The regulation of reproductive function among lactating women

Lyliane Rosetta, Senior Researcher in Human Biology at Centre National de la Recherche Scientifique (CNRS), France.

A longitudinal survey was carried out in North East Bangladesh over 34 months to determine the duration of post-partum amenorrhea among chronically malnourished women.

150 Bangladeshi mothers were recruited during the week after delivery in 3 tea plantations. 40% of them were permanent tea garden workers and others were housewives or non-tea workers living in the same villages.

A permanent tea garden worker (credit: Lyliane Rosetta)

A protocol set up by the World Health Organization (WHO) for a multinational study on the relationship between infant feeding behavior and duration of postpartum amenorrhea was applied. Non invasive methods were used for quantitative measurements of biological characteristics, recording the pattern of breastfeeding and introduction of weaning food by questionnaires, and collecting regular urine samples for hormonal assays.

Non invasive methods were used to record biological characteristics (credit: Lyliane Rosetta)

Measuring the nutritional characteristics of mothers and infants was very important. This was done by assessing their food intake by weighing and investigating their total energy expenditure using heart rate monitoring and, for a subsample, the doubly labelled water method.

The doubly labelled water method was used to assess the total energy expenditure of a subset of women in the study (credit: Lyliane Rosetta).

The overall duration of post-partum amenorrhea in this sample is one of the longest registered in the last decade and is much longer than any of the values recorded by WHO in the multinational study. Two thirds of the sample was chronically energy deficient. Many of them had high level of  physical activity and limited food intake. The results suggest that energetics play a major role in the regulation of reproductive function.

This research was carried out in collaboration by L.Rosetta CNRS, France and CGN Mascie-Taylor, University of Cambridge UK, with grant from WHO, Geneva; and UNICEF, Dhaka, Bangladesh.

Further reading

ROSETTA, L., KURPAD, A., MASCIE-TAYLOR, C.G.N., & PS SHETTY (2005). Total energy expenditure (H2 18O), physical activity level, and milk output of lactating rural Bangladeshi tea workers and non-tea workers. European Journal of Clinical Nutrition, 59(5), 632-638.

 GHOSH R, MASCIE-TAYLOR, C.G.N. & ROSETTA, L. (2006) Longitudinal study of the frequency and duration of breastfeeding in rural Bangladeshi women. American Journal of  Human Biology, 18(5): 630-638.