<![CDATA[David Moore]]> http://drdavidmoore.com.au/ David Moore http://drdavidmoore.com.au/ http://drdavidmoore.com.au/ox/webcore/attachments/24286/webavatar.jpg?width=200&height=200 http://www.rssboard.org/rss-specification <![CDATA[Vitamin B3 and miscarriage]]> Vitamin B3 and miscarriage

This week, media outlets widely reported findings of an Australian study linking vitamin B3 to birth defects and miscarriages.  The study, published in the New England Journal of Medicine, was undertaken by an Australian research team headed by Professor Sally Dunwoodie.  The study findings have even been compared to the discovery of the link between folate and neural tubes defects such as spina bifida.

Unfortunately, though perhaps not surprisingly, media enthusiasm has allowed a good headline to get in the way of responsible journalism.  While the discovery of an association between vitamin B3 and birth defects (in mice) is interesting, important, and creates many questions for further research, it is a far, far cry from "preventing millions of women from suffering miscarriage".  

In a nutshell, the researchers of this study:

  • Tried to identify random genes that might be associated with the occurrence of multiple congenital abnormalities (that is, more than one birth defect occurring in the same person, suggesting something more than just random chance at work).
  • Found a couple of possible genes, among four families that included such individuals.
  • Determined that these genes were associated with NAD metabolism - mutations in these genes meant less NAD produced.
  • Created "knockout" mice (that is, mice that were genetically engineered to make zero NAD by completely removing all function of these genes - as opposed to these families, that had the genes, but some mutation in them that reduced their function).  That is to say, they created mice with significantly warped metabolisms.
  • Determined that these mice had babies with lots of congenital abnormalities (and early abortions – probably related to the lethality of multiple congenital abnormalities).
  • Acknowledged that NAD is synthesised using ether niacin (B3) or tryptophan (found in cheese).
  • Fed the mummy mice niacin and fixed the problem (which they created….)
  • Concluded that:
    • NAD is important to embryogenesis (like many other things….) -- this seems reasonable. 
    • Removing it – entirely – creates problems, in a mouse model at least. -- interesting. 
    • Removing it and replacing it prevents these problems. -- also interesting, perhaps not surprising given the first two points.
    • Theorised that niacin supplementation may be useful in these families with recognised gene mutations affecting NAD pathways-- MAYBE, but remains to be answered.

Importantly (and curiously left out by the media):

  • They didn’t actually conclude (nor should they), that niacin supplementation reduces birth defects in “normal” families.
  • NOWHERE in their study is the word “miscarriage” or phrase “first trimester loss” used (even though the entire media reports focus on B3 reducing miscarriage).
  • There are no trials (“intervention trials”) looking at the effect of NAD/niacin/B3 on low-risk women (or low-risk/non-mutant mice, for that matter).
  • Likewise, there are no intervention trials looking at supplementation in HIGH risk women, such as in these families.
  • There is NO safety data about high-dose niacin supplementation

The assumption is that something occurring naturally can’t be bad, BUT the entire HRT fiasco came from initial studies suggesting all women should take oestrogen because it prevents heart disease, and women with early menopause have more heart disease, so extra oestrogen must be good.  But women with extra oestrogen just turned out to have more strokes, more clots (and… MORE heart disease!) – the painful lesson from the HRT trials is that jumping in early, on the first promise of something useful, is not without risk. 

After much pain, a few law suits, and many more trials, we eventually settled on “HRT benefits may outweigh risks, in some women, sometimesmaybe”.

The unfortunate but inevitable consequence of over-enthusiastic journalism that reports gross extrapolations of animal studies is that women are offered premature - and currently unfounded - hope of a treatment that is not only unproven, but also untested.  With headlines like these, the only winners are manufacturers of Vitamin B3 supplements.  

Nevertheless, let's look forward to the follow-up study findings from this Australian team of researchers!

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http://drdavidmoore.com.au/vitamin-b3-and-miscarriage http://drdavidmoore.com.au/vitamin-b3-and-miscarriage Sun, 13 Aug 2017 20:04:37 +1000
<![CDATA[Important information for Medibank Private members]]> Important information for Medibank Private members

Medibank Private is taking action to increase shareholder profits by drastically limiting the value of their insurance product for their members.  These measures are touted at improving healthcare outcomes but, in truth, are without any evidence basis and are completely unvalidated.  Despite loyal premium payments, Medibank members are at risk of finding themselves completely without insurance coverage, at no fault of their own, their doctor, or their chosen Private Hospital.  This is the thin end of a tactical wedge being aimed between patients and their healthcare choices;  the endpoint would likely be similar to overseas models of Private Healthcare, where insurers dictate from which doctors and hospitals patients may receive care, as determined by the insurers' commercial interests.

