adjusted odds ratio of 1.13 (95% confidence interval 1.06 to 1.20). In the sibling controlled analysis the adjusted odds ratio decreased to 1.06 (0.91 to 1.24). The odds ratios for any cardiac birth defect with use of any SSRI or venlafaxine were 1.15 (95% confidence interval 1.05 to 1.26) in the covariate adjusted analysis and 0.92 (0.72 to 1.17) in the sibling controlled analysis. For atrial and ventricular septal defects the covariate adjusted odds ratio was 1.17 (1.05 to 1.31). Exposure to any SSRI or venlafaxine increased the prevalence of right ventricular outflow tract obstruction defects, with a covariate adjusted odds ratio of 1.48 (1.15 to 1.89). In the sibling controlled analysis the adjusted odds ratio decreased to 0.56 (0.21 to 1.49) for any exposure to SSRIs or venlafaxine and right ventricular outflow tract obstruction defects.

CONCLUSIONS

In this large Nordic study no substantial increase was found in prevalence of overall cardiac birth defects among infants exposed to SSRIs or venlafaxine in utero. Although the prevalence of septal defects and right ventricular outflow tract defects was higher in exposed infants, the lack of an association in the sibling controlled analyses points against a teratogenic effect of these drugs.

Prevalence of prescribing in pregnancy using the Irish primary care research network: a pilot study

Background

To establish the prevalence and patterns of prescribing to pregnant women in an Irish primary care setting.

Methods

We reviewed electronic healthcare records routinely collected in primary care, of pregnant women attending nine Dublin-based General Practices affiliated to the Irish Primary Care Research Network (IPCRN) for antenatal care between January 2007 and October 2013 (n = 2,361 pregnancies).

Results

Excluding folic acid, 46.8% (n = 1,104) of pregnant women were prescribed at least one medication. Amoxicillin (11.1%, n = 263) and co-amoxiclav (8.0%, n = 190) were the most commonly prescribed medication followed by topical clotrimazole (4.9%, n = 117), salbutamol inhalers (4.1%, n = 96) and paracetamol (4.0%, n = 95). General Medical Services (GMS) patients were more likely to receive a prescription than private patients (OR 2.81; 95%CI (2.28, 3.47)). We applied the US FDA pregnancy-risk categories as a proxy measure of prescribing appropriateness, with FDA Category D and X medications considered inappropriate. FDA Category D drugs were prescribed in 5.9% (n = 140) of pregnancies. FDA Category X drugs were prescribed in 4.9% (n = 116) of pregnancies but after exclusion of oral contraceptives, progestogens, infertility treatments Category X medications were prescribed in 0.6% (n = 13) of pregnancies. After the initial antenatal consultation the prescribing prevalence of FDA Category D medications reduced to 4.7% (n = 110) and Category X to 3.1% (n = 72).

Conclusions

The overall prevalence of prescribing to pregnant women in our cohort is low compared to studies internationally, however similar levels of prescribing for FDA Category D and X were found. Following the initial antenatal consultation levels of prescribing of the FDA Category D and X medications reduced, however there is potential to further reduce their use in early pregnancy. The IPCRN database has provided valuable information on the current practice of antenatal prescribing within this pilot group of practices however it is limited by the absence of morbidity and pregnancy outcome data.

Challenges in Studying Modifiable Risk Factors for Birth Defects

Conducting research to identify modifiable risk factors for birth defects is difficult for a variety of reasons. While some challenges are familiar to researchers across many disciplines, the confluence of issues affecting birth defects research may not be well understood by those outside of the field. This article describes several methodological challenges to the study of birth defects and ways these challenges might be addressed: (1) ascertainment, definition and classification of birth defects; (2) exposure assessment on modifiable risk factors; (3) analytical challenges related to small numbers and multiple statistical tests; (4) the role of genetics, including the collection of specimens and analysis of genetic data; and (5) challenges in translating research and demonstrating public health impact. Understanding these issues is important for researchers planning studies, reviewers evaluating the scientific merit of results from these studies, and consumers of the research, including fellow researchers, policy makers, health care providers, and families.

