by Rtn. Vincent T. C. Leung, MBBS, FRCP, FRCPCH, DCH, FHKCP, FHKAM(Paediatrics), RC of HK Island West

Hon. Consultant, Neonatal Nursery, HK Baptist Hospital

The recent influx of mainland mothers in Hong Kong has highlighted the respiratory complications to the newborn as a result of Ceasarean Section (C/S) deliveries.  With their one week travel visa, most mainland mothers will opt for elective C/S usually at just 37 weeks of gestation so that the newborn can be delivered and identity cards completed within one week.  This has led to a dramatic increase in respiratory complications e.g. wet lung syndrome, respiratory distress syndrome and pneumothorax (rupture of lungs)etc.  in the newborns leading to a rise in morbidity and mortality.

As nearly 70 -80% of babies delivered in private hospitals are by C/S, such complications has led to the overload of the neonatal intensive care (NICU) service  in the public hospitals as most mainlanders cannot afford NICU care in private hospitals.

In a study of over 3000 newborns which we have carried out in Baptist Hospital in 2009, babies delivered by C/S  has a 4.7 times increase in respiratory complications compared to normal vaginal delivery.  This compares to 2.2 times in the USA where C/S is only carried out after 39 wks of gestation or after the onset of labour.

The biggest challenge a newborn faces at birth is to make a fast transition from fluid filled lungs in utero to lungs filled with air after birth.  Failure to clear the lung fluids is problematic in elective C/S without onset of labour.  Physiological  events in the last few weeks of pregnancy, coupled with the onset of spontaneous labour are accompanied  by changes in the hormonal environment of the mother and fetus.  These will  result in the preparation of the fetus for birth transition. Lung fluid production is reduced a few days prior to onset of labour as nature prepares the fetus for extra-uterine life.  Further passage through the birth canal will squeeze out excess lung fluids and newborns’ lung can expand naturally.

With elective C/S esp. at 37 weeks of gestation, retained lung fluids will give rise to a much higher incidence of wet lung syndrome( from retained lung fluids), respiratory distress syndrome (failure of the lungs to expand) and other lung complications.  As C/S by itself can reduce birth injury to the fetus and some maternal complications, more parents tend to opt for elective C/S.

In order to strike a balance, in late 2010, Baptist Hospital has mandated that elective C/S can only be carried out after 38 wks of gestation unless there are medical indications or onset of labour. Since then an analysis of the 12,000 babies delivered in 2011, the number of newborns requiring transfer to public hospitals has reduced by 60% and the incidence of respiratory complications reduced by 50%.

As Hong Kong is facing a low birth rate because of late marriages, high maternal age, in vitro fertilization, precious baby  etc,  elective C/S is getting more common in private hospitals of up to 80% compared to around 30-40% in western countries.    Unnecessary respiratory complications will continue to affect our newborns unless C/S is medically indicated or is carried out after onset of labour and if possible after a gestation of 38weeks or more.

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Dr Vincent Leung would like to thank your support allowing him to get into the final round of the Loving Heart HK Competition. Please note voting for the final will last until 17th Nov. If you would like to vote for Dr Leung, please submit your sacred vote via the link below:

http://www.hkatv.com/v5/13/hklovingheart2013/index.html.