Prepregnancy Issues in Anorexia Nervosa
Amenorrhea is currently a diagnostic criterion for anorexia nervosa, although this will change with the next diagnostic scheme. Of women presenting with anorexia-like illness, between 68 and 89% report absence of menstruation for at least 3 months during the course of their illness.[10–13] An additional 6–8% of women may not experience prolonged amenorrhea, but report menstrual irregularity or oligomenorrhea.[11,13]
These disruptions in the normal menstrual cycle in many women with anorexia nervosa are probably manifestations of decreased systemic estrogen levels resulting from prolonged restriction of caloric intake and/or excessive exercise. Studies using pelvic ultrasonography in postpubertal women with current anorexia nervosa have demonstrated that, after significant weight loss, the uterus regresses back to its prepubertal length and the endometrial stripe seen on ultrasound can be either very thin or undetectable. The ovaries also regress to their prepubertal, immature size and some may not be visualized at all.
The high prevalence of menstrual disturbances led many to hypothesize that women with anorexia nervosa would be unlikely to conceive. However, outcome studies have consistently reported that fertility rates in women with a lifetime history of anorexia nervosa do not differ from women in the general population.[6,7,15,16] Two small studies have reported a high prevalence of lifetime eating disorder diagnoses (not exclusively anorexia nervosa) among women attending infertility clinics,[17,18] but other studies have found no differences in the rates of fertility treatment in women with anorexia nervosa compared with women in the general population.[6,7] Thus, it appears that despite the high prevalence of menstrual irregularities, women with anorexia nervosa are becoming pregnant.
Some women with anorexia nervosa may become pregnant during one of several intermittent phases (few months) of 'regular' ovulation and accompanying menstruation that may occur throughout the course of their illness. In others, pregnancy may occur in the absence of menstruation and can be explained similarly to rare cases of pregnancy in premenstrual adolescents (on menarche), nursing mothers and perimenopausal older women. When ovulation occurs for the first time after a period of amenorrhea and anovulation, it is possible for this first egg to become fertilized. The endometrial lining will then be maintained by the newly fertilized egg, and menstruation will not occur. Thus, a woman with anorexia nervosa may become pregnant without having experienced a resumption of menstruation.
Expert Rev of Obstet Gynecol. 2011;6(4):403-414. © 2011 Expert Reviews Ltd.
Cite this: Reproductive Issues in Anorexia Nervosa - Medscape - Aug 01, 2011.