Hypothesis: The investigators hypothesize that pulsatile FSH intravenous administration to women with obesity will correct the Reprometabolic Syndrome (RMS) luteal deficiency phenotype.

Specific Aim: To test the hypothesis that pulsatile IV administration of FSH will rescue the impaired folliculogenesis and relative hypogonadotropic hypogonadism, characteristic of obesity. The investigators will accomplish this by administering a cycle of pulsatile FSH to women with obesity and comparing their hormone output to a cycle using conventional, daily FSH injection at the identical daily dose. The primary outcome will be luteal phase progesterone excretion.

Design: Crossover interventional study. The investigators have selected this design to allow us to compare each woman to herself in consecutive cycles whenever possible.

Methods:

Patient population and protocol: The investigators plan to recruit women with obesity for a proof-of-concept study to demonstrate the potential of this treatment to improve fertility. Before such a treatment would be brought into clinical practice, a more comprehensive program of pre-conceptional care would be desirable to improve the metabolic health of women with obesity and minimize pregnancy complications such as preterm birth and pregnancy related hypertension.

However, that is not the goal of this preliminary study which only seeks to identify reproductive hormone impact.

Consent/Screening Process: A script for screening participants by telephone who inquire in response to advertisements will be used, which will include the required verbal consent language. Participants who are eligible for enrollment will be asked to come to the Clinical and Translational Research Center (CTRC) for an intake examination and qualifying laboratory tests. At this time, informed consent is obtained by the PI, the Professional Research Assistant, or an Institutional review Board (IRB) approved designee, according to the scripted process. The informed consent discussion is always held in a private room that is free of distractions and participants are allowed the opportunity to ask questions and have their questions answered to their satisfaction before signing the informed consent document. Once informed consent has been provided, procedures are performed as outlined in the procedures section.

The investigators will prepare the participants for either a cycle of pulsatile FSH or conventional, daily FSH injection at the identical daily dose of FSH for both conditions. Participants will be randomized to group A, pulsatile FSH and then conventional daily injected FSH, or group B, conventional FSH and then pulsatile FSH, by the study statistician. Participants will not be blinded to treatment. However, the PI and co-investigator, as well as the research assistant who will perform the assays, will not be expected to be involved in direct care of participants during treatment and will therefore be able to remain blinded to treatment assignment.

To control hormone delivery for both conditions (non-pulsatile FSH vs pulsatile FSH), all participants will receive a Gonadotropin Releasing Hormone (GnRH) antagonist during gonadotropin stimulation and up to the day of Human Chorionic Gonadotropin (HCG) trigger to abolish endogenous gonadotropin production. A baseline ultrasound will be performed within 2 days of the onset of menses to assure that no dominant follicles are present on ovarian ultrasound and E2 is <50 pg/ml prior to initiating stimulation, as per usual clinical practice. The remaining protocol will be administered in the second cycle, after a 1-month 'washout' period to avoid the possibility of carryover.

Inclusion Criteria:

• • BMI between 30 kg/m2 and 40 kg/m

  • Weight stability, i.e. no continued weight loss of >1lb per week for a minimum of 4 weeks prior to enrollment
  • Normal thyroid stimulating hormone (TSH) and prolactin
  • Anti-Mullerian Hormone (AMH) > 1 ng/ml or < 8 ng/mL
  • Willingness to postpone conception for the first study cycle
  • Involuntary inability to conceive for at least 6 months
  • No clinical diagnosis of polycystic ovarian syndrome (PCOS)
  • Documentation of ovulation with luteal progesterone >6 ng/ml or positive ovulation predictor home testing
  • Regular menstrual cycles 25-40 days in length
  • Male partner (or sperm donor) with adequate sperm (>14 million sperm per ml)
  • Hysterosalpingogram or saline infusion sonography demonstrating at least one patent Fallopian tube and a normal uterine cavity
  • Serum total and free testosterone within the 95% CIearance for women with obesity previously studied in our laboratory.
  • Acceptance of the indwelling catheter and willingness to take part in the study

Exclusion Criteria:

-

Females are only being recruited because this study looks at ovarian response