DHA supplementation to improve maternal, foetal and infant outcomes: is the current recommendation appropriate for women with very low intake and status?
It is widely acknowledged that there is an enhanced demand for docosahexaenoic acid (DHA) in pregnancy and lactation. Moreover, DHA is one of the most important limiting nutrients. The conversion of alpha-linolenic acid (ALA), which is a minor constituent of most vegetable oils except linseed, soybean and rapeseed, to DHA is very low and variable, although women of child-bearing age are thought to have enhanced synthetic ability.
Preformed DHA is found in seafood in significant amounts . However, except in countries where fish and seafood intake remains high (ie Japan and Korea), the consumption of these foods by most individuals is sub-optimal even in wealthy nations. Consequently, it has been recommended by working groups that expectant and nursing mothers need to consume 300 milligrams per day (mg/d) and at least 200 mg/d of DHA. These recommended values (which are based on breast milk and maternal, neonatal and infant blood DHA data from supplemented and unsupplemented women mainly from developed countries) are essentially guesstimates. In our study of a cohort of unsupplemented pregnant British women, the level of DHA in maternal and cord plasma choline phosphoglycerides and mature milk total lipid were 5.2, 6.6 and 0.4%. The corresponding values in our Sudanese study were 2.3, 3.34 and 0.06%. The data clearly show that the level of DHA in plasma of the Sudanese mothers and neonates was lower by about 50% and in breast milk by 85%. The question is whether supplementation of the Sudanese mothers with 200 or even 300 mg/d would increase maternal and neonate plasma and breast milk DHA more than two-fold to broadly match the levels of the unsupplemented British women.
The aims are to:
- determine the amount of docosahexaenoic acid (DHA) required to increase the status of the nutrient in healthy Sudanese expectant and nursing mothers to levels commonly observed in supplemented and unsupplemented British women
- investigate whether antenatal supplementation with DHA is sufficient to raise breast milk concentration to levels of women who received the supplement during antenatal and postnatal periods
- assess the effect of DHA supplementation of Sudanese pregnant women on foetal growth, premature delivery, gestation week at delivery, birth weight, head circumference and length
The study is being carried out in collaboration with the University of Khartoum Hospital, Khartoum, Sudan (Professor Mustafa Idrin Elbashir).
The study is registered with Current Controlled Trials (registration number ISRCTN03848493).