top of page

Reducing Risk: Tackling the Complex Causes of Preterm Birth in Canada

Preterm birth is a major global public health issue with 1 in 10 babies [1] (Blencowe et al, 2012)  born prematurely worldwide. Today let’s discuss the stats that Canadian women should know, from the rates of preterm birth to research on risk factors that increase risk. While the Canadian health care system is equipped to care for preterm infants with access to advanced neonatal intensive care units and technologies, preterm birth remains a leading cause of infant mortality and long-term disabilities. Canadian families still face tremendous stress, grief, and financial costs due to preterm births and preterm infants are at higher risk for disabilities and health complications long term.


Preterm Birth Statistics

Preterm Birth(PTB) rates vary by country, ranging from a low of 5% in some European countries to 18% in some African countries. Preterm birth is also prevalent in North America with a ~10% rate in the United States, with African American mothers carrying a 50% increased risk rate at 14.59%[2] (Martin et al. 2022). Canada’s overall rate is ~8% [3].


Insert Graph StatsCan



Preterm Birth (PTB)

& Small for Gestational Age (SGA)

Too Early, To Small: a Profile of Small Babies Across Canada[4] is an excellent public resource developed by the Canadian Institute for Health Information in 2009 that gives clear statistics on PTB and SGA in Canada for 2006-7 and what was known at the time. We’ll look at a few groundbreaking studies that have only been completed in the last few years, changing guidelines and bringing hope to bear on this difficult issue.


In 2006–2007, the preterm birth rate in Canada was approximately 8.1%, accounting for over 54,000 live preterm births, highlighting this significant public health issue. In 2022 it was 8.2%[3] leaving us wondering why no progress has been made in 15 years.


A key factor affecting preterm birth in Canada is maternal age. The highest preterm birth rates were associated with mothers aged 35 and older (9.5%) with first-time mothers aged 35 years and older demonstrating the highest rate (11.6%) of delivering a baby that is small for gestational age (SGA).[4] 


Existing maternal health conditions increase the risk of preterm birth.  PTB and SGA babies born in Canada (excluding Quebec) were born to mothers with diabetes (5.1%) and hypertensive disorders of pregnancy (HDP) like preeclampsia (6.2%).

 

Preterm birth rates were also significantly higher for women with a pre-existing condition, compared to women whose conditions developed during pregnancy. 


We predict new treatment protocols for Hypertensive Disorders of Pregnancy (HDP) and preeclampsia are coming soon thanks to the groundbreaking PRISM trial [7] (Coomarasamy et al, 2020). PRISM data has been used to investigate ways to decrease HDP by 29% and preeclampsia by 39%, while providing the criteria for a target population of women. [9] (Melo et al, 2023). This might meaningfully decrease PTB in future years.

 

Income level also seems to play a role. Older women and those living in higher-income neighborhoods were more likely to have multiple births, which are strongly associated with preterm delivery as more than half of twins and almost all higher-order multiples are born preterm.


Only now is there published research showing that ARTs increase preterm birth odds significantly, partially by causing higher order multiple pregnancies (as of 2015, 13% of IVF pregnancies in Canada are multiples, outside of Quebec which is publicly funding IVF to enforce single embryo transfer). []


Increased odds of preterm birth are now reported as 4.24X odds for IVF, 3.17X odds for IUI and 2.17 for ovulation inducing drugs [6] (Sanders et al, 2022). 


These multiple factors intersect to shape a woman's risk profile for preterm delivery in Canada, especially advanced age, infertility necessitating use of ARTs for conception and pre-existing health conditions. Better research to understand how these factors contribute is an important step in developing effective interventions. More research has certainly be done since 2012, leading to new guidelines for identifying higher risk expectant mothers in Canada through the Guidance document “Progesterone for Prevention of Spontaneous Preterm Birth [8] (Jain et al., 2020), produced by the Maternal–Fetal Medicine Committee of the Society of Obstetricians and Gynaecologists of Canada (SOGC). 


It’s an excellent resource that helps evaluate the evidence that underlies pregnancy monitoring & support programs like ProSPr. 


Leading Risk Factors for Preterm Birth

The two main risk factors for PTB8 :

  1. Prior preterm birth

  2. Short cervix of less than 25 mm before 24 weeks gestation


New Treatment Guidelines

Guidelines for treatment protocols for singleton and multiple pregnancies are already in place. For women with major risk factors, moderate to strong evidence exist that interventions such as progesterone therapy may help reduce their risk of another preterm birth with therapy starting as early as 16 weeks and carried through to 34-36 weeks gestation.[8] (Jain et al, 2020)


Progesterone & Thyroid Support in Pregnancy (ProSPr)

My Fertility Lab’s Progesterone & Thyroid Support in Pregnancy (ProSPr) is based on restorative reproductive medicine and provides lab monitoring of progesterone and thyroid levels throughout pregnancy, along with bioidentical progesterone and thyroid supplementation when needed, monitored by one of our clinicians.