Ethics of studies of drugs in pregnancy

Pregnant women with illness require efficacious and safe drug therapy during pregnancy; however, their treatment is often hindered by a lack of information regarding the use of medications during pregnancy. Ethical challenges are encountered in conducting drug trials in pregnant women, who are often excluded from participation due to fear of harm to the fetus. However, as the health of the fetus is ultimately affected by that of the pregnant woman, inclusion of pregnant women in studies of medications that they may require for their own benefit may also benefit the unborn child. The principle of autonomy argues for the pregnant woman being able to make an informed choice to take part in a clinical trial, and the principle of justice dictates that she not be denied the benefits of drug research.

Adverse pregnancy outcomes after exposure to methylphenidate or atomoxetine during pregnancy

OBJECTIVE

To determine if prenatal exposure to methylphenidate (MPH) or atomoxetine (ATX) increases the risk of adverse pregnancy outcomes in women with attention deficit/hyperactivity disorder (ADHD).

MATERIALS AND METHODS

This was a population-based cohort study of all pregnancies in Denmark from 1997 to 2008. Information on use of ADHD medication, ADHD diagnosis, and pregnancy outcomes was obtained from nationwide registers.

RESULTS

We identified 989,932 pregnancies, in which 186 (0.02%) women used MPH/ATX and 275 (0.03%) women had been diagnosed with ADHD but who did not take MPH/ATX. Our reference pregnancies had no exposure to MPH/ATX and no ADHD diagnosis. Exposure to MPH/ATX was associated with an increased risk of spontaneous abortion (SA; ie, death of an embryo or fetus in the first 22 weeks of gestation) (adjusted relative risk [aRR] 1.55, 95% confidence interval [CI] 1.03-2.36). The risk of SA was also increased in pregnancies where the mother had ADHD but did not use MPH/ATX (aRR 1.56, 95% CI 1.11-2.20). The aRR of Apgar scores <10 was increased among exposed women (aRR 2.06, 95% CI 1.11-3.82) but not among unexposed women with ADHD (aRR 0.99, 95% CI 0.48-2.05).

CONCLUSION

MPH/ATX was associated with a higher risk of SA, but our study indicated that it may at least partly be explained by confounding by indication. Treatment with MPH/ATX was however associated with low Apgar scores <10, an association not found among women with ADHD who did not use MPH/ATX.

Considerations in using registry and health plan data for studying pregnancy in rheumatic diseases

PURPOSE OF REVIEW

The purpose of this review is to critically evaluate the strengths and limitations of different data sources for pregnancy-related research in patients with rheumatic diseases. We describe challenges in studying adverse pregnancy outcomes in the setting of observational research, with a particular focus on the studies of maternal drug exposures.

RECENT FINDINGS

We discuss potential threats to validity in the assessment of exposure and outcomes and controlling for confounding; present findings from selected pregnancy-related observational studies conducted using data from registries and health plans; and highlight future research opportunities for pregnancy research.

SUMMARY

Registry and health plan data contribute complementary information to each other. Used together, linked data sources may allow clinicians, researchers, and patients to obtain a more complete understanding of the risk and benefits associated with maternal drug exposure and of the risk factors associated with adverse birth outcomes in women with rheumatic disease.

Use of antidepressants and association with elective termination of pregnancy: population based case-control study

OBJECTIVE

To assess whether the use of selective serotonin reuptake inhibitors (SSRIs), tricyclic antidepressants, mirtazapine, venlafaxine or other antidepressants is associated with late elective termination of pregnancy.

DESIGN

Case-control study using data from national registers.

SETTING

Denmark, Finland, and Norway during the period 1996-2007.

POPULATION

A total of 14,902 women were included as cases and 148,929 women were included as controls.

