I've had a reply from Zita West; all in all looks like it's fine to be taking their fish supplements for ttc / pregnancy:
Thank you for your email.
I can fully understand why you were alarmed by the advice found on the NHS Choices site, which I have to say is rather misleading and, as we would see it anyway, unhelpful.
As you may know, there have been concerns about some pregnant women who may have very high intakes of Vitamin A in pregnancy, mainly as a result of their consumption of large and regular amounts of liver during pregnancy. Liver contains high amounts of the animal form of Vitamin A, which is known as Retinol. Some research has suggested that there may be an association between high levels of Retinol intake and a higher risk of birth defects. As a result, health professionals, sensibly, tend to steer women away from both foods and supplements containing it. We do the same here at our clinic.
Vital DHA, however, has been specifically developed for use during preconception, pregnancy and breast-feeding. Most particularly, to help those women, of whom there are many, whose regular diets do not contain a regular intake of Essential Fatty Acids (EFA's), such as oily fish, which all health experts recognise as important both prior to and during pregnancy. The oils used in Vital DHA are all derived from the body of oily fishes, not the liver. Retinol is not present in any measurable quantity in either of the two base oils we use to make the product and, as such, none of the concerns mentioned earlier apply. All of the oils used in Vital DHA are also molecularly distilled during the manufacturing process to test for the absence of all known contaminants. This removes the concern that many women also understandably have about the risk of exposing themselves, and their babies, to high levels of mercury from eating regular portions of the larger fresh oily fish, such as tuna, swordfish and shark.
Though it is, of course, correct to say that there is not enough medical evidence to completely support the contention that fish oil supplements can improve a baby's cognitive development, it would be inappropriate, in our view, to completely dismiss the evidence that does exist of its potential benefits in this area, just as it would be to overlook the other benefits that research has suggested may result from building a good maternal store of Essential Fatty Acids (EFA's) such as DHA and EPA during pregnancy. Zita has long been a passionate supporter of the value of DHA supplementation throughout the reproductive cycle, and that remains the case.
Whether you would like to continue taking Vital DHA must, of course, be a personal choice on your part. Should you still feel rather unnerved by your experience, we would fully understand, but please do be reassured that there is no reason to be concerned about the product's safety.
If you do, in the end, decide to stop taking the product, do please make sure you get back in touch as I would like to arrange for you to be refunded for the cost of the Vital DHA you have purchased. We wouldn't want you to have to pay for something with which you have not been entirely satisfied.
I hope this helps.
Yours sincerely
(name deleted)
ZITA WEST PRODUCTS LTD