Ultrasonographic patterns of ovarian activity during breastfeeding

Abstract

In this study, ultrasonography was used to detect follicular activity in lactating women, and these findings were related to the underlying hormonal profiles and to the mucus symptom. A number of different patterns of follicular development were seen before the women returned to normal fertile cycles during the period that was previously considered to be characterized by ovarian quiescence. Some of the transitory patterns of follicular activity were reflected in rising hormone levels and patterns of fertile mucus that were sometimes confusing for these lactating women who were using natural family planning.

PIP: The varieties of follicular development patterns seen on sonograms in lactating women before return to ovulatory cycles are described. 18 lactating women recorded mucus symptoms, basal body temperatures, breast and other feeds, and took timed urine samples for assay of estrogen, pregnanediol, and were scanned weekly. When follicular development or clinical symptoms suggested incipient ovulation, more frequent ultrasonography was done. There were several patterns of follicular development: multiple follicles, unruptured follicles, recurrent persistent follicles, and delayed ovulation. In many women early on, 3-20 small follicles developed in 1 of both ovaries, averaging 8 mm in diameter, with no release of estrogen or progesterone. 3 kinds of unruptured follicles were seen: luteinized unruptured follicles, atretic follicles and persistent follicles. Both luteinized and persistent unruptured follicles were accompanied by hormone release, and sometimes by long periods of wet cervical mucus. One women who breastfed intensively for 57 weeks had recurrent persistent follicles without any hormone or mucus symptoms. A scenario of apparently normal follicular development with an estrogen peak, but with ovulation delayed 2-3 days was also seen. Thus the previously held view that the ovary is quiescent during lactational amenorrhea is invalid. Use of the symptothermal method of natural family planning would be problematical urine prolonged lactation, given these findings.