Fifty pregnant female subjects aged 20-35 yrs in the third trimester of their pregnancy and reportedly snoring during sleep who were attending the ante-natal out patients department (ANC OPD) of Safdarjang Hospital were recruited into the study (study group). An equal number of non-snoring pregnant females of the same age group who were attending the same OPD were taken as controls. They were asked to respond to a standard sleep questionnaire that was based on sleep apnea scale (SAS)3 and Epworth sleepiness scale (ESS). All the subjects in the study group underwent a sleep study (polysomnography) after evaluation of questionnaire. Respiratory distress index (RDI) was calculated as a sum of apnea, hypopnea and flow limitations. The study and control groups were followed during pregnancy and labour. Comparison of complications and outcomes of pregnancy in mother and fetus was done among the study and control groups. Parameters specifically looked for were development of preeclampsia and eclampsia, IUGR, and lower Apgar score
Incidence of bad obstetric history, pre-term delivery and post-term delivery were not statistically different among snorers and non snorers. Incidence of pre-eclampsia was 30.3% in snorers as compared to 9.1% in non snorers (p = 0.004). Incidence of meconium-stained liquor was 27.2% in snorers and 6.8% in non snorers (p =0.005) Incidence of Apgar score < 7 was high in babies born to snorers as compared to non snorers. 36.3% babies born to snorers had Apgar score < 7 in comparison to only 14.94% born to non snorers (p = 0.025). Incidence of low birth weight was also more in babies born to snorers (30%) as compared to non-snorers (13.79%) (p = 0.037). Incidence of pre-eclampsia increased with increase in RDI values. 9.09% of snorers had non-progression of labour (NPOL) as opposed to 4.9% in non-snorers. Among snorers 24.2% landed up into Caesarian delivery in comparison to 11.8% of non-snorers (p=0.076). Mean birth weight of babies born to snorers and non-snorers were 2660+443.2 gm and 2801+378.3 gm respectively (p=0.086, 95% CI=-301.4 – 20.02). Mean Ponderal index was 3.04+0.4 in babies of snorers as compared to 2.97+0.4 in non-snorers (p=0.491, 955 CI= -0.126 –0.261).
Snoring and sleep disordered breathing (SDB) are extremely common conditions that compromise the vital functions of respiration and circulation. SDB has widespread systemic effects that include adverse impact on maternal and fetal outcomes of pregnancy.
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