METHODS

Cases were women with elective termination of pregnancy at 12-23 weeks of gestation. Controls continued their pregnancy and were matched with cases on key factors.

MAIN OUTCOME MEASURES

Association between antidepressant use during pregnancy and elective termination of pregnancy at 12-23 weeks of gestation for fetal anomalies, or for maternal ill health or socio-economic disadvantage.

RESULTS

At least one prescription of antidepressants was filled by 3.7% of the cases and 2.2% of the controls. Use of any type of antidepressant was associated with elective termination of pregnancy for maternal ill health or socio-economic disadvantage (odds ratio, OR 2.3; 95% confidence interval, 95% CI 2.0-2.5). Elective termination of pregnancy for fetal anomalies was associated with the use of mirtazapine (OR 2.2, 95% CI 1.1-4.5). There was no association between the use of any of the other antidepressants and elective termination of pregnancy for fetal anomalies.

CONCLUSION

The use of any type of antidepressants was associated with elective termination of pregnancy at 12-23 weeks for maternal ill health or socio-economic disadvantage, but not with terminations for fetal anomalies. Further studies need to confirm the findings concerning mirtazapine and termination of pregnancy for fetal anomalies.

Antihistamines and birth defects: a systematic review of the literature

INTRODUCTION

Approximately 10 - 15% of women reportedly take an antihistamine during pregnancy for the relief of nausea and vomiting, allergy and asthma symptoms, or indigestion. Antihistamines include histamine H1-receptor and H2-receptor antagonists.

AREAS COVERED

This is a systematic evaluation of the peer-reviewed epidemiologic literature published through February 2014 on the association between prenatal exposure to antihistamines and birth defects. Papers addressing histamine H1- or H2-receptor antagonists are included. Papers addressing pyridoxine plus doxylamine (Bendectin in the United States, Debendox in the United Kingdom, Diclectin in Canada, Lenotan and Merbental in other countries) prior to the year 2001 were excluded post hoc because of several previously published meta-analyses and commentaries on this medication.

EXPERT OPINION

The literature on the safety of antihistamine use during pregnancy with respect to birth defects is generally reassuring though the positive findings from a few large studies warrant corroboration in other populations. The findings in the literature are considered in light of three critical methodological issues: i) selection of appropriate study population; ii) ascertainment of antihistamine exposures; and iii) ascertainment of birth defect outcomes. Selected antihistamines have been very well studied (e.g., loratadine); others, especially H2-receptor antagonists, require additional study before an assessment of safety with respect to birth defect risk could be made.

First-trimester nonsystemic corticosteroid use and the risk of oral clefts in Norway

PURPOSE

Exposure of pregnant mice to corticosteroids can produce oral clefts in offspring. Although data in humans are more mixed, recent reports have suggested that dermatologic steroids are associated with oral clefts.

METHODS

We investigated maternal first-trimester exposure to corticosteroids (focusing on dermatologic uses) and oral clefts in offspring using two population-based studies. The Norway Cleft Study (1996-2001) is a national case-control study including 377 infants with cleft lip ± palate (CLP), 196 infants with cleft palate only (CPO), and 763 controls. The Norwegian Mother and Child Cohort Study (MoBa, 1998-2008) is a national birth cohort including 123 infants with CLP, 61 infants with CPO, and 551 controls.

RESULTS

In the case-control study, there was the suggestion of an association of dermatologic corticosteroids with both CLP (adjusted OR [aOR], 2.3; 95% confidence interval [CI], 0.71-7.7) and CPO (aOR, 3.4; CI, 0.87-13). There was no evidence of this association in the cohort data (odds ratio for CLP, 1.2; CI, 0.50-2.8 and odds ratio for CPO, 1.0; CI, 0.30-3.4), although exposure to dermatologic steroids was less specifically ascertained. There were no associations with other types of corticosteroids.

CONCLUSIONS

Our data add to the suggestive but inconsistent findings for this association.

