Practice News

November 2012

November 2012

Last month the findings of a preliminary study by a clinical research group from Sydney that pregnant women who sleep on their backs may increase their stillbirth risk was released to the popular press.

As you can imagine this created some anxiety in pregnant women who woke during their sleep to find that they were lying on their backs!

The well known physiological observation that in late pregnancy lying on the right side or on the back may result in pressure on the aorta and vena cava which in turn may cause a drop in blood pressure and thus potentially a reduction in blood flow to the uterus has been long postulated as a cause of unexplained stillbirth.

This observation however took into account that the fetus has the physiological ability to counteract such changes as a result of blood shunting and placental reserve thus making this ‘cause’ unlikely.

To return to the reported study - there are a number of problems with this study which require further clarification before it can even be considered as a possible cause of stillbirth which in turn will require a solution if it is found to be valid.

The incidence of stillbirth in late pregnancy is of the order of 1-2 per 1,000 pregnancies of which approximately 30% are unexplained and thus to demonstrate an association with the sleeping position would require a study of several thousand normal pregnancies and stillbirths.

This study selectively examined a small group of only 295 pregnancies in which there were 105 stillbirths with the remaining pregnancies being used as a control group and it is with these small numbers that the observation was made that there was a 6 times increased chance of stillbirth in those women who slept on their backs.

The problem with releasing the results of an inadequately powered retrospective observational study is that it engenders unnecessary anxiety in those women who are currently pregnant and it may also generate unwarranted guilt to that very small group of women who have experienced the tragedy and heartache of losing a baby late in pregnancy.

To reinforce our point of view the ‘plain English’ conclusions of the study were reported thus:

  • Women who sleep on their backs six times more likely to have stillbirth
  • May reduce blood flow through a major vein that supplies blood to the womb
  • But researchers stress no definitive link established!

So what should pregnant patients do now that this yet another anxiety- provoking statement has been made?

Be reassured that previous studies have shown that more than 75% of pregnant women sleep mostly on their left side instinctively and that the remainder toss and turn so much during the night that it is often impossible to know in which position they finally fall asleep!
If there is a reduction/alteration in the frequency of fetal movements late in pregnancy then this is worth a chat with your midwife or obstetrician who may decide to perform a reassuring fetal monitoring test.

To turn to matters more specific to Women’s Health Specialists, there has been considerable activity since our last newsletter with Professor Svigos participating in the first of a number of intended Master Class Vaginal Birth ‘hands on’ workshops around Australia in which he, with colleagues Dr Henry Murray and Professor Stephen Robson, will be promoting and demonstrating the vaginal delivery of twins, breech and rotational forceps delivery to senior trainees and newly graduated obstetricians in order that they might be able to provide additional mode of delivery options for pregnant women. The classes thus far have been booked out with a long waiting list for obstetricians wishing to participate.

Professor Svigos during October and November is supervising the second group of Maternal Fetal Medicine trainees from Indonesia who are doing an annual 2 month rotation through the Women’s and Children’s Hospital and the Lyell McEwin Hospital as part of their two year subspecialty training program which he has designed for the Indonesian College of Obstetrics ad Gynecology and for which he has arranged sponsorship by the University of Adelaide and financial assistance from AusAID.

As part of this commitment Professor Svigos will be away from the practice 8th May – 18th May 2013 when he will be travelling to Indonesia to convene a third Combined Clinical Meeting between the staff of the Women’s and Children’s Hospital and Sanglah Hospital.

He will also be travelling to the United Kingdom for two weeks in July 2013 for a study and lecturing tour.

He will not be accepting obstetric bookings for women who may be delivering at these times to avoid any disappointment and not to overload Dr Basil Antonas and Dr Darren Roberts who will be covering the practice in his absence.

Inevitably when bookings are declined then there is conjecture that Professor Svigos is retiring or ‘giving up’ obstetrics – he wishes to reassure you that nothing could be further from the truth and that you will have to put up with him for much longer!

Meantime midwives Jane and Deanna and the WHS administrative staff of Maria, Carol and Shirina continue to remain busy providing the necessary support for the practice and just as importantly remaining current and in tune with your needs.

In anticipation, a Merry Christmas and a Happy New Year (including Chinese New Year) to you all along with our compliments and respects for Ramadan and Rosh Hashanah and equivalent religious and traditional celebrations earlier this year and early next year.

Past Newsletters
April 2011
September 2011
March 2012
November 2012
June 2013
December 2013
September 2014