Read what the Australian Private Hospitals Association has to say about the move here.  Remember, all Australians are entitled to switch Health Funds at any time without penalty.

Vote with your feet.

 

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http://drdavidmoore.com.au/important-information-for-patients-insured-with-medibank-private http://drdavidmoore.com.au/important-information-for-patients-insured-with-medibank-private Sat, 22 Aug 2015 16:50:00 +1000
<![CDATA[Influenza vaccination in pregnancy - proven efficacy]]> Influenza vaccination in pregnancy - proven efficacy

Every now and then, a "landmark paper" - a paper of great clinical significance - comes along.  I believe we've seen one this week!

A paper published this week in the New England Journal of Medicine is the first to show, through the power of a randomised control trial (or RCT, the most rigorous way of determining whether a cause-effect relationship exists between a treatment and an outcome), that influenza vaccination during pregnancy protects mothers and babies.

The researchers enrolled over 2300 pregnant women and randomised them to receive the current influenza vaccination or placebo (saline), between 20 and 36 weeks of pregnancy.  From the date of vaccination, women were contacted weekly to detect symptoms of a "flu-like illness" and, if reported, they were tested specifically for influenza through highly-specific PCR testing.  Women were followed up until about 6 months after birth, and their babies were followed up from birth to about 6 months of age.  

As well as showing that both mothers and babies had "boosted" immunity (through testing the levels of protective antibodies in their blood), the researchers found an almost 50% reduction in PCR-proven influenza infection in both mums and babies.

This is of major public health importance for two reasons: firstly, pregnant women are recognised as being the adult group at highest-risk of severe influenza illness during epidemics and pandemics, even in high-income countries like Australia.  Secondly, young infants are particularly susceptible to (and may be severely affected by) influenza illness, and no vaccine is currently licensed to protect this age group.

Influenza vaccination is already recommended (and PBS subsidised) for pregnant women in Australia.  It does not contain live virus, and the composition of the vaccine changes every year, to keep up with the current seasonal influenza virus strains.  This study provides final validation that influenza vaccination in pregnancy is a good idea, and the researchers are to be congratulated.

Now, go and get your vaccination!

 

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http://drdavidmoore.com.au/influenza-vaccination-in-pregnancy-proven-efficacy http://drdavidmoore.com.au/influenza-vaccination-in-pregnancy-proven-efficacy Thu, 11 Sep 2014 00:21:38 +1000
<![CDATA[Endometriosis]]> Endometriosis

 

What is endometriosis?

Endometriosis is a condition that only affects women.  It occurs when tissue that normally grows within a woman’s uterus (her womb) – called endometrial tissue – grows elsewhere in the body.  During a woman’s “period”, or menstruation, the endometrial tissue in the uterus breaks down and bleeds.  However, the endometriosis lesions located elsewhere in the body also break down, causing bleeding and inflammation; this is what produces the pain of endometriosis.

Sites commonly affected by endometriosis include:

  • The ovaries or Fallopian tubes

  • The bladder or bowel, including the appendix

  • The outside surface of the uterus

  • Ligaments in the pelvis or the side walls of the pelvis

  • Occasionally, the cervix or vagina may be affected

 

Endometriosis is not life threatening but can cause significant pain, and difficulty falling pregnant.

 

What are risk factors for developing endometriosis?

Around 10% of women may suffer from endometriosis.  Some risk factors include:

  • Close family history (mother or sister with endometriosis)

  • Short duration between periods

  • Young age at first period

  • A lean build (tall, slim)

  • Not having children

 

How do I know if I have endometriosis?

Some women do not have symptoms of endometriosis, but may have trouble falling pregnant, or have ovarian endometriomas found when medical imaging tests are done for other reasons.  Many women, however, experience lower abdominal discomfort or pain.  Symptoms commonly experienced may include:

  • Painful periods

  • Pain during sex

  • Pain with passing urine or having a bowel motion, especially around the time of a period

Often, symptoms only occur, or are worse, around the time of the menstrual period.  However, they may be persistent at any time during a menstrual cycle.  Additionally, many women experience similar symptoms without having endometriosis.

 

 

What will my doctor do if endometriosis is suspected?