Use of antiepileptic drugs during pregnancy and risk of spontaneous abortion and stillbirth: population based cohort study

OBJECTIVE

To determine whether use of antiepileptic drugs during pregnancy may increase the risk of spontaneous abortion or stillbirth.

DESIGN

Population based cohort study.

SETTING

Register based study in Denmark, 1997-2008.

PARTICIPANTS

983,305 pregnancies identified in the Danish medical birth register and the Danish national hospital discharge register from 1 February 1997 to 31 December 2008 were linked to the Danish Register of Medicinal Product Statistics to obtain information on use of antiepileptic drugs.

MAIN OUTCOME MEASURES

Risk ratio of spontaneous abortion and stillbirth after use of antiepileptic drugs during pregnancy, estimated by using binomial regression adjusting for potential confounders of maternal age, cohabitation, income, education, history of severe mental disorder, and history of drug misuse.

RESULTS

Antiepileptic drugs were used in a total of 4700 (0.5%) pregnancies. 16 out of 100 pregnant women using antiepileptics and 13 out of 100 pregnant women not using antiepileptics experienced a spontaneous abortion. After adjusting for potential confounders pregnant women using antiepileptics had a 13% higher risk of spontaneous abortions than pregnant women not using antiepileptics (adjusted risk ratio 1.13, 95% confidence interval 1.04 to 1.24). However, the risk of spontaneous abortion was not increased in women with an epilepsy diagnosis (0.98, 0.87 to 1.09), only in women without a diagnosis of epilepsy (1.30, 1.14 to 1.49). In an analysis including women with at least two pregnancies with discordant antiepileptic drug use (for example, use in the first pregnancy but not in the second), the adjusted hazard ratio for spontaneous abortion was 0.83 (0.69 to 1.00) for exposed pregnancies compared with unexposed pregnancies. Stillbirth was identified in 18 women who used antiepileptic drugs (unadjusted risk ratio 1.29, 0.80 to 2.10).

CONCLUSION

Among women with epilepsy and when analysing the risk in antiepileptic drug discordant pregnancies in the same woman, we found no overall association between the use of antiepileptic drugs during pregnancy and spontaneous abortions. Therefore unmeasured confounding may explain the slight increased risk for spontaneous abortion with any antiepileptic drug use (among women both with and without epilepsy). We found no association between antiepileptic drug use during pregnancy and stillbirth, but the statistical precision was low.

Methodological challenges in using routinely collected health data to investigate long-term effects of medication use during pregnancy

To date, the investigation of teratogenic effects of medications has largely focused on physical alterations present at birth (i.e. malformations) as opposed to functional alterations (i.e. neurodevelopment, metabolic function) that may not be apparent at birth but could influence an individual's health and risk of disease in later life. The use of routinely collected health data represents one approach to better identifying, quantifying, and understanding the long-term risks or benefits of medication use during pregnancy. As such, the objective of this review was to identify and explore opportunities and challenges associated with using routinely collected health data to examine long-term effects of medication use during pregnancy. Drawing on published research several key methodological issues associated with their use in investigating long-term outcomes are reviewed. While significant opportunities exist to make greater use of routinely collected health data, there are a number of key challenges. Identified challenges relate to aspects of study design and analysis, and include obtaining access to data, the ability to match records across datasets and over long periods of time, how medication exposures are ascertained and classified, issues around loss to follow-up how outcomes are ascertained and classified, and the careful interpretation of results in light of study and data limitations. Understanding key challenges associated with using routinely collected health data to investigate long-term effects of medication use during pregnancy is essential in supporting their appropriate use and interpretation, which will contribute to improving the quality of research undertaken and ensure the reliability of results obtained.

Identifying associations between maternal medication use and birth defects using a case-population approach: an exploratory study on signal detection

BACKGROUND

The effects of many drugs on the unborn child are unknown. In a case-population design, drug exposure of cases is compared with that of a source population; this kind of study can be useful for generating signals.

