Medications used disproportionately during pregnancy: Priorities for research on the risks and benefits of medications when used during pregnancy

Racial Disparities in Medication Use During Pregnancy: Results from the NISAMI Cohort

Purpose

This study aimed to evaluate racial disparities in medication use and associated factors among pregnant women receiving prenatal care at Brazilian Unified Health System primary care health units in the northeast region.

Patients and Methods

A total of 1058 pregnant women in the NISAMI Cohort were interviewed between June 2012 and February 2014. Medicines used during pregnancy were classified according to the Anatomical Therapeutic Chemical (ATC) classification system and ANVISA pregnancy risk categories. Prevalence ratios (crude and adjusted) and 95% confidence intervals (CIs) were estimated using Poisson regression with robust error variance. All analyses were stratified by race (Asian, black, brown/mixed, Brazilian indigenous, and white).

Results

Approximately 84% of the pregnant women used at least one medication, with a lower proportion among white women. The most reported medications were antianemic preparations (71.08%; 95% CI 68.27-73.72%), analgesics (21.74%; 95% CI 19.36-24.32%), and drugs for functional gastrointestinal disorders (18.81%; 95% CI 16.57-21.28%). Approximately 29% of women took potentially risky medications during pregnancy, with a higher prevalence among Asian and white women. Factors associated with medication use during pregnancy include a greater number of prenatal consultations, higher education levels, health problems, and smoking. In addition, maternal age above 25 years, smoking status, and two or more previous pregnancies were associated with potentially risky medication use during pregnancy.

Conclusion

A high prevalence of medication use during pregnancy was found; however, this prevalence was lower among white women. Nonetheless, black and brown women used antianemic preparations less frequently. This finding suggests that race is a factor of inequity in prenatal care, demanding public policies to mitigate it.

Use of privacy-preserving record linkage to examine the dispensing of pharmaceutical benefits scheme medicines to pregnant women in Western Australia

PURPOSE

Medications are commonly used during pregnancy to manage pre-existing conditions and conditions that arise during pregnancy. However, not all medications are safe to use in pregnancy. This study utilized privacy-preserving record linkage (PPRL) to examine medications dispensed under the national Pharmaceutical Benefits Scheme (PBS) to pregnant women in Western Australia (WA) overall and by medication safety category.

METHODS

In this retrospective, cross-sectional, population-based study, state perinatal records (Midwives Notification Scheme) were linked with national PBS dispensing data using PPRL. Live and stillborn neonates born between 2012 and 2019 in WA were included. The proportion of pregnancies during which the mother was dispensed a PBS medication was calculated, overall and by medication safety category. Factors associated with PBS medication dispensing were examined using logistic regression.

RESULTS

PPRL linkage identified matching records for 97.4% of women with perinatal records. A total of 271 739 pregnancies were identified, with 158 585 (58.4%) pregnancies involving the dispensing of at least one PBS medication. Category A medications (those considered safe in pregnancy) were the most commonly dispensed (n = 119 126, 43.8%) followed by B3 (n = 51 135, 18.8%) and B1 (n = 42 388, 15.6%) medication (those with unknown safety). Over the study period, the dispensing of PBS medications in pregnancy increased (OR: 1.06, 95%CI: 1.06, 1.07). The strongest predictor of medication dispensing in pregnancy was pre-pregnancy dispensing (OR: 3.61, 95%CI: 3.54, 3.68). Other factors associated with medication use in pregnancy were smoking, older maternal age, obesity, and prior pregnancies.

CONCLUSION

Privacy preserving record linkage provides a way to link cross-jurisdictional data while preserving patient confidentiality and data security. The dispensing of PBS medication in pregnancy was common and increased over time, with approximately 60% of women dispensed at least one medication during pregnancy.

Pharmacoepidemiology and costs of medications dispensed during pregnancy: A retrospective population-based study

OBJECTIVE

To describe the pharmacoepidemiology and costs associated with medications dispensed during pregnancy.

DESIGN

Pharmacoepidemiological study and cost analysis.

SETTING

Queensland, Australia.

POPULATION

All women who gave birth in Queensland between January 2013 and June 2018.

METHODS

We used a whole-of-population linked administrative dataset, Maternity1000, to describe medications approved for public subsidy that were dispensed to 255 408 pregnant women. We describe the volume of medications dispensed and their associated costs from a Government and patient perspective.

MAIN OUTCOME MEASURES

Prevalence of medication use; proportion of total dispensings; total medication costs in AUD 2020/21 ($1AUD = $0.67USD/£0.55GBP in December 2022).