There is no simple test to prove or disprove the presence of endometriosis.  Often a pelvic ultrasound may be arranged to look for some causes of pelvic pain and, sometimes, ovarian endometriomas may be revealed.  In most cases, however, a pelvic ultrasound is normal despite the presence of endometriosis.  If your doctor suspects endometriosis, he or she may discuss presumptively treating you on the basis of your symptoms, or refer you to a specialist gynaecologist for further investigation and treatment.  Ultimately, endometriosis can only be diagnosed by direct visualisation and biopsy of lesions at surgery.

 

How is endometriosis treated, and can it be “cured”?

Endometriosis can be treated with medications, surgery, or both.  The type of treatment chosen depends on your symptoms and whether or not you’re trying to fall pregnant.  Medications may include:

  • Pain medications: often paracetamol or anti-inflammatories

  • The contraceptive pill

  • Other hormonal therapies

Surgical treatment of endometriosis can usually be performed through small “keyhole” incisions, and can significantly improve symptoms in up to 80% of women.  Surgery may be chosen instead of medical therapy, where medical therapy has failed to adequately improve symptoms, or to improve fertility where pregnancy is desired.  Medical therapies do not improve fertility.

In some women, endometriosis can resolve without treatment.  In women who receive treatment, up to 50% may experience recurrence of endometriosis at a later stage.

 

Will I be able to have a baby if I have endometriosis?

Endometriosis may reduce the chance of falling pregnant each month, but it does not completely prevent it.  Around 30-50% of women with endometriosis will experience infertility.  As such, surgical treatment is not necessary just to “protect” your fertility, if you are not currently trying to have a baby.  If endometriosis has been found during investigation of infertility, however, there is research evidence that your chances of falling pregnant are improved after surgical treatment.  In some cases, natural pregnancy is still delayed after treatment, and assisted fertility treatments (such as in vitro fertilisation, IVF) may be necessary.

 

Where can I get more information?

Your general practitioner may be able to provide you with more information, or may refer you to a specialist for further advice and management.

Other resources:

 

The content and information contained on this website is intended to be of a general nature only and is not intended to, nor does it constitute, medical advice.  It does not take into account your particular circumstances or needs.  No doctor/patient relationship is implied or formed. The accuracy, completeness, adequacy, or currency of the content is not warranted or guaranteed. Use of information on this website, or materials linked from the website, is at the user's own risk.  The contents of the site, such as text, graphics, images and other materials are for informational purposes only. The content is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Users should always seek the advice of their qualified health providers with any questions regarding a medical condition. Users should never disregard professional medical advice or delay in seeking it because of something on this website.  Specific recommendations can only be made after direct individual consultation.  The website does not recommend or endorse any specific tests, products, procedures, or other information that might be mentioned on the website.

 

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http://drdavidmoore.com.au/endometriosis http://drdavidmoore.com.au/endometriosis Tue, 19 Aug 2014 23:54:37 +1000
<![CDATA[Epidurals and postpartum depression]]> Epidurals and postpartum depression

A recent study has suggested an association between epidural use in labour and a reduced rate of postpartum depression.  Hmmm...seems a little too good to be true...

The research paper, published here in Anesthesia & Analgesia, found that women who used epidural analgesia in labour had a 14% risk of postpartum depression, compared to nearly 35% of women who did not have an epidural.  Sounds great!  While I'm all in favour of women accessing highly effective pain relief in labour, this headline prompted me to read a little deeper...

The study was a prospective observational study, which means that confounding factors (other aspects that may contribute to the study findings) cannot be accounted for entirely (best achieved through a randomised controlled trial).  Ok, not a biggie; but the authors rightfully describe their findings as an association, which doesn't infer a causal link between the exposure (epidurals) and the outcome (postpartum depression).  This is an important limitation of all observational studies, which is generally overlooked in the media.

Additionally, the overall rates of postpartum depression described in the study are alarmingly high - around 25%.  Partly this is because the authors defined postpartum depression according to a score on the Edinburgh Postnatal Depression Scale (EPDS).  While the EPDS is a useful tool, it is a self-reported questionnaire designed to screen women for symptoms of emotional distress during or after pregnancy, and reflects the woman's experience over the preceding seven days.  While it is very helpful in identifying women at risk, it is not equivalent to a diagnosis of clinical depression per se.

Finally, the authors suggest a possible biological link between pain, post-traumatic stress-type symptoms, and postnatal depression, citing previous studies that associate pain and depression.  However, women in this study who chose not to have an epidural, received no other form of pain relief, as "other forms of analgesia are not available at our hospital".  This is unlike any hospital I've ever worked in, and makes no sense; moreover, it limits the external validity, or "generalisability" of the study (medical speak for how well we can expect study findings in a particular population to apply to any other population - i.e. our patients).