OBJECTIVE

To see whether a comparison of drug use rates from the birth defect registry EUROCAT NNL (cases) with prescription rates from a population-based prescription database, the IADB (population), could be used to detect signals of teratogenic risk of drugs.

METHODS

We defined 3,212 cases from the EUROCAT NNL database, a population-based birth defect registry in the Northern Netherlands and 29,223 population controls from the IADB, a prescription database with data from community pharmacies in the same geographical area, born between 1998 and 2008. We classified the malformations of the 3,212 cases into several malformation groups according to organ system (based on the International Classification of Diseases codes and the EUROCAT guidelines). If a child had multiple malformations in several organ systems (n = 253, 7.9 %), he/she was counted in all the categories represented. For several groups of malformations we calculated rate ratios (RR) and 95 % confidence intervals for drugs acting on the central nervous system and for drugs considered to be safe for use in pregnancy. The RRs were based on first-trimester drug use rates from the cases in the EUROCAT NNL database and prescription rates from the population controls in the IADB.

RESULTS

For drugs acting on the central nervous system we found significantly increased RRs for the anti-epileptic drug valproic acid and for some selective serotonin reuptake inhibitors. For drugs considered to be safe only the anti-hypertensive methyldopa showed significantly increased RRs.

CONCLUSION

We show that a case-population study is a suitable method for detecting signals of possible teratogenicity, provided that the teratogenic effects and the drugs under study are as specific as possible and the drugs are widely used.

Corticosteroid use and risk of orofacial clefts

BACKGROUND

Maternal use of corticosteroids during early pregnancy has been inconsistently associated with orofacial clefts in the offspring. A previous report from the National Birth Defect Prevention Study (NBDPS), using data from 1997 to 2002, found an association with cleft lip and palate (odds ratio, 1.7; 95% confidence interval [CI], 1.1-2.6), but not cleft palate only (odds ratio, 0.5, 95%CI, 0.2-1.3). From 2003 to 2009, the study population more than doubled in size, and our objective was to assess this association in the more recent data.

METHODS

The NBDPS is an ongoing multi-state population-based case-control study of birth defects, with ascertainment of cases and controls born since 1997. We assessed the association of corticosteroids and orofacial clefts using data from 2372 cleft cases and 5922 controls born from 2003 to 2009. Maternal corticosteroid exposure was based on telephone interviews.

RESULTS

The overall association of corticosteroids and cleft lip and palate in the new data was 1.0 (95% CI, 0.7-1.4). There was little evidence of associations between specific corticosteroid components or timing and clefts.

CONCLUSION

In contrast to the 1997 to 2002 data from the NBDPS, the 2003 to 2009 data show no association between maternal corticosteroid use and cleft lip and palate in the offspring.

Increasing use of antibiotics in pregnancy during the period 2000-2010: prevalence, timing, category, and demographics

OBJECTIVE

The aim of this study was to describe the use of antibiotics in a national population-based cohort of pregnant Danish women between 2000 and 2010.

DESIGN

Register-based, population-wide, cohort study.

SETTING

Denmark, from 2000 to 2010.

POPULATION

All pregnancies among Danish residents during the period 2000-2010 were included for analysis.

METHODS

Data were obtained from the Danish Medical Birth Registry, the Danish National Patient Registry, and the Registry of Medicinal Product Statistics. The filled prescriptions for systemic antibacterial, antimycotic, and antiviral drugs, as well as intravaginally applied antibiotics, were analysed. Associations with demographic variables were assessed using multivariate analysis.

MAIN OUTCOME MEASURES

Filled prescriptions for antibiotic drugs during pregnancy.

