Nimodipine to Prevent LH Surge During Ovulation Induction: Blinded Placebo-controlled RCT

After enrollment, subjects will be randomized to Placebo Comparator or Active Comparator. All subjects will receive Clomid 100 mg for 5 days for the purpose of ovarian follicle recruitment. Intervention will be initiated once ovarian follicle maturation has been documented (≥1 ovarian follicle size of ≥ 17mm) and the absence of a premature LH surge has been confirmed - this will be classified as intervention day 0. Subjects will receive their assigned comparator (Placebo or Active) according the schedule below:

• Intervention Day 0 - noon / afternoon / bedtime (3 doses)
• Intervention Day 1 - morning / noon / afternoon / bedtime (4 doses)
• Intervention Day 2 - morning (1 dose) Serum hormone levels and ultrasound examination will occur on days 0,1 and 2 for all subjects.

Inclusion criteria

• Age 25-40 years at the time of enrollment
• Both ovaries intact by history and ultrasound assessment
• Early follicular phase (day 2-4) serum FSH level <20 mIU/mL
• Diagnosis of subfertility with a recommended treatment of COH and IUI
• Providing written informed consent in English

Exclusion criteria

• Body mass index (BMI) >38 kg/m2
• Early follicular phase (day 2-4) serum FSH level ≥20 mIU/mL
• History of overstimulated cycle defined as >3 mature follicles of ≥17 mm
• Abnormal uterine cavity and/or tubal disease (as evidenced by sonohysterogram or hysterosalpingogram)
• Diagnosis of infertility with a clear indication for in-vitro fertilization, such as bilateral tubal occlusion
• Severe male factor infertility: Total Motile Sperm Count < 2x106 post washing (sperm deemed inadequate for IUI preparation)
• Any ovarian or abdominal abnormality that may interfere with adequate TV ultrasound evaluation
• Absence of one or both ovaries
• Any contraindication to being pregnant or carrying a pregnancy to term
• Unexplained gynecological bleeding
• Any medical condition that would jeopardize the patient or the integrity of the data obtained including:
• Prior reaction or side effects from previous calcium channel blocker use
• Any medical condition that may interfere with the absorption, distribution, metabolism or excretion of nimodipine such as hepatic disease, hypertension, seizure, concurrent infection, depression, reflux (see #12 below).
• Mental health status resulting in cognitive or emotional impairment that would preclude study participation
• The concurrent use of any of the following drugs: [These medications have been shown to effect the availability of the medication or worsen hypotension symptoms]
• Antihypertensives (eg. ACE inhibitors, alpha-adrenergic blocking agents,methyldopa, beta-blockers, diuretics, PDE5 inhibitors, and other calcium antagonists)
• Antiepileptics (eg. phenobarbital, phenytoin, carbamazepine or valproic acid)
• Macrolide antibiotics (eg, erythromycin)
• Azole antimycotics (eg, ketoconazole)
• HIV protease inhibitors (eg, ritonavir)
• Antidepressants (eg, nefazodone and fluoxetine)
• Cimetidine
• Patient unable to communicate adequately with the investigators and to comply with the requirements of the study
• Unwillingness to give written informed consent