So, overall, an interesting study that presents an intriguing association between epidural use and a (thankfully) positive birth outcome.  But these findings must always be interpreted with measured caution and, hopefully, responsible journalism will prevail over attention-grabbing headlines that make sweeping statements that may unduly influence women's birth choices.  

 

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http://drdavidmoore.com.au/epidurals-and-postpartum-depression http://drdavidmoore.com.au/epidurals-and-postpartum-depression Wed, 30 Jul 2014 23:35:13 +1000
<![CDATA[More research to support whooping cough vaccination during pregnancy]]> More research to support whooping cough vaccination during pregnancy

Whooping cough, also called the 100 day cough, is an illness cause by the bacterium Bordetella pertussis.  While often causing an irritating cough in adults, pertussis can be life-threatening in children, especially newborn infants.  In fact, over 90% of deaths from pertussis infection occur in babies under two months of age.  Pertussis vaccination forms part of the Australian Immunisation Schedule, and begins in children at two months of age.  Unfortunately, therefore, children cannot be vaccinated during the highest-risk period of their lives.  Immunisation does not provide lifelong immunity and, until recently, pertussis vaccine boosters were recommended for dads-to-be and new mums, in attempt to reduce the likelihood of their new baby being exposed to parents  with active pertussis infection.

The idea of vaccinating pregnant women has been around for a while, with the rationale that maternal antibodies will pass through the placenta, giving baby "passive immunity" against the infection at birth and in the newborn period.  Additionally, the safety of this vaccine is well-established (it is comprised of proteins only; it is not a "live" vaccine).  However, this concept has not been readily proven, as "protective levels" of antibody in baby's blood have not been accurately set.  Furthermore, there has also been concern that such maternal antibodies may dampen the baby's immune response to their own childhood vaccinations, lessening the protective effect of the vaccine schedule.

A research paper published this month in JAMA has provided further insights into the possible benefits of vaccinating expectant mothers during each pregnancy.  These researchers randomised women to pertussis vaccination during pregnancy, or vaccination after birth.  Most of the mothers vaccinated after birth had received vaccination at some point previously during their lives.  They measured levels of protective antibodies in mothers near delivery, and in children at birth, two months of age, and after completion of their routine childhood pertussis vaccination program.  Reassuringly, they found that vaccination during pregnancy did not dampen the children's response to routine childhood vaccination.  Additionally, they confirmed that levels of protective antibodies were significantly higher (4-5 fold) in children of mothers vaccinated during pregnancy.  Although this study was not powered to prove a reduction in newborn pertussis infection rates (this would need an enormous study), and the protective threshold of antibody levels is not known, this research adds strength to the argument for vaccination of all mothers during each pregnancy, to maximise the levels of protective antibodies present during their babies' most vulnerable time for infection.

 

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http://drdavidmoore.com.au/more-research-to-support-whooping-cough-vaccination-during-pregnancy http://drdavidmoore.com.au/more-research-to-support-whooping-cough-vaccination-during-pregnancy Mon, 19 May 2014 23:38:33 +1000
<![CDATA[Are babies who are "turned" by ECV still more likely to be born by caesarean section?]]> Are babies who are "turned" by ECV still more likely to be born by caesarean section?

...a little, yes.

A new systematic review published ahead of print in Obstetrics & Gynaecology this week has confirmed that the rate of subsequent caesarean section is higher in women who have had a baby successfully turned from a breech to a cephalic presentation by ECV.  In this study, the rate of caesarean section after successful ECV was 21%, which compares to an intrapartum caesarean section rate for women with cephalic-presenting babies of around 12-15%.  Nevertheless, ECV remains a safe, simple, and scientifically valid method for women wishing to avoid caesarean section; the authors found that three women need to undergo an attempted ECV to prevent one caesarean section.  In medicine this is called the "number needed to treat", or NNT.  The lower the NNT, the more efficient the treatment is, and a NNT of three is excellent. 

 

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http://drdavidmoore.com.au/are-babies-who-are-turned-by-ecv-still-more-likely-to-be-born-by-caesarean-section http://drdavidmoore.com.au/are-babies-who-are-turned-by-ecv-still-more-likely-to-be-born-by-caesarean-section Fri, 16 May 2014 00:09:04 +1000
<![CDATA[Does low dose aspirin reduce the risk of miscarriage?]]> Does low dose aspirin reduce the risk of miscarriage?

According to an RCT published in The Lancet this week - maybe...