The goal of the program is to optimize progesterone and thyroid function for women with indicators of high risk pregnancies, to help prevent miscarriage and support a healthy pregnancy to term. This is especially relevant for women at higher risk due to a history of infertility, previous preterm birth or previous pregnancy complications like preeclampsia. Progesterone is often recommended treatment for those at higher risk of preterm birth.


Key benefits of the My Fertility Labs program for high-risk pregnancies include:


- Personalized care and treatment based on the patient's lab results and medical history

- Ongoing lab monitoring of hormone levels

- Prescription bio-identical hormones to help sustain pregnancy

- Pre-conception care to correct underlying dysfunction supporting a healthier pregnancy and healthy baby


By taking a proactive, preventive approach, the program aims to identify and treat issues early that could otherwise threaten the pregnancy. This represents a more progressive, functional medicine model of care, compared to simply waiting for problems to occur before intervening.


Preterm Birth Rates in Canada - Can they Decrease?

Preterm birth is a critical public health issue that affects millions of babies worldwide each year. Although there has been some progress in reducing rates in a few countries in Europe, preterm birth remains persistently high in many regions. 


Canada's preterm birth rate has remained around 8% for the past two decades with several factors contributing to preterm birth risk in Canada, including advanced maternal age, pre-existing medical conditions like diabetes and hypertension, and multiple births [4,5,6]


Preterm birth can have devastating consequences for infants who may face chronic health issues throughout life. There is an urgent need for greater awareness, education, research, and support services to combat this pressing problem. Health professionals, policymakers, and the public must work together to implement comprehensive preterm birth prevention strategies and new research has illuminated a path [7,8,9]


Interventions should focus on improving preconception, and prenatal health, especially among higher risk groups. With coordinated efforts, Canada can make progress in lowering its preterm birth rate and giving more infants a healthy start in life.


Written by Carolyn Plican, Creighton Model FertilityCare Practitioner

Reviewed by Dr. Mary Ellen Haggerty, Restorative Reproductive Medicine Clinician


[1] Blencowe, H.; Cousens, S.; Oestergaard, M.Z.; Chou, D.; Moller, A.-B.; Narwal, R.; Adler, A.; Garcia, C.V.; Rohde, S.; Say, L.; et al. National, regional, and worldwide estimates of preterm birth rates in the year 2010 with time trends since 1990 for selected countries: A systematic analysis and implications. Lancet 2012, 379, 2162–2172. https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(12)60820-4/fulltext?cc=y

[2] Martin JA, Hamilton BE, Osterman MJK. Births in the United States, 2022. NCHS Data Brief, no 477. Hyattsville, MD: National Center for Health Statistics. 2023. DOI: https://dx.doi.org/10.15620/cdc:131354

[3] Statistics Canada. (2023). Live births, by weeks of gestation (Table 13-10-0425-01). Retrieved from https://www150.statcan.gc.ca/t1/tbl1/en/tv.action?pid=1310042501

[4]Canadian Institute for Health Information. (2009). Too Early, Too Small: A Profile of Small Babies Across Canada. https://secure.cihi.ca/free_products/too_early_too_small_en.pdf

[5] Medical Advisory Secretariat. In vitro fertilization and multiple pregnancies: an evidence-based analysis. Ont Health Technol Assess Ser. 2006;6(18):1-63. Epub 2006 Oct 1. PMID: 23074488; PMCID: PMC3379537.

[6] Sanders JN, Simonsen SE, Porucznik CA, Hammoud AO, Smith KR, Stanford JB. Fertility treatments and the risk of preterm birth among women with subfertility: a linked-data retrospective cohort study. Reprod Health. 2022 Mar 29;19(1):83. doi: 10.1186/s12978-022-01363-4. PMID: 35351163; PMCID: PMC8966354.

[7] Coomarasamy A, Harb HM, Devall AJ, Cheed V, Roberts ET, Goranitis I, et al. Progesterone to prevent miscarriage in women with early pregnancy bleeding: the PRISM RCT. Health Technol Assess 2020;24(33)           

[8]Jain, V., McDonald, S. D., Mundle, W. R., & Farine, D. (2020). Guideline No. 398: Progesterone for prevention of spontaneous preterm birth. SOGC Clinical Practice Guideline, 42(6), 806-812. https://doi.org/10.1016/j.jogc.2019.04.012

[9]Melo, P.; Devall, A.; Shennan A.H.; Vatish, M.; Becker, C.M.; Granne, I.; Papageorghiou, A.T.; Mol, B. & Coomarasamy, A. (2023) Vaginal micronised progesterone for the prevention of hypertensive disorders of pregnancy: A systematic review and meta-analysis, BJOG, https://doi.org/10.1111/1471-0528.17705

[10] Canadian Fertility and Andrology Society. Canadian ART Register. Retrieved [1.11.2024], from https://cfas.ca/canadian-art-register.html


1 view0 comments
bottom of page