Background: Pregnancy induced hypertension is one of the most common causes of both maternal and neonatal morbidity affecting about 5 – 8% of pregnant women. There are various risk factors for the development of pregnancy induced hypertension. Obesity is increasing at a higher rate in Kerala. Clinical thyroid dysfunction has been associated with pregnancy complications such as hypertension. Snoring is more common in pregnant women compared to non pregnant women. There are only a few studies demonstrating the association of these risk factors with pregnancy induced hypertension in South Indian population.

Objective: To assess the association of hypothyroidism, maternal obesity, self reported snoring as risk factors for pregnancy induced hypertension in patients admitted in antenatal wards in Sree Avittom Thirunal Hospital, Thiruvananthapuram.

Method: This was a case control study involving 50 pregnant women in third trimester diagnosed with pregnancy induced hypertension and 50 normal pregnant women in third trimester without any previous disorders or pregnancy induced complications. Serum TSH and FT4 levels were assessed by chemiluminescentimmuno assay with Beckman Access 2 immunoassay system. Other variables like snoring assessed by providing a questionnaire for snoring to the subjects. BMI assessed by collecting data regarding height and weight from previous visits records. Clinical evaluation involved a proforma based interview with regard to age, parity, history of any other diseases.

Results: Maternal obesity was significantly noted in women diagnosed with pregnancy induced hypertension when compared to normal pregnant women (p<0.001, OR 7.21, CI 2.72-19.1).Pregnant women with history of snoring had significantly higher risk of pregnancy induced hypertension. Obesity and age were independent risk factors of snoring in pregnancy. Elevated TSH levels were found to be significantly associated with pregnancy induced hypertension (p<0.001).

Conclusion: Maternal obesity, self reported snoring and elevated TSH levels (TSH>3mIU/L) can be risk factors for pregnancy induced hypertension.

Keywords: Pregnancy induced hypertension; maternal obesity; snoring; case control study.

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Dr Sahila M

Professor, Dept of Physiology, Govt Medical College, Trivandrum, India