Low-dose (75-100mg) daily aspirin ("LDA"), commenced before 16 weeks, has been shown in high-powered studies to reduce the risk of some adverse pregnancy outcomes such as pre-eclampsia, fetal growth restriction, and preterm birth.  The effect is strongest in high-risk women (viz. women who have suffered such adverse events in previous pregnancies; see Villa et al, BJOG 2013 and Roberge et al Ultrasound O&G 2013).  As often happens in medicine, "indication creep" means that we become tempted to prescribe these proven therapies for indications in which they are unproven.  Recurrent miscarriage or recurrent pregnancy loss ("RPL", defined as three or more consecutive pregnancies ending in miscarriage before 20 weeks) causes immeasurable anguish to couples, and it is normal to seek out ways of mitigating against future pregnancy loss.  Interestingly, LDA coupled with low dose heparin has been shown to reduce the rate of subsequent miscarriage in women with RPL who also have antiphospholipid syndrome; whereas this recipe has no effect in women with RPL in the absence of antiphospholipid syndrome (Kaandorp et al Cochrane 2009).

The use of LDA in women without RPL (that is, one or two miscarriages only) has found mixed results with small, unpowered studies previously.  The authors of this most recent, large, placebo-controlled RCT (dubbed the "EAGeR study") sought to scrutinise this relationship more clearly.  They studied the effect of commencing such women on LDA before conception, and found no improvement in livebirth or miscarriage rates for women who had "one or two" previous miscarriages, and concluded that routine LDA should not be used in this group.  Interestingly, however, their data did reveal a statistically significant improvement in pregnancy and livebirth rates in a group of women who had one previous miscarriage, before 20 weeks, within the last year.  Hmm... tough to explain the mechanism there, and perhaps it's a statistical anomaly ("Lies, damned lies, and statistics"), but certainly that little chestnut requires more research.  Miscarriage has a very complex group of causes, and there's no biologically plausible way that aspirin would improve many of them (such as chromosomal problems).

So, bottom line, LDA shouldn't be used indiscriminately with the hope of improving livebirth rates - we have good evidence for particular populations of women who benefit, and quality evidence to refute benefit in other populations.  This study adds to this knowledge.  

PS- I often get raised eyebrows when discussing aspirin use in pregnancy ("isn't that harmful?") - there is extensive evidence for the safety of low-dose aspirin when suitably prescribed in pregnancy (James et al O&G Survey 2008).

 

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http://drdavidmoore.com.au/does-low-dose-aspirin-reduce-the-risk-of-miscarriage http://drdavidmoore.com.au/does-low-dose-aspirin-reduce-the-risk-of-miscarriage Thu, 3 Apr 2014 01:43:36 +1100
<![CDATA[Excisional procedures for CIN2-3 do not increase the risk of preterm birth.]]> Excisional procedures for CIN2-3 do not increase the risk of preterm birth.

Pre-cancerous lesions of the cervix (i.e. CIN2-3), detected by Pap smear screening and confirmed by colposcopy and biopsy, and frequently treated by an excisional procedure such as a LLETZ or LEEP.  In women who have not yet completed their childbearing, these procedures have been thought to increase the risk of preterm birth, and this is factored into decision-making when choosing active treatment (excision) versus a "wait and see" approach (conservative).  Some previous studies have suggested that the changes to cervix's microstructure due to the disease process itself, and not the treatment procedure, may be the real cause of this risk of preterm birth.  This week a large meta-analysis of available evidence has been published in the journal Obstetrics & Gynecology.  Comparing >6'500 women who underwent a LLETZ/LEEP to women who have not, they confirmed this procedure is associated with an increase in the risk of birth before 37 weeks by about 60% (or an absolute risk increase of 3%).  However, when comparing to women who underwent a LLETZ/LEEP to women known to have dysplasia but managed without surgery, there was no difference in the rates of birth before 37 weeks.  This is the strongest evidence to date to suggest that LLETZ procedures may not be an independent risk for preterm birth, and this information will no doubt alter how we counsel women when deciding their treatment options.  

*(Data excluded laser and cone biopsies)

Article available here.

 

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http://drdavidmoore.com.au/excisional-procedures-for-cin2-3-do-not-increase-the-risk-of-preterm-birth http://drdavidmoore.com.au/excisional-procedures-for-cin2-3-do-not-increase-the-risk-of-preterm-birth Wed, 2 Apr 2014 23:42:32 +1100
<![CDATA[Eating allergenic foods during pregnancy won't cause allergies in children]]> Eating allergenic foods during pregnancy won't cause allergies in children

Heard the old wives' tale about avoiding "allergy foods" in pregnancy, lest your child develop allergies? 