RESULTS

We included 987 973 pregnancies in Denmark from 2000 to 2010; 38.9% of women with a delivery and 14.8% of women with a miscarriage or termination of pregnancy had one or more antibiotic treatments during pregnancy. Systemic antibacterial drugs were the most frequently used drug group, with filled prescriptions for 33.4% of all deliveries and 12.6% of all abortions. This proportion increased from 28.4% in 2000 to 37.0% in 2010 among deliveries. The biggest change was seen for pivmecillinam, which increased among deliveries from 6.3% in 2000 to 19.5% in 2010. Obese (odds ratio 1.51; 95% CI 1.47-1.56), young (odds ratio 1.35; 95% CI 1.30-1.39), and low-educated women (odds ratio 1.37; 95% CI 1.35-1.1.39) tended to fill more prescriptions of antibiotics during pregnancy.

CONCLUSIONS

Overall, the number of women who filled prescriptions of antibiotics increased during the 11-year study period. In 2010, at least 41.5% of all deliveries were exposed to antibiotic therapy during pregnancy.

Nordic databases to evaluate medications in pregnancy

The objective of this review is to describe the possibilities to assess drugs used in pregnancy by means of the Nordic health registers. The Nordic countries comprise five countries: Denmark, Finland, Iceland, Norway and Sweden and have a total population of 25 million. All five countries have in their national health registers for many years recorded information concerning all births, cancer diagnoses, hospital contacts, causes of death and dispensed drugs. The registers can be used for studying drugs dispensed during pregnancy and though most previous studies focused on risks of congenital abnormalities, other health consequences of maternal medication can also be assessed.

Multiple information sources and consequences of conflicting information about medicine use during pregnancy: a multinational Internet-based survey

Background

A wide variety of information sources on medicines is available for pregnant women. When using multiple information sources, there is the risk that information will vary or even conflict.

Objective

The objective of this multinational study was to analyze the extent to which pregnant women use multiple information sources and the consequences of conflicting information, and to investigate which maternal sociodemographic, lifestyle, and medical factors were associated with these objectives.

Methods

An anonymous Internet-based questionnaire was made accessible during a period of 2 months, on 1 to 4 Internet websites used by pregnant women in 5 regions (Eastern Europe, Western Europe, Northern Europe, Americas, Australia). A total of 7092 responses were obtained (n=5090 pregnant women; n=2002 women with a child younger than 25 weeks). Descriptive statistics and logistic regression analysis were used.

Results

Of the respondents who stated that they needed information, 16.16% (655/4054) used one information source and 83.69% (3393/4054) used multiple information sources. Of respondents who used more than one information source, 22.62% (759/3355) stated that the information was conflicted. According to multivariate logistic regression analysis, factors significantly associated with experiencing conflict in medicine information included being a mother (OR 1.32, 95% CI 1.11-1.58), having university (OR 1.33, 95% CI 1.09-1.63) or other education (OR 1.49, 95% CI 1.09-2.03), residing in Eastern Europe (OR 1.52, 95% CI 1.22-1.89) or Australia (OR 2.28, 95% CI 1.42-3.67), use of 3 (OR 1.29, 95% CI 1.04-1.60) or >4 information sources (OR 1.82, 95% CI 1.49-2.23), and having ≥2 chronic diseases (OR 1.49, 95% CI 1.18-1.89). Because of conflicting information, 43.61% (331/759) decided not to use medication during pregnancy, 30.30% (230/759) sought a new information source, 32.67% (248/759) chose to rely on one source and ignore the conflicting one, 25.03% (190/759) became anxious, and 2.64% (20/759) did nothing. Factors significantly associated with not using medication as a consequence of conflicting information were being pregnant (OR 1.75, 95% CI 1.28-2.41) or experiencing 3-4 health disorders (OR 1.99, 95% CI 1.10-3.58). Women with no chronic diseases were more likely not to take medicines than women with ≥2 chronic diseases (OR 2.22, 95% CI 1.47-3.45). Factors significantly associated with becoming anxious were >4 information sources (OR 2.67, 95% CI 1.70-4.18) and residing in Eastern Europe (OR 0.57, 95% CI 0.36-0.90).

