COGI 2018: 5 key messages

COGI is over for another year. Now we can take time to digest the information from the inspiring and thought-provoking sessions and ask ourselves: ‘what have we learnt?’

In this special edition blog we look back at five key messages and highlights from the three days.

 

1.       Time to consider HRT for primary CHD?

Research suggests that estrogen has a clear biological effect on the cardiovascular system, demonstrating beneficial effects on some of the key risk factors of Cardiovascular Heart Disease (CHD). While there is a lack of definitive evidence supporting HRT as a prevention for postmenopausal CHD, there are a growing number of epidemiological and observational studies supporting its use. In these studies, timing was shown to be a key factor with HRT demonstrating no benefit in older women. However, although there was no benefit there was also no evidence of harm.

 

2.       The role of epigenetics in long term health

Specific epigenetic input during development can produce a lasting difference in phenotype, meaning fetal programming, metabolic endocrine disruption and structural change in organs can all significantly affect the birth of a child.

For example, Caesarean Sections are linked to increases in neonatal morbidity, auto-immune diseases and metabolic disease in the offspring. Maternal obesity and smoking are also shown to be associated with long term negative outcomes for the child. In fact, research suggests that these negative effects may even cross generations.

 

3.       Fertility may be able to be preserved in women with POI

Primary ovarian insufficiency (POI) affects 1 in 100 women at the age of 40. In order to plan the most effective fertility preservation treatment, it is crucial to predict as much as possible whether POI may be imminent. While this is not simple, the condition is hereditary therefore assessing family history may help to provide important insight. Additionally, more research is taking place into the genetic basis of POI, with some evidence suggesting that reproductive health and success may be a marker for identifying POI and health outcomes later in life.  

There are many more options available for treating imminent POI than confirmed POI, including vitrification of oocytes or embryos following ovarian stimulation, freezing of ovarian tissue or a combination of the two. When treating confirmed POI, the options are more complex. While a small number of sufferers may go on to experience a spontaneous pregnancy, researchers are now considering a new technique: in vitro follicle activation (IVA). However, refinement and improvement of the technique is needed for it to lead to an effective strategy for these patients.

  

4.       The freezing debate is definitely not over!

The debate on whether freezing oocytes for non-medicinal reasons is truly beneficial contined at COGI. Speakers argued that social freezing could be seen as a purely commercial enterprise with advertising often aggressive and marred with misinformation. In fact, only 12% women actually return to the clinic and there is a far from certain chance of success.

However, freezing was shown to provide effective results in younger women seeing fertility preservation. In addition, some studies have demonstrated that freezing may be able to reduce risk of OHSS and be beneficial for groups of high responders.

 

5.       ART may be driving rates of pre-term birth

ART is associated with increased incidence of multiple pregnancy. Multiple pregnancy in turn is related with higher risk of pre-term birth and Cerebral Palsy. Using real world data we were shown that incidence of twins born at <32 weeks increased 27-fold from 1987 to 2010, with ART suggested as a main driver.

Why we should consider epigenetic factors for IVF

 Research has demonstrated that children born through assisted reproductive technology (ART) are at a higher risk of preterm birth and associated morbidity.[1] So, why is? Well, the cause is likely to be multifactorial. There is the potential that IVF techniques could result in obstetric complications that negatively impact the child, or that ovarian stimulation may negatively impact placental development.[1] However, growing evidence suggests that parental characteristics play a crucial role.  

The opening night of the 26th Annual COGI Conference kicked off with a thought provoking exploration of this fascinating area of epigenetics, considering how parental factors can affect the health of an IVF child.  Epigenetics, the speakers explained, is inherently linked to the concept of developmental plasticity. Specific input during development can produce a lasting difference in phenotype.[2] As such, factors including fetal programming, metabolic endocrine disruption and structural change in organs can all significantly affect the birth of the child.

Effectively understanding how parental factors may affect future health outcomes could help us in the drive for increased precision medicine, where we can adapt specific treatments based on individual factors.

 

Caesarean Sections

 

Prof. Giancarlo Di Rienzo explained that IVF is associated with an increased use of Caesarean Section (CS) during birth. He showed that CS is in turn linked to increases in risk of:

-          Neonatal morbidity

-          Auto-immune diseases in the offspring

-          Metabolic disease in the offspring

 

Maternal Obesity and Smoking

 

Maternal obesity was highlighted as an important factor leading to higher risk of pre-term birth. Similarly, maternal smoking was shown to cause significant epigenetic changes. Interestingly, not only does smoking negatively affect the mother and the unborn child, but if the child is a female the smoke could also affect her reproductive cells. Therefore, these epigenetic changes could result in transgenerational negative effects. Indeed, Prof. Rienzo explained how increased risk of both pre-term birth and small for gestational age (SGA) infants has been shown to span multiple generations.

In his presentation, Prof. Nick Macklon also reiterated the role that diet and nutrition has in affecting epigenetic change.  

 

Could a Mediterranean Diet help?

 

Prof. Macklon explained that a Mediterranean diet is often recommended to women preparing for IVF. But is there really a benefit? To answer this question, he shared data assessing whether the diet has any significant positive impact on embryo quality and overall IVF success rate.

While there was some cohort evidence that the Mediterranean diet positively related to clinical pregnancy, Prof. Macklon explained that we must consider the important confounding factors including microbiome and genetics. He demonstrated that the positive impact of the diet, along with other advertised nutritionals on IVF outcomes is very slight, however this may have a greater cumulative effect over time.


Sources:

[1] A. Pinborg, U.B. Wennerholm, L.B. Romundstad, et al; Why do singletons conceived after assisted reproduction technology have adverse perinatal outcome? Systematic review and meta-analysis, Human Reproduction Update, Volume 19, Issue 2, 1 March 2013, Pages 87–104, https://doi.org/10.1093/humupd/dms044

[2] Nettle D, Bateson M. Adaptive developmental plasticity: what is it, how can we recognize it and when can it evolve?. Proc Biol Sci. 2015;282(1812):20151005.