Well some more evidence to put that to rest: 
A cohort study in press has examined the association between mothers' intakes of common food allergens during pregnancy, with the rates of childhood asthma and allergy.   The researchers found NO evidence that avoiding food allergens results in a reduced risk of childhood allergy; in fact, a modest reduction was found in the odds of childhood asthma/allergies when mothers' diets were high in peanuts, milk, and wheat

So, bottom line, prospective parents do not need to worry about restricting their diets out of fear of causing allergies in their children.  

View abstract here

 

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http://drdavidmoore.com.au/eating-allergenic-foods-during-pregnancy-won-t-cause-allergies-in-children http://drdavidmoore.com.au/eating-allergenic-foods-during-pregnancy-won-t-cause-allergies-in-children Tue, 25 Mar 2014 01:41:39 +1100
<![CDATA[Screening tests in pregnancy]]> Screening tests in pregnancy

 

In this article:

Routine blood tests

Ultrasounds

Non-invasive prenatal testing for Down Syndrome (NIPT)

Screening for gestational diabetes

 

What are screening tests and why are they done?

Screening tests are tests that try to identify the presence of a problem or risk factor, in a person who does not show obvious signs of that problem (that is, they have no symptoms, or are "asymptomatic").  This means, by definition, screening tests are applied to healthy people with no symptoms of disease or problems.  Like any test in medicine, screening tests are not perfect, and the risk of an untrue result needs to weighed against the benefits of detecting the problem.  In essence, this means screening tests should be used only when detecting the problem will lead to a reasonable chance of improving the health or management of the screened person. 
 

What screening tests are done in pregnancy?

In pregnancy, several screening tests are recommended, and others are offered depending on your individual circumstances or previous history.  Generally speaking, these tests look for conditions that may alter the management of your pregnancy (e.g. anaemia, Rhesus-negative blood group, the presence of chronic infections, susceptibility to other infections).  

In the absence of specific conditions or complications, the Royal Australian and New Zealand College of Obstetricians and Gynaecologists recommends the following screening tests, either pre-pregnancy or when pregnancy is diagnosed:
 

  • Full blood count: this looks for low blood ("anaemia") and may suggest the underlying cause.  Sometimes further tests are required if significant anaemia is found.
  • Blood group and antibody screen: this is to determine you blood type (A, B, AB, or O) and, importantly, your Rhesus status (negative or positive).  The most common blood group is A-positive (type A, Rhesus-positive).  About 15% of women are Rhesus negative, and this may slightly alter their pregnancy management.  This test also looks for other "antibodies" which are occasionally of significance during a pregnancy.
  • Rubella immunity status: most women are immune to the Rubella (or German measles) virus, thanks to vaccination of school-aged children.  If you are non-immune, your doctor will talk to you about avoiding potential sources of infection during pregnancy, and you should have a vaccination shortly after baby is born (usually the next day).
  • Other serological tests: these generally test for the presence of syphilis, Hepatitis B and C viruses, and HIV.  Though uncommon, many women with these infections do not have risk factors in their history, and so routine screening is recommended.  Additionally, recognition, prompt treatment, and/or altering practices during birth, can significantly reduce the risks to baby during pregnancy and birth.
  • Urine test: this is a screening test for urinary infection, that may be asymptomatic in early pregnancy.  Importantly, the presence of bacteria in the urinary system (bacteruria), when untreated, is associated with and increased risk of preterm birth owing to complicated infection of the urinary tract.
  • Pap smear: if your next Pap smear would fall due during your pregnancy, you would be recommended to have a Pap smear taken at your first antenatal visit.  There is no evidence that a Pap smear is harmful in pregnancy, although you should tell your doctor if you may be pregnant, as it may alter their technique for test collection.
     

Other screening tests that may be suggested include:

  • Varicella (chickenpox) immunity: if you do not have a clear history of chickenpox, this test may be used to work out if you are immune or not.  Knowing your immune status can be helpful if you are exposed to chickenpox during pregnancy.  A known history of chickenpox, even as a child, is a very reliable indicator of immunity.
  • Thyroid function: routine screening of thyroid function remains an area of controversy and research.  However, depending on your particular personal or family history, you may be screened for thyroid disorders.
  • Vitamin D: vitamin D plays an important role in bone health, and the prevalence of vitamin D deficiency appears to be increasing.  Although routine vitamin D supplementation in pregnancy may be recommended, sometimes your level will be checked beforehand, especially if you are at risk of deficiency (e.g. darker-skinned women).
  • Toxoplasmosis and cytomegalovirus (CMV) immunity: routine testing for evidence of previous exposure to these infections is controversial.  Partly because there is no effective vaccine at present, there is no effective way of reducing transmission to a fetus from the mother, and also because a blood test demonstrating immunity does not eliminate the risk of re-infection during pregnancy.  These infections are very common (usually causing a flu-like illness in children or adults) and most people are already immune.  If you are at particular risk of these infection (for instance, you work in Child Care), it may be beneficial to know your immune status; however, the general rule of good hygiene and careful food preparation, and avoiding close contact with people who are ill with the "flu", is recommended regardless.