Conclusions

Almost all the pregnant women used multiple information sources when seeking information on taking medicines during pregnancy and one-fifth obtained conflicting information, leading to anxiety and the decision not to use the medication. Regional, educational, and chronic disease characteristics were associated with experiencing conflicting information and influenced the decision not to use medication or increased anxiety. Accurate and uniform teratology information should be made more available to the public.

Antidepressant exposure in pregnancy and risk of autism spectrum disorders

Background

Both the use of antidepressant medication during pregnancy and the prevalence of autism spectrum disorder have increased during recent years. A causal link has recently been suggested, but the association may be confounded by the underlying indication for antidepressant use. We investigated the association between maternal use of antidepressant medication in pregnancy and autism, controlling for potential confounding factors.

Methods

We identified all children born alive in Denmark 1996–2006 (n=668,468) and their parents in the Danish Civil Registration System. We obtained information on the mother’s prescriptions filled during pregnancy from the Danish National Prescription Registry, and on diagnoses of autism spectrum disorders in the children and diagnoses of psychiatric disorders in the parents from the Danish Psychiatric Central Register. In a cohort analysis, we estimated hazard ratios of autism spectrum disorders in children exposed to antidepressant medication during pregnancy compared with children who were not exposed, using Cox proportional hazards regression analysis. Furthermore, we estimated the risk for autism spectrum disorder in a sibling design.

Results

Children exposed prenatally to antidepressants had an adjusted hazard ratio of 1.5 (95% confidence interval [CI] 1.2–1.9) for autism spectrum disorder compared with unexposed children. Restricting the analysis to children of women with a diagnosis of affective disorder, the adjusted hazard ratio was 1.2 (95% CI 0.7–2.1), and the risk was further reduced when exposed children were compared with their unexposed siblings (adjusted hazard ratio 1.1; 95% CI 0.5–2.3).

Conclusion

After controlling for important confounding factors, there was no significant association between prenatal exposure to antidepressant medication and autism spectrum disorders in the offspring.

Risk factors for venous thromboembolism during pregnancy

BACKGROUND

Pregnant women are at an increased risk of venous thromboembolism (VTE). Risk factors for VTE among pregnant women are not sufficiently investigated.

PURPOSE

To examine pharmacological and non-pharmacological VTE risk factors during pregnancy (antepartum).

METHODS

The population comprised all pregnant women in Denmark aged 15-50 giving birth 2003-2010. Pregnancies were linked on an individual level with national registers for hospital admissions and drug dispenses from pharmacies. Risk of first occurring VTE antepartum was examined with Cox regression models.

RESULTS

Out of 299 810 pregnancies, 337 experienced a VTE, incidence rate 1.1 (95% confidence interval [CI] 1.0-1.3) per 1000 pregnancies. Being underweight (body mass index [BMI] < 18.5 kg/m(2) ) was associated with a decreased risk of VTE (hazard ratio [HR] 0.53 [CI 0.29-0.98]) compared to normal weight (18.5 ≤ BMI < 25 kg/m(2) ). Overweight (25 ≤ BMI < 30 kg/m(2) ) increased VTE risk (HR 1.30 [CI 1.01-1.67]) but obesity (BMI ≥ 30 kg/m(2) ) was insignificant (HR 1.14 [CI 0.82-1.58]). A history of VTE was highly significant (HR 72.65 [CI 51.17-103.15]). The youngest (<20 years) and oldest (≥35 years) had insignificantly increased risks (HR 1.45 [CI 0.80-2.62] and HR 1.31 [CI 0.98-1.75], respectively) compared to those aged 20-30 years. Sixteen groups of medications, including anti-infectious medications, hormones, aminosalicylic acid, insulin, and benzodiazepine derivatives, were associated with VTE.

CONCLUSION

The risk of antepartum VTE was increased in women with prior VTE. Compared to normal weight women, being underweight decreased the risk of VTE whereas being overweight increased the risk. Also, the use of several medications was associated with increased risk of VTE.