Monday, December 31, 2007

More questions about LAM

Thanks to Marianne Vanderveen-Kolkena for raising these questions. Perhaps you have shared her concerns...

Dear Marianne: Thank you for your interest in LAM. You raise relevant questions and I will do my best to answer:

1. Question: As far as I remember, I was taught that it is also necessary not to leave to many hours between feedings, so a night feeding ought to be part of the daily routine.In your explanation, I didn't find anything about not spacing feedings to wide apart. If you would breastfeed exclusively, but had a baby that sleeps through the night, then you could have an ovulation without bleeding first, right...? What is your opinion on this..?

Answer: The definition of Full Breastfeeding used in the LAM research was: feeding on demand, with no frequent intervals of >4 hours during the day or 6 hours during the night. The genesis of this definition would take a book of writing, but in the clinical trials of LAM, this is what we told women IF they asked. As to sleeping through the night, many women would consider 6 hour interval as sleeping through the night. Some women reported a midnight feed, and a 6 am feed, for example, and felt that they were sleeping through the night. Many women in the study occasionally had intervals of 8 hours at night, and this was not associated in any way with fertility in our study. Our recommendation is to feed physiologically, and on cue, and, if this is done, babies will wish to feed at least once during the night.

2. Question: Isn't is so, that estrogens have a higher chance of bringing the menstrual cycle back, if prolactin doesn't peak regularly enough?

Answer: This actually is a physiologically complex question. Here goes: Prolactin rise is associated with successful breastfeeding, and successful breastfeeding is associated with fertility suppression. There are some who assert that there are additional and alternative mechanisms that also are associated with the fertility suppression, mediated by the hypothalamus. Estrogen rise is associated with lack of regular rises in prolactin, however, estrogen rise is not necessarily a proxy for fertility return. In a fully lactating woman, a small estrogen rise is met with a paradoxical re-suppression of signs of fertility. For adequate ovulation to occur, there needs to be regular pulsatility of LH and FSH as well as declines in the rate of breastfeeding and its many hormonal effects. Estrogen, per se, does not bring back the cycle, but is a part of the cycle, and estrogen withdrawal causes the bleed. So, in a nutshell, if breastfeeding continues to be full, the chance of a small estrogen rise exists, but it is generally not adequate for ovulation. In general, in a fully lactating woman, a withdrawal bleed will occur prior to the first fertile cycle, and this phenomenon is the basis for LAM.

Thank you for your interest in LAM!!

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