 

Screening ultrasounds

Unlike X-rays and CT scans, ultrasounds use non-ionising energy to produce clinical images, and are considered very safe in pregnancy.  The following outlines some of the routine ultrasound scans most women have during their pregnancy:

  1. Dating or "viability" scan: this is best requested between 7 and 10 weeks after a missed period.  It provides reassurance that baby is growing well, and serves to confirm your estimated due date.  It is highly accurate in estimating the current duration of your pregnancy to within 4 days.  If done earlier than 7 weeks, sometimes an internal ultrasound (where the probe is sheathed and placed inside your vagina) is required to see the baby. 
  2. Nuchal translucency or "12 week" scan: this scan is done as part of Combine First Trimester Screening (CFTS) for certain chromosome disorders, such as Down Syndrome.  The scan is performed between 11 and 14 weeks (usually around 12-13 weeks), and also required a blood test to complete the risk assessment.  The result is not a "yes" or "no" for Down Syndrome; rather, it gives a personalised assessment of the risk of Down Syndrome in a specific woman in a specific pregnancy.  A scan at this stage is also highly accurate for estimating your due date (error range of 4 days), and serves as a reassuring assessment of baby's development to date.  Thus, even couples not wishing to undergo risk assessment for Down Syndrome may still have the ultrasound done, without the blood test or specific measurements required for CFTS.
  3. Morphology or "19 weeks" scan: during this scan a complete "anatomical survey" of baby is taken, to rule out structural development problems, such as congenital heart defects.  It is usually performed between 18 and 24 weeks.  Importantly, while a normal scan is very reassuring, not all structural defects can be identified during this scan.  This scan also determines the position of the developing placenta, to make sure it is clear of the birth canal.

Depending on a woman's history and current pregnancy, additional ultrasounds may be required.  For instance, if the placenta is thought to be low (too close to the cervix) at the morphology scan, a later scan (around 32-34 weeks) will be ordered to ensure it has moved clear.  In the case of twin pregnancy, several more ultrasounds are required, every 2-4 weeks, to ensure both babies are growing well and without complications. 

 

Other screening tests:

Gestational diabetes screen

Gestational diabetes mellitus (or GDM) is a condition that develops in pregnancy, when the body is not able to make enough insulin to keep the mother's blood sugar levels in the normal range.  If untreated, it can result in complications such as blood pressure disorders and large babies, which increase the risk of difficult delivery.  GDM affects around 8% of pregnancies, and usually develops in the third trimester, and so a screening test is recommended at around 26-28 weeks.  If present, prompt treatment is needed to limit any risk of complications.  


36-week blood test

This is a simple blood test to rule out any late pregnancy anaemia, check your platelet count, and confirm the absence of troubling antibodies, if you are Rhesus-negative.


Non-invasive prenatal testing (NIPT)

NIPT is a relatively new technology that aims to accurately predict or exclude Down Syndrome and other chromosomal problems in baby, by detecting fragments of baby's DNA in the mother's bloodstream.  It simply involves a blood test from the mother, and so is "non-invasive" to the pregnancy itself.  As a screening test, it is the most powerful tool for excluding Down Syndrome.  Any positive result, however, still needs to be confirmed with a Diagnostic (or "invasive") test, such as amniocentesis.  At the moment, there is no Medicare rebate for this test, and generally costs the patient around $400-$500.  There are no Australian guidelines to guide the use of these tests, so it remains for your doctor to discuss the potential benefits of this test in your particular case. and help you decide if it is right for you.

 

David practices evidence-based medicine, and strives to ensure all conditions that may complicate a pregnancy are managed according to the best available medical literature and published guidelines.

 

The content and information contained on this website is intended to be of a general nature only and is not intended to, nor does it constitute, medical advice.  It does not take into account your particular circumstances or needs.  No doctor/patient relationship is implied or formed. The accuracy, completeness, adequacy, or currency of the content is not warranted or guaranteed. Use of information on this website, or materials linked from the website, is at the user's own risk.  The contents of the site, such as text, graphics, images and other materials are for informational purposes only. The content is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Users should always seek the advice of their qualified health providers with any questions regarding a medical condition. Users should never disregard professional medical advice or delay in seeking it because of something on this website.  Specific recommendations can only be made after direct individual consultation.  The website does not recommend or endorse any specific tests, products, procedures, or other information that might be mentioned on the website.

