Journal Publications

OBJECTIVE: To describe the normative serum cortisol levels during 25-29 weeks of POG and the association of maternal, psychological, and social factors on serum cortisol in the second and third trimesters in a cohort of pregnant women. METHODS: All eligible pregnant women registered in the maternal care program in Anuradhapura district, Sri Lanka, from July to September 2019 were invited to the Rajarata Pregnancy Cohort (RaPCo). An interviewer-administered questionnaire-based symptom analysis and clinical assessment were conducted at baseline in the first trimester and at follow-up from 25 to 29 weeks POG. We assessed fasting early morning serum cortisol levels at the follow-up visit. RESULTS: The study sample included 1010 pregnant women with a mean age in years and POG in weeks at baseline of 28 (+/-6) and 10 (+/-3), respectively. The mean (SD, 97% percentile) serum cortisol level in all pregnant women was 10.93 (+/-3.83, 20.95) mug/dL, with no significant difference between singleton and twin pregnancies (p = 0.138). None of the study participants had a cortisol level exceeding the upper limit of 42 mug/dL, and 464 (45.9%) had levels less than 10 mug/dL. Serum cortisol levels were higher in women with an advanced POG, with a mean of 10.33 microg/dL (95%CI: 9.68-10.98) at 24 weeks POG and 12.23 microg/dL (95%CI: 11.15-13.32) at 29 weeks POG (p = 0.049). Primi-gravidity (p = 0.004), history of miscarriage (p = 0.010), BMI categories (p = 0.044), and POG (p = 0.002) were independently associated with serum cortisol levels in robust regression. An EPDS score of more than 9 was not associated with serum cortisol (p = 0.633). CONCLUSION: The pregnant women in rural Sri Lanka reported a low mean serum cortisol level, which gradually increased with the POG. Significantly higher mean serum cortisol was associated with primi-gravidity, history of miscarriage, pre-pregnancy BMI, and POG at cortisol test, but not psychological factors.