Ultrasound Characterization of Ovarian Follicle Dynamics in Women With Amenorrhea

In the ovaries, eggs rest in fluid filled sacs called follicles. When follicles grow they
form small fluid-filled cysts that can be easily seen when we use ultrasound to view the
ovaries. In women with regular menstrual cycles, groups of 10 to 20 follicles grow and
regress at 2 or 3 different times during their cycle (usually over a 28- day period). Several
of these follicles grow to a stage where they begin to develop the potential to ovulate - but
in general only one follicle is chosen to ovulate. Thus, at any given time during the
menstrual cycle, numerous fluid-filled follicles can be visualized in a woman's ovaries at
various stages of development using transvaginal ultrasonography. In women with absent or
infrequent menstrual cycles, very little is known about the growth patterns of their
follicles and how factors such as metabolic hormones, might play a role in the failure to
ovulate. Being underweight or overweight increases your chances of having irregular or absent
menstrual cycles and that a history of abnormal reproductive function compounds a woman's
risk for chronic diseases such as infertility, diabetes, hypertension, atherosclerosis and
certain cancers. This is particularly the case for women with polycystic ovary syndrome
(PCOS) that have menstrual cycles that appear to worsen or improve depending on their body
weight and metabolic status. PCOS is an endocrine disorder that affects 6-12% of
reproductive-aged women within the general population. The hallmark features of PCOS are
menstrual irregularity, increased levels of androgens, and polycystic ovaries. The current
diagnostic criteria require 2 out of 3 of these features to be present for the diagnosis,
therefore a number of phenotypes of PCOS exist. However, the metabolic and reproductive
differences across the phenotypic spectrum of PCOS are not well understood. Women with PCOS
characteristically have polycystic ovaries, where up to 10 times more follicles are present
in the ovary at any given time. Further, the follicle-size populations and overall
distribution throughout the ovary varies in women - follicles may be situated around the
periphery of the ovary or may be distributed throughout the ovary. Presumably these small
follicles are arrested in development - but emerging data from the Lujan laboratory suggest
that this is not the case. It is assumed that ovulation does not occur and that follicles do
not grow in a normal wave pattern. In truth, no study has ever looked to see whether
follicles are actually growing, regressing or are arrested in women with irregular/absent
menstrual cycles. By comparing follicle wave dynamics, reproductive hormones and markers of
metabolism in women with regular and irregular menstrual cycles, the researchers plan to
identify what factors might explain why fertility potential and long-term health are
compromised in some women but not in others. Further, we will determine if any of these
metabolic factors are unique to PCOS representing specific metabolic risks or follicle growth
impairment. The ultimate goal of this research is to understand how body composition,
nutrition and metabolism regulate follicle development in women so we can better develop
lifestyle and drug therapies to help women preserve their fertility and long-term health.
Since obesity has recently become the leading cause of infertility in North America, these
studies are especially important.

To accomplish our objective, the investigators plan to recruit up to 40 women with regular
menstrual cycles and up to 40 women with irregular/absent menstrual cycles. Our goal is to
recruit an equal number of women in each group such that they are matched for age (18 - 35
years old) and body mass index (BMI; Normal weight = 18 - 24 kg/m2; Overweight = 25 - 29
kg/m2; Obese = 30kg/m2). Women will undergo serial ultrasonographic of their ovaries every
other day from ovulation to ovulation in women with regular menstrual cycles or for 5 weeks
in women with cycle irregularity. Blood samples will be collected at each visit. Ultrasound
scans of the ovaries will be assessed for the total number, size, and distribution of
follicles using ultrasound imaging techniques. Blood samples collected will be assayed to
determine serum concentrations of luteinizing hormone (LH), follicle stimulating hormone
(FSH), estradiol, progesterone, anti-müllerian hormone (AMH), and inhibin B. During day 3-5
in women with regular menstrual cycles or at a time where no dominant follicle or corpus
luteum is present, an early morning visit will be conducted to assess the following metabolic
parameters : (1) 75-gram oral glucose tolerance test to characterize glucose and insulin
dynamics at 0, 30, 60, 90, and 120 minutes post-glucose ingestion; (2) dual X-ray
absorptiometry (DXA) scan to quantify body fat and lean muscle distribution; (3) vitals and
anthropometry assessment to measure waist and hip circumference, height, weight, blood
pressure, and heart rate, and (4) fasting blood tests to detect serum concentrations of
androgens (i.e., total testosterone, androstenedione, free androgen index) and serum markers
of metabolic syndrome (i.e., lipids and hemoglobin A1C); (5) optional subcutaneous fat biopsy
to analyze fat cells, which represent a site of reproductive hormone synthesis.

Inclusion Criteria:

- Between 18 and 35 years

- BMI ≥ 18 kg/m2

- If ≥ 21 years old, must have had healthy pelvic exam w/in past 2 years

Either:

- Regular menstrual cycles (21-35 days);

- Irregular menstrual cycles (>36 days) with or without a previous diagnosis of PCOS
from a primary care provider

Exclusion Criteria:

- Current use of medication(s) known or suspected to interfere with reproductive
function (eg. oral contraceptives) or insulin sensitivity

- Pregnant or breastfeeding

- Not otherwise healthy