 

Read more...

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http://drdavidmoore.com.au/screening-tests-in-pregnancy http://drdavidmoore.com.au/screening-tests-in-pregnancy Tue, 27 Aug 2013 22:15:12 +1000
<![CDATA[Morning sickness]]> Morning sickness

 

 

What is morning sickness?

Morning sickness is the feeling of nausea (sometimes with vomiting) that many women get during their pregnancy.  Up to 9 in 10 women will experience morning sickness, and symptoms vary from mild and annoying, to severe - sometimes requiring admission to hospital.

The term "morning" is a bit of a misnomer - most women experience nausea all day long; though many women report vomiting only in the morning.  Most women develop symptoms within the first two months of pregnancy and, often, symptoms improve considerably after the first trimester (three months).  

It is unclear what causes morning sickness, although theories generally include high hormone levels such as beta-hCG (the "pregnancy hormone"), and alterations to stomach and intestinal motility (that is, the movement of food through the gut).  Morning sickness is more common in twin pregnancies (perhaps reflecting the higher hormone levels) and can be worsened by thyroid disorders.  Perhaps the only comfort to be found, in this sometimes debilitating condition, is that moderate-to-severe morning sickness appears to be associated with a lower risk of miscarriage.

 

What are the risks of morning sickness?

In the great majority of cases, morning sickness is an unpleasant nuisance, but poses no threat to the mother or her baby.  In severe cases, however (termed "hyperemesis gravidarum", or HG), a woman may become profoundly dehydrated and undernourished.  Babies generally tolerate poor maternal weight gain in early pregnancy, so problems with baby's growth is rarely seen, even in significant HG.  Mothers, on the other hand, may require admission to hospital where they can be rehydrated through a drip, while receiving medicines to reduce their symptoms enough for them to begin to tolerate a normal diet.

 

Vitamins and medicines for morning sickness

Several medicines are available to help you cope with symptoms of morning sickness, if needed.  These range from specific vitamins and other non-pharmaceuticals, to over-the-counter and prescription medications, such as:

  • Pyridoxine: vitamin B6, a non-drug treatment for nausea.
  • Ginger root: available in tablet form from your pharmacy.
  • Doxylamine succinate: an over-the-counter antihistamine with anti-nausea properties (safe in pregnancy).
  • Acid-reducing agents: such as antacid liquid or chewable tablets, or ranitidine, can help by reducing stomach acidity, which tends to worsens nausea. 
  • Prescription medications: commonly-prescribed examples are metoclopramide or, where symptoms are quite severe, prochlorperazine or ondansetron.  These should only be prescribed after a thorough medical evaluation by your GP or obstetrician

 

Tips for coping with morning sickness

  • Eat as soon as you feel hungry - even beforehand.
  • Frequent, small meals are better-tolerated than three large meals each day.
  • Brush your teeth immediately after eating.
  • Drink plenty of fluids - cold, clear, fizzy drinks are usually well-tolerated (e.g. ginger ale, lemonade).
  • Try to identify nausea triggers, so you can avoid them.  These are different for different women, but often include spicy foods, acidic juices, or foods with strong smells.  Keeping a symptom diary can help.
  • Take vitamins at nighttime with a small snack, rather than in the morning.
  • Avoid lying flat soon after eating.
  • Get plenty of fresh air.
  • Rest as much as possible.

 

Speak to your GP or make an appointment if you are finding difficulty in coping with morning sickness symptoms. 

 

The content and information contained on this website is intended to be of a general nature only and is not intended to, nor does it constitute, medical advice.  It does not take into account your particular circumstances or needs.  No doctor/patient relationship is implied or formed. The accuracy, completeness, adequacy, or currency of the content is not warranted or guaranteed. Use of information on this website, or materials linked from the website, is at the user's own risk.  The contents of the site, such as text, graphics, images and other materials are for informational purposes only. The content is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Users should always seek the advice of their qualified health providers with any questions regarding a medical condition. Users should never disregard professional medical advice or delay in seeking it because of something on this website.  Specific recommendations can only be made after direct individual consultation.  The website does not recommend or endorse any specific tests, products, procedures, or other information that might be mentioned on the website.

 

Read more...

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http://drdavidmoore.com.au/morning-sickness http://drdavidmoore.com.au/morning-sickness Tue, 27 Aug 2013 22:16:24 +1000