RESULTS

During pregnancy, 61% (95% CI 60.96-61.29%) of women were dispensed at least one medication approved for public subsidy. The mean number of items dispensed per pregnancy increased from 2.14 (95% CI 2.11-2.17) in 2013 to 2.47 (95% CI 2.44-2.51) in 2017; an increase of 15%. Furthermore, mean Government cost per dispensing increased by 41% from $21.60 (95% CI $20.99-$22.20) in 2013 to $30.44 (95% CI $29.38-$31.49) in 2017. These factors influenced the 53% increase in total Government expenditure observed for medication use during pregnancy between 2013 and 2017 ($2,834,227 versus $4,324,377); a disproportionate rise compared with the 17% rise in women's total out-of-pocket expenses observed over the same timeframe ($1,880,961 versus $2,204,415).

CONCLUSIONS

Prevalence of medication use in pregnancy is rising and is associated with disproportionate and rapidly escalating cost implications for the Government.

Prevalence of polypharmacy in pregnancy: a systematic review

OBJECTIVES

The use of medications among pregnant women has been rising over the past few decades but the reporting of polypharmacy has been sporadic. The objective of this review is to identify literature reporting the prevalence of polypharmacy among pregnant women, the prevalence of multimorbidity in women taking multiple medications in pregnancy and associated effects on maternal and offspring outcomes.

DESIGN

MEDLINE and Embase were searched from their inception to 14 September 2021 for interventional trials, observational studies and systematic reviews reporting on the prevalence of polypharmacy or the use of multiple medications in pregnancy were included.Data on prevalence of polypharmacy, prevalence of multimorbidity, combinations of medications and pregnancy and offspring outcomes were extracted. A descriptive analysis was performed.

RESULTS

Fourteen studies met the review criteria. The prevalence of women being prescribed two or more medications during pregnancy ranged from 4.9% (4.3%-5.5%) to 62.4% (61.3%-63.5%), with a median of 22.5%. For the first trimester, prevalence ranged from 4.9% (4.7%-5.14%) to 33.7% (32.2%-35.1%). No study reported on the prevalence of multimorbidity, or associated pregnancy outcomes in women exposed to polypharmacy.

CONCLUSION

There is a significant burden of polypharmacy among pregnant women. There is a need for evidence on the combinations of medications prescribed in pregnancy, how this specifically affects women with multiple long-term conditions and the associated benefits and harms.

TWEETABLE ABSTRACT

Our systematic review shows significant burden of polypharmacy in pregnancy but outcomes for women and offspring are unknown.

PROSPERO REGISTRATION NUMBER

CRD42021223966.

The association between psychostimulant use in pregnancy and adverse maternal and neonatal outcomes: results from a distributed analysis in two similar jurisdictions

BACKGROUND

Conflicting evidence suggests a possible association between use of prescribed psychostimulants during pregnancy and adverse perinatal outcomes.

METHODS

We conducted population-based cohort studies including pregnancies conceived between April 2002 and March 2017 (Ontario, Canada; N = 554 272) and January 2003 to April 2011 [New South Wales (NSW), Australia; N = 139 229]. We evaluated the association between exposure to prescription amphetamine, methylphenidate, dextroamphetamine or lisdexamfetamine during pregnancy and pre-eclampsia, placental abruption, preterm birth, low birthweight, small for gestational age and neonatal intensive care unit admission. We used inverse probability of treatment weighting based on propensity scores to balance measured confounders between exposed and unexposed pregnancies. Additionally, we restricted the Ontario cohort to social security beneficiaries where supplementary confounder information was available.

RESULTS

In Ontario and NSW respectively, 1360 (0.25%) and 146 (0.10%) pregnancies were exposed to psychostimulants. Crude analyses indicated associations between exposure and nearly all outcomes [OR range 1.15-2.16 (Ontario); 0.97-2.20 (NSW)]. Nearly all associations were attenuated after weighting. Pre-eclampsia was the exception: odds remained elevated in the weighted analysis of the Ontario cohort (OR 2.02, 95% CI 1.42-2.88), although some attenuation occurred in NSW (weighted OR 1.50, 95% CI 0.77-2.94) and upon restriction to social security beneficiaries (weighted OR 1.24, 95% CI 0.64-2.40), and confidence intervals were wide.

CONCLUSIONS

We observed higher rates of outcomes among exposed pregnancies, but the attenuation of associations after adjustment and likelihood of residual confounding suggests psychostimulant exposure is not a major causal factor for most measured outcomes. Our findings for pre-eclampsia were inconclusive; exposed pregnancies may benefit from closer monitoring.