Optimal pregnancy spacing for high-risk obstetric populations
Closely spaced pregnancies have poor maternal and infant outcomes. Existing guidelines recommend waiting from at least 18 to 24 months following previous childbirth until becoming pregnant again. It is not known, however, whether these guidelines suitable for all women. Women with a prior history of poor outcomes might have different optimal interpregnancy interval pertinent to them and waiting for 18 months might be associated with adverse outcomes. For example, among women who had pregnancy loss, current recommendations to wait 18 months before their next pregnancy may prolong their grief and emotional stress, whereas for women with a history of subfertility, waiting the recommended 18 months may increase their risk of infertility due to advancing maternal age.

In this project, we will study whether associations between short intervals and adverse outcomes are the same or different among women with poor outcomes in the first pregnancy (fetal or newborn death, history of infertility treatment, or preterm delivery) and among women with good outcomes in the first pregnancy. This will help us to create guidelines on optimal birth spacing for women with the poor outcomes in their first pregnancies. We will use a high-quality, population-based cohort including all pregnancies in British Columbia from 2004 to 2014 to examine relationships between pregnancy spacing interval and adverse outcomes (fetal or newborn mortality, poor fetal growth, preterm delivery) for women with a fetal or newborn death, infertility treatment, or preterm birth in the first pregnancy. Study findings will inform women’s and families’ pregnancy spacing decisions to achieve the best pregnancy outcomes they can. These findings will guide clinicians providing counselling on optimal pregnancy spacing for women in these high-risk groups. Optimal pregnancy spacing for these high-risk populations may enable prevention of recurrent complications (preterm delivery or fetal/neonatal death) and improve fetal and infant health outcomes in each of these groups.

Postpartum prescription opioid use
There are growing concerns that opioid prescriptions related to childbirth may be contributing to the opioid epidemic. In the US, over 50% of opioid-naive women are prescribed an opioid in the postpartum period, including 80% after cesarean delivery and 29% after vaginal delivery. Of these, 1-2% are still using an opioid 6 months postpartum. Postpartum opioid prescribing has been identified as a potential clinical area in which new opioid prescribing could be reduced, particularly to prevent new long-term or chronic opioid use in this population. To this end, the American College of Obstetricians and Gynecologists published clinical postpartum pain management guidelines in 2018, which recommend multimodal pain management approaches that reserve opioids for breakthrough pain relief. These recommendations emphasize the importance of postpartum pain treatment to reduce risks of postpartum depression and other adverse outcomes.

In Canada, however, our understanding of postpartum use of prescription opioids is limited. The frequency of opioid prescribing after cesarean or vaginal delivery in Canada is not known, nor how frequently initial postpartum opioid prescriptions progress to persistent opioid use. The Society of Obstetricians and Gynecologists of Canada (SOGC) has published guidelines on pregnancy care for women using opioids in pregnancy, but has no specific recommendations for postpartum pain management. Patterns of opioid prescribing after routine surgery (laparoscopic cholecystectomy, laparoscopic appendectomy, arthroscopic knee meniscectomy, and breast excision) are similar between the U.S. and Canada, at 76% and 79% respectively. However, there are many differences in obstetrical practice between the U.S. and Canada, so it is not clear whether postpartum pain management practices are similar or different between these jurisdictions.

The objectives of this study are to determine the frequency of postpartum prescription opioid dispensation and progression to long-term use in British Columbia, variation by obstetric and sociodemographic characteristics, and temporal trends. Optimal postpartum pain management (including judicious use of prescription opioids) may facilitate mother-infant bonding, breastfeeding success, and long-term health of the mother-infant dyad.

Health policy impacts on pregnancy timing and spacing
Inadequate and inequitable access to contraception services have limited the ability for populations across Canada to optimally time and space their pregnancies. For equity deserving populations, particularly rural and remote, adolescent, gender-diverse, and racialized groups, inadequate access to the most effective contraception is a barrier to preventing unplanned pregnancy – a key reproductive population health indicator. In these groups, mistimed or unwanted pregnancies continue to be frequent, leading to poor reproductive outcomes, exacerbating health inequity, and limiting economic gender equity.

The most effective forms of contraception are long-acting reversible contraception, which includes intrauterine contraceptive devices (IUDs) and sub-dermal contraceptive implants. To date, evidence on long-acting reversible contraception access and uptake in Canadian health systems is sparse. Existing evidence is limited to surveys conducted during time periods prior to implant availability, leaving wide knowledge gaps regarding contraception access in Canada. The consequence of this gap is that health system and policy leaders have little evidence to guide policy and care delivery improvements.

This study will use BC’s population-based administrative health data to generate urgently needed evidence for health policymakers and system decision-makers. We will analyze a population-based cohort of contraception service providers and reproductive-aged females from 2016-2022 to:

1. Describe the geographic distribution and characteristics of the contraception workforce and trends over time.
2. Identify the frequency and characteristics of “contraception deserts”, i.e., geographic regions lacking adequate access to long-acting reversible contraception services.
3. Describe long-acting reversible contraception users, populations with lowest uptake, and trends over time in long-acting reversible contraception use.

This study will support policy implementation, development, and revision to target geographic regions, population groups, and clinician professional development to improve contraception access. This lays the foundation for a learning health system approach to further policy evaluation and adaptation to ensure equitable access to the most effective contraception. By improving access to effective contraception, this study will enable populations to plan their pregnancies and births, leading to improved fetal